Extremely, extremely helpful! Your explanation of cross correlate aligning multiple LPs before vector averaging them is eye opening! I learn so much from your videos, they shouldn't be free (:
I also agree...this should not be free...it is like real super knowledge which no youtuber will(I am sure that nobody has this kind of knowledge which OCA has) share....thats why I always say this is a real and the best info that this channel has...love and respect for you OCA
You made something I was dreading and thought was going to take a few days take a couple of hours with this method. You absolutely rock. I can't thank you enough.
Great tutorial. I asked for this multi-sub calibration in a previous video so thank you for delivering it OCA. One "tip" - start with the 'worst' sub as as starting point - that's the one with the least flat response at your MLP; and then fix it with the others. In my experience the OCA technique for time aligning ends up with a better bass control than MSO
Steep learning curve but you are making it accessible. New subscriber and ready to traverse the rabbit hole. I have three systems and I will start with the 2.2 system. Thank you and keep doing what you love.
First of all, my compliments on your knowledge of DSP, acoustics and overall audio knowledge. Your videos are very informative and well constructed. I recognize certain things in myself, as a fellow ocd.. Audio is great medicine for us! But now it can be a pitfall as well. But it’s my favourite hobby! Although I do measurements regularly, especially in FR, waterfall I experience problems in understanding some basic aspects in REW / measurements. For example, I still find it difficult to interpret phase, especially what to look for. Preferably as close to 0degree as possible, but the difference between good, acceptable and moderate? Same with impulse response, RT60 etc. Could you make a video explaining the basics especially what to look for with phase, rt60, clarity, impulse etc. What values are good, average or moderate.. I know there is a lot to read on the internet but nowhere can I find a clear video of what you want to look for in measurement results.
Good idea. I will work on this. I give bits and pieces of such information in parts of the videos but need to make one with an organized structure. In the meantime, REW's own manual (online) is quite a good place to start.
Thanks for the tutorial. Much appreciated! Question about the alignment tool in REW. What is the difference between the option 1. Align Phase SLOPES at cursor. and option 2. align Phase at cursor? While playing around with the software, I repeatedly found that option 2 tends to give a better summation where the resulting response (black line) had more positive summation than option one. What makes choosing option 1 the correct choice for your process and overall? Also, I'm using 4 subs and have 2 rows of seating (5 seats in total). I've used MSO which requires that each sub be measured at each seat, so in my case I have a total of 20 measurement for the subs. Can I use these measurements for your process, or do I need to measure each sub at each seat with multiple measurements positions per seat? MSO have given a very consistent seat to seat result, I'm wondering what issue you found with MSO when you used it?
Aligning phase slopes can be useful to spot where a polarity inversion may be required. If the phases with the slopes aligned are about 180 degrees apart, it points out to a polarity inversion requirement. Newer REW versions have an impulse alignment mode in the alignment tool which will automatically detect if a polarity change is required so you don't really need to bother with phase alignment. MSO is good with more than 2 subs and multiple seats.
Excellent video, and a good follow-up to your previous video on sub-alignment. I tried out your tips in practice from the last video, and ran some tests between a setup with one sub inverted (needing just a single ms of delay to get the best response. Having inverted one meant I also had very uniform bass between seats), and not inverting (requiring 15 ms of delay for best uniformity between seats and best response. REW predicted 12ms, but that gave horrible seat-to-seat consistency). The two setups didn't provide exactly the same response, but it got close, at least as far as FR was concerned. Looking at the predicted Impulse especially, inverting one seemed like the clear winner. However, I was experiencing what I can only describe as "directional bass" when playing loud and deep, where I'd suddenly feel like bass was only coming from one sub. And in particular I feel like with no polarity-switch I get much better pressurization, but that might just be psychoacoustics. Maintaining polarity significantly reduces this (I am in an L-shaped space, and one sub is near the opening to the L-part, which I feel might contribute), and looking at real-world impulse-responses and group-delays, even though the predicted response had the inverted polarity as a clear winner in these departments, in real-world testing they were much much closer, particularly in IR. Overall, I think my point is that even though these simulations and predictions can get you a long way towards a good response, you'll still need to measure and listen. However, without your last video on sub-correlation I'd never have thought to try it with a somewhat higher delay and no inversion.
You're right, listening is the ultimate test. In your case, the difference is mostly related to the L-shape of the room, one of the subs don't have rear wall reflections like the other one which boosts and dips its reponse differently compared to the other and when these frequencies are present in the track, you will hear directionality. You might consider lowering your crossover frequency to manage this to an extent.
@ocaudiophile you mention at 23:20 that you want the delay to small so that the bass won't be slow. Can you expand on that point? Are you talking about the peak of the impulse response coming later? Why is that a problem if you can just delay the other channels to match?
It's not going to slow the bass response when aligned with other speakers. Group delay slows the bass but wrongly I have referred to major Audyssey problems caused by longer delays between subs. When the subs system have long delays between them, automated systems like Audyssey cannot time align them with other speakers due to their very low total time delay limits.
Are you using a timing reference when taking your sub-only measurements? I don't see Phase Alignment as an option in the alignment tool. Maybe I have an older version.
I don't have hands on experience with open baffle systems but I don't see a reason for the method not to apply. Additional care should be taken to pick an aligned sum extending flat to higher frequencies I guess.
Thanks for posting all your helpful videos! In a previous video I think you said that RMS + phase avg superceded vector average, but here you are saying to use vector average. What is the difference between the two and when should each be used? Thanks again!
RMS + Phase is good for target curve level matching. To generate the real World response of two or more speakers acting together, you should always use vector average. When you measure both left and right speaker, this is only going to be identical to the vector average of individual responses of L & R.
Thank you so much for sharing your knowledge - especially your Audyssey A.R.T. I have never seen this talked about elsewhere and people spend a lot of money to get this level of DSP. Quick question: How would you align two subwoofers (fixed positions, phase dial, NO delay setting or anything else) if the receiver has only one distance setting and you don't own a miniDSP 2x4 (or other DSP)? a) Set both phases to 0, use alignment tool as you show in your videos and calculate the phase offset at the selected frequency b) Use RTA, turn the phase dial and see which gives the best result (I cannot get this to work for proper results) c) painstakingly measure sweeps with both subs whilst changing the phase a bit each measurement d) something else ? At the end set the cross correlated distance of both in the receiver of course (for speaker time alignment).
There's delay and trim settings in the ady file which control the relative distance and volume settings between the two subs. You can see and change how Audyssey set these up in the online json editor.
@@ocaudiophile How could the relative distance between both subs be adjusted by the key delayAdjustment if the sub outs are not independent (Denon x1500) meaning from Audysseys POV it should just be a single subwoofer? If it actually does that instead of delaying both subs relative to the speakers (which I don't understand how it would), I suppose I just punch in the number from REWs alignment tool.
@markusdittmer3402 I didn't know there are models with 2 subwoofer outputs which are not independent. That's basically just a y-splitter. If you're certain, then all you can do to adjust relative delays is to play around with sw phase settings. In the latest video, I've briefly shown how to calculate required phase shift for a certain delay at a certain frequency.
@@ocaudiophile Yeah sadly the receiver is like that. Calculating a required phase shift for a given frequency (which I meant by option A above) has the flaw that you will only 'optimize' for that frequency since for higher frequencies one required a higher phaseshift and then you have to remeasure the entire response anyways. So I will probably use RTA with sub call generator, average about 20 times and adjust the phase dial of one subwoofer in 5° steps until I find the best response (option B from above). Anyways, thank you for your insight and taking the time to reply.
Comparing their 0 deg phase responses at the MLP in Overlays with 1/1 octave band smoothing applied to both may give you a ball park figure idea of the overall phase shift one of the subs will require in the region 20Hz-xoHz. @dittmer3402
Thanks! I'm learning a lot from your videos. Question, for a 4 sub time alignment doing multiple mic positions, for a 3 east couch, and using cross correlation and vector average feature, what would be the ideal mic position separation to the left and to the right? And would it be beneficial to take a measurement in front of the MLP? Thanks again!
I think you can go all the way till the middle of each side seat with 4 subs, and one slightly forward measurement would not hurt either, we don't always use those seats leaned fully backwards. Keep the mic at ear height, sweeps loud and long and repeat more than once for the same mic position. Btw, free tool MSO (multiple sub optimizer) has a bit of a learning curve but is very good with 4 sub arrangements.
Thanks for the helpful video. Small technik question: To align the phase of one subwoofer with the front speaker, is it possible to use cross-correlation between the impulse response of the subwoofer and the front speaker, measured in the low frequency range (for example, 60-120Hz) instead fullrange measurements? Thank you beforehand.
Yes and it could give a more accurate result. But for best alignment between the fronts and sub, use REW's Alignment tool and "Align phase" at the crossover frequency.
First off, thank you for the instructional video. I've been a fan for a while. A question I have though is, after working thru the steps in this video would the next steps in a full manual calibration be your Audyssey A.R.T. video?
Hello OCA, could you please clarify this: At the time of aligning the speaker with the subs, I have two questions: 1. Do we align the (say) left front speaker with the vector average of the 2 subs or only SUB 1? This video seems to show that you are aligning the SUB1, but I think you meant to align with the vector average of the two subs. 2. Do we add/subtract time delay to the speaker or to the sub? This video seems to show that you are changing the delay of SUB1, but that means SUB 1 will get out of alignment with SUB2, essentially undoing what we did earlier (2 sub alignment), no? To keep the 2 subs in alignment with each other, I believe we should change the time delay of the front speaker.
I don't remember all the details in the video but you should always align the subs with each other first. Then generate a vector sum (vector average) of all the subs and treat this new measurement as a single subwoofer which needs to be aligned with your speakers. However, if you are using a stereo only system with 2 subs, you can use the new "directional bass" mode in latest Denon & Marantz receivers and in that mode you have to align each sub separately with each speaker but that's a quite different technique.
@@ocaudiophile Thank you! that makes sense. I have a Emotiva XMC-1, which has the capability of a stereo sub config where the two subs could have different filters, time alignments etc. But I feel they should first be time aligned with each other (using your procedure). After that I could time align the left front with the vector sum of the subs. But after that, I could make one set of filters with L sub + L front (not the vector sum). Does that make sense?
@@rajdude1 Yes, align them in Emotiva then measure again in REW all of that as one sub and the front left and right speakers. You can use vector average of left and right to time align that total sub using the same method in the video. But that probably also involves crossover frequency determination and applying crossover filters to the sub and speakers first. It's a bit tedious but apply different crossover frequencies around the spec bass roll off frequency of your speakers and measure each. Align each in alignment tool and compare aligned sums to pick the best XO frequency.
@@ocaudiophile thanks. I am trying to do all that but am very confused now. e.g. when I try to align the L main speaker with the vector sum of my 2 subs, do I change the delay on the mains speaker or both subs? I think I should change the delay on the L main, because in the next step, I gotta align the R main (and so forth). I cannot change the delay of the sub, because it will affect the alignment of the L main (which I did earlier). Am I correct?
@rajdude1, If above question is still relevant, I want to try to answer your question to the best of my knowledge. First, and this is important, you time align all speakers at the main listening position. Sound from all channels must arrive to the MLP at the same time, otherwise stereo/surround image will be shifted or you will hear echo effect. For stereo, your MLP generally shuld be at the same distance from each speaker, so the time delay for L and R should be the same. Once time delays for speakers are fixed, you then need to align combined sub to all speakers at once. For stereo it is a lot simpler, than for multi channel. You need to select XO frequency and try to find delay for the combined sub that integrates best at that frequency (less phase difference) with both L & R channels. But you should try to minimize sub delay. So you may need to try multiple XO frequencies, to choose the best combination (sub delay and frequency). What is combined sub delay? It could be a delay of sub1, for example. Delay of sub2 must be adjusted each time sub1 delay is changed, in order to preserve delay between subs, that was selected during sub alignment. Aligning sub is tricky, because it must be done for all speakers at once, and you need to select best XO frequency for each speaker. No single best delay for all speakers may be found. In this case, I think, you need to compromise, prioritise aligning subs with main LRC speakers, and then optimize XO frequencies for the rest of the speakers. Hope this is somewhat clear.
splendid showcase! I wonder whether or not live phase alignment similar to HEDD Audio's Lineariser is possible with use of 3rd party DSP? Best regards!!
I didn't know about HEDD systems but I checked. What it does seems to be very similar to what can be done with phase linearization tools in rePhase and FIR filters. I couldn't see a "live" adjustment element that's different.
You are a master at this. I have subwoofer group delay. Can this be cured with Dsp? I thought maybe allpass filters from rephase would do the trick but I don’t know how. And I already know you do haha.
You can usually remove group delay with time reversed (compensate mode in rephase) all pass filters. Watch the phase video. Phase Match Your Speakers with AllPass Filters ruclips.net/video/ChPu0u3nZxc/видео.html
Can this be done without a Mini DSP? The Marantz AV10 has directional bass and 4 x discreet subwoofer channels. Can this REW session analysis be entered directly into a processor and PEQ that support independent subwoofer channels?
You can adjust delay (distance) settings for each sub individually but manual Graphic Equalizers do not work on subwoofer channels in lesser Sound United models, I would assume AV10 will be no different. But in directional bass mode, Audyssey will create individual filters for each sub which can all be manipulated to use custom filters created in REW (see my Audyssey ART video). However, LFE channel will be run simultaneously on all 4 subs and there is no filter for the summation of all 4 subs anywhere.
I use remove IR delays frequently and am a big fan of it but didn't need that one yet. It's good if you wanna move speakers to a certain point in time. I'd assume, more useful to driver time alignments of DIY speakers.
Which version of REW are you using? I don't have the most recent, but I think it is a newer version than what you are using in the video. I don't have a cross correlation option. I remember having it in the previous version I had.
I don't remember really. I might be using a some custom version as I some times beta test new functions but I'll usually be using something very recent. I am currently using Beta 16.
The version you show in the video is what I'm familiar with, but I updated it. I updated 2 versions behind the most current. It's different than I'm used to. I'll probably just go back. Thanks.
First of all, my compliments on your knowledge of DSP, acoustics and overall audio knowledge. Your videos are very informative and well constructed. At minute 28:54 you say that to align my 2 subs with my fronts speakers I pick up the aligned sum. But later at 33min. in the video you don't seem to show how to do that. My questions are: Why do you use left speaker and sub A instead of aligned sum?do Ineed to vector average F an R responses and sumed them together befor to use the alignment toole with F+L sum and aligned subs sum?
Sorry for the confusing narrative there. You can replace "sub A" with the aligned sum of all your subs as if they are just one sub and align it to speaker A (ie your acoustic reference speaker)
Unrelated question: Have you used these products, and how would you compare them for stereo-DRC (among each other, and with REW)? Acourate, Audiolense, and DRC (by denis sbragion)
I tried DRC and Acourate, know about Audiolense a bit but never used it myself. All are great room/speaker correction software but REW also has very advanced tools now (that wasn't the case a year ago) and when used in combination with rePhase there's almost nothing it cannot do. However, it's all manual and has a learning curve. Acourate for example has macros which make it easier for beginners or people with limited time to spare to generate good results. The upcoming REW beta release will have API connection and after that I guess even that advantage will fade.
Thank you greatly for these videos. I found your channel last year and immediately subscribed. I've been watching and lowering. Around 16:04 you mention to set the range with cross over at 80hz if that's the person's choice. In one of your earlier videos you showed how to crossover the speakers using the final curve of the subwoofer. Which is the better option? As you showed in one of your videos, setting the end freq range to around 250 produces higher spl than going with 20000. Ive 2 subs. Is it necessary to volume align them? I think you mentioned it but I coukdnt get it well. My last question is once you get the target curve for the subs, should I volume align all speakers to it like you did in the Dolbt Atmos manual tuning complementary tutorial? Thank you again! You cant put a price to your videos. Super helpful and you still find time to answer questions too.
Where you crossover your sub with your speakers should ideally be based on your speakers' natural roll off frequency. This is usually given with -3dB or -6dB drop off frequencies in their specs. 80Hz is a THX standard believed to be the highest frequency where human ear can still not locate where the sound is coming from. This is important when a subwoofer is placed far from the speaker. In the video @ 16:04, 80Hz is given just as an example to explain how to accurately measure your subwoofer's volume level. If your crossover freq is 50Hz, it's meaningless to generate a pink noise covering from 20Hz to 100Hz and measure its volume. 20-50Hz is the wiser choice as the sub will only operate in that range. 2 subs will not be at equal distance and equal volume at the LP so before time aligning them between each other, it's useful to align their volumes to each other.But beyond that, playing with gain settings in the alignment tool will only gradually remove one sub from the equation. Target level matching is quite complex. I am still working on new methods to optimize it. In general, when you use REW's "calculate target level" tool in the EQ window with anything but unsmoothed response (all but the unsmoothed target level will be equal for the same response), you will see descent required volume adjustments between the speakers. Of course this will also depend on the target curve or room curve you use. There will be a video soon on target level matching (hopefully!).
Hi an other question. First I am only an amateur. I learned what I know about acoustic and DSP on the WEB an the book of Dr O'Toole since 2015. Before your video I thought that phase alignment between 2 subs and the Fronts satellites must to be done AFTER choosing an xo and then measuring 1) FL , FR, FL+FR with SUBS OFF and 2) Sug Left and sub Right ALONE at xo. Getting those 5 measurements we worked with alignment tool to find the smoothest response phase aligned at xo 80 for instance. Your video get rid of xo concerns. What happens when I choose an xo after phase aligned 2 sws with Fronts following like you teach us here? Does my question makes sense , hopefully?
You should aim to xo your speakers with the subs at or around their natural (spec) bass roll off frequency. For that xo to smoothly bond subs and speakers should also be in phase. This is not hard to achieve since you can also align relative volumes and strength of peaking filters. And sub timing is more important than all of these in my opinion because late bass arrival causes muddiness in the whole frequency band.
I expressed myself poorly. Usually I set the xo at 80Hz. If I had changed the xo say at 100Hz, I would have needed to redo all my measurements explained in my previous post. Yesterday I followed your method to phase align my 2 subs together and aligned the virtual one with my fronts and checked FR and FL responsee with 2 different xos. I was surprise to see that therewere quasi no frequency responses differences between xo 80 and xo 100. Is it a clue that I did well my homework or the contrary?@@ocaudiophile
I've watched the video twice and taken notes, but I'm running into a problem when trying to align 2 speakers , after I have the vector avg of 3 measurements I cross aligned, then take the 2 vector averaged traces in the impulse overlay, and put main window into impulse, the "clock adjustment" button is greyed out in the Actions menu. Driving me crazy. I can take just single measurements and see the Clock Adj button. What's going on? Wait, is it the "Offset t=0" I'm supposed to use?
Hey OCA, I ask myself if it is a plan of you at all to create a script which is doing this alignment automatically. I might be wrong but somewhere I thought you mentioned to think about that. I took a set of Audyssey measurements with each the right and left sub only but I am struggling to get those aligned in REW. I extracted the measurements from the .adys and renamed them (SW10-SW17, SW 20-SW27) in REW. Then I cross correlated them, took vector averages and tried aligning. When opening the alignment tool one sees a dotted line, guess this is what REW thinks could be the best outcome but after trying for hours I could not get there. What do you think? Thanks Sir.
That's the addition of both responses and represent the maximum limit of outcome for each frequency. It's not achievable altogether at every frequency.
@@ocaudiophilethanks,Sir. What is your take on a script doing that automatically (alignment)? Alternatively, is it possible to trick Evo to do that, is any description for a possible workaround available? Thanks for that great stuff.
Awesome video tutorial. What a coincidence as I was trying to get the best from my 2 subs. I am using your ART video with Audyssey. Can we use this with Audyssey measures?
Thanks for the tips. My HT room is a 9.2.4 within a rectangle (6,5m X 4,5m) and the Subs are opposite in corners (the front SW in the right corner and the back SW in the left corner). The front SW has 0º phase degrees and the back SW has 180º) and a strong null in the 40kh. In you tutorial should I take any additional attention in specific steps to set the SW as best as possible?
Hey OCA, great stuff, thanks. So aligning the first tiny peak is no longer the correct approach or is it still valid when using a DM device (6 M max distance to shortest located speaker)?
If you cannot set your hardware for the right distance then an earlier peak and if even that is not possible then aligning IR starts are still your only options. But they will be both compromised alignments.
If your sub was switched to 180 deg phase during measurement, you can gain about 2m distance @ 80Hz by switching it back to 0 deg but otherwise, you'll simply need 2m more of distance. "Assuming phase switch circuitry itself doesn't add additional system delays"
Hi. We have built a cinema at work(oil-rig), but I feel we doesn’t get the sound right. It’s a 5.4.4 system. Reciever is a Onkyo, so no Audyssey one possible… What approach would you suggest calibrating this. Minidsp on subs, wireless transfer to back subs. So lots of delay. By the way, one evo run nicely on my laptop for my private system 👍🏻🙂
The easy(easier) way is to measure each sub using acosutic timing reference at the MLP, generating their excess phase responses, applying a 24dB/oct low pass filter to them at 120Hz and then cross correlation align the results. It will give you how much delay each sub will need to reach MLP at the right time. The optimal way is to align all subs to each other at 50Hz with REW's "alignment tool" using "Impulse alignment". This will determine correct polarities and minimize delays. However, with 4 subs you will need to align 2 at a time and align the next with their "aligned sum" and so on. Also, the order you do this will change the results so you will need to check for 12 different combinations. Good luck with that ;)
Woha easy way is to buy new amp😂 But if I should follow one of your videos then? And this is a three row with 5 seats each row. Is there a point to spread measurements to each seat? I think this will degrade all seats and maybe focus measurements around middle row mid seat
Correct, focused measurement will be less uniform all around but better in the middle, the other will be not so good uniformly everywhere. Focus in the MLP and let the uniformity be handled by the number of subs.
So I’m a little confused I have Dirac live full version in avr and mini dsp hd 2x4 After aligning subs then aligning to my reference main where do I add delay ? Do I rerun Dirac and set that delay in the distance of sub in avr ? Or do I let Dirac pick the new distance /delay ?
I will let the final say happen by OCA, but from what I understand this procedure is all about doing it manually using REW. I have Dirac live too, but Dirac is OUT of the picture if you wanna tweak manually, meaning we no longer use Dirac. Here is the procedure in a nutshell - You gotta first time align all the subs, then make a "phantom sub" in REW. Then you time align the speakers one by one (by adding delay to them in the AVR) to that single, phantom sub. AFTER all that you can equalize the speakers by adding filters.
@@rajdude1 since you can’t adjust distance/delay in avr as it is locked by Dirac do I have to factory reset the avr every time and rerun Dirac ? How else can it be done?
@@andyv9365 no no. Like I said earlier, (if you want to do this manually, and follow this video) you have to stop using Dirac. You have to use one of the other modes of EQ in the AVR. For example, my AVR, an Emotiva XMC-1 has these presets - Dirac, preset 1 and preset 2. So I first put my AVR into preset 1, and then work on this procedure.
I have now viewed just about all of your videos in just the past week. Fantastic Job and thank you for making them! I have been doing things (the older way) I guess you could say with REW. Any suggestions where to start first? I want to basically do everything over. 7.1.6 system. Three subwoofers as of now. Hopefully will be able to cut that down to two subs when the new one arrives. Should I start with all of the speakers first? Then do the subs? Other way around? Not sure what is the best way to approach this? As of now I recently downloaded the REW equalizer filters and REW Atmos sweeps that you provided the links for. Have a Denon receiver with xt32 and editor app, and minidsp 2x4 hd. Let me know your thoughts on this if you get a chance please. Thank you!
A lot of the videos are for stereo listening and requires a PC as a music player because the filters created require lots of taps only PCs can handle. When all filtering needs to be done in the multichannel receiver, you are bound to use Audyssey (which has only 1024 filter taps) and you can manipulate it by using the Editor app but you cannot do any phase correction for example. I use an integrated stereo amp with Home Theatre bypass property connected to front pre outs of my AVR and also connected by XLR inputs to my PC and Dac. This way, I can add two more channels to my Atmos system and also use the front speakers as a very capable hifi stereo system with any kind of filters I want simultaneously. Now for your case, connect all subs to MiniDSP and use that as a single sub in the AVR with Audyssey. You can align the subs for relative delays in the MiniDSP using MSO or the method explained here but make sure you don't induce long delays to any sub. The AVR has a 20ms maximum delay limit and beyond that, it cannot synch your sub system to your speakers. You also do not need to use any EQ for your subs in MiniDSP unless you have peaks above 20dB. Then run a careful Audyssey calibration from the app and feed the calibration file to Audyssey One (see my latest video). It will do everything for you in the best possible way.
Align subs in REW with minidsp (not a problem / no low shelf filter or high pass filters in minidsp ), no eq at unless peaks above 20dB (understood). What will the Audyssey One do with the subs below 20hz? I am pretty darn flat to 10hz. Thank you for all of your help! Greatly appreciated!@@ocaudiophile
what about the tactical response I have now? Using a low shelf filter at about 47hz I believe 0.7 Q with a 6dB rise. I also just tried Audyssey One. I just uploaded a file I had from the editor app. I followed your instructions and I belive i did it correctly but when i watched your video tutorial on Audyssey One the Dr Toole target curve does not look the same? Mine is basically flat. Starts at 24k hz at 75 SPL and ends at about 3 hz which it rises to about 82.1 spl? What did I do? Doe @@ocaudiophile
I have two subs (different kinds) connected to a NX3000D in front next to my speakers and I'm seated only 2,5m away. But for some reason I can't seem to get a good flat response. And when I get something that comes close to the house curve, it sounds very flat. I'm not sure what I'm doing wrong....
Go for the "Aligned Sum" that yields the highest peaks. Don't forget to try with one sub inverted. You can always create a flat response with filters later.
Thank you for making these videos. Wonder if you can help me with some issues. Cinema room. Three seat rows. Four subwoofers. I aligned them but when trying to timealign to center I get a 25ms delay even when distanse is at max 9meters. 25 ms positive in relation to center. Two subs in back corner have wireless signal to minidsp. What can I do to get subs and center aligned? And last question: can I trust impulsepeaks regarding to phase? It looks like right speaker have peak in opposite direction to the rest.. thanks 🙂
Even within same brands of speakers impulse peaks may sometimes reverse due to mic position and reflections though rare. Best way to check is in Overlays/phase graphs with all speakers shown. Click "invert polarity" repeatedly for that speaker and check which one has a better phase fit to the rest of the speakers. You can 1/1 smooth all responses to see more easily. Your subwoofer alignment problem is tough to solve with Denon/Marant units especially when even the actual distances we are talking about are around 9m and wireless connections on top of that. You should maybe go with the "directional bass" mode. At least subs will be closer to where the signals are coming from. You can switch to that mode by using the app even if your AVR is an older model. Let me know what you decide to do.
Directional bass is not available in my Onkyo.. Fysical distance is about 5m to front and 2m to back subs. Any recievers with larger distance adjustments?
You might have it through the app: audiosciencereview.com/forum/index.php?threads/audyssey-manual-calibration-master-stroke.46120/post-1658127 @@oddkjetil1030
Sir,sorry for disturbing you again... May you pls clarify:- 1. While measuring with your 1M sweeps,what should ideally be the master volume in the receiver set to....(Should it be set to your usual listening db level in my case it is I usually listen my content at -10db) 2. One reason I am asking you is this (while I corrected my laptop sound setting for my UMIk 1): when I was measuring with your 1M sweeps it at even -10db level it reports of clipping and says reducing the sweep level,processor volume setting.... Requesting you for help sir Thanks and respect for you
Thank you, that probably why I had a 10db peak in one seat, my AVR had distance set by audyssey one sub was 13feet the other 9 feet , my subs are the same distance from the MLP , no delay is really needed when I align them
If we are time aligning all speakers and the combined sub response to the center channel which is also my acoustic timing reference, then what is the benefit of aligning the speakers and subs as explained in this video? Thanks
@@ocaudiophile I am trying to understand the difference. In the end don't both approaches result in subs and speakers aligned to each other? I am referring to the process you explained in the supreme audyssey calibration video
This video explains various ways to optimize time alignment. Method is not different to the one in Supreme Audyssey video. At the end of the day, there's only one correct time alignment for a given set of subs and speakers. I was going to include a section on how to deal with Audyssey 6m speaker distance limit as this is a very common complaint but that will be covered in a future Audyssey video.@@Rayman-expertsoundpro
PLEASE HELP. I am trying to wrap my head around this concept. I have two subs in what I call a stereo sub config, where the 2 subs are kept right next to the front main speakers. Room is multi purpose, used for both movies and music. It seems to me I have two options - 1. Align my two subs first. Then align the phantom sub with the main speakers (that is what you seem to be saying). 2. Align the left sub to the L main speaker and right sub to the R main speaker, which this guy seems to be describing ruclips.net/video/yMussZ1C-dE/видео.htmlsi=539ppQzrJftwEZUT BUT which option is the correct option? Sorry, I am totally confused here 😞
@@ocaudiophile thank you OCA! I'll follow this video then. 👍 One more question please...Once I have the phantom sub in REW, should I align it to both L and R mains one by one? Or is there some other method available? BTW, I have an Emotiva XMC-1, two Rythmik 15" servo subs, Magnepan 3.6r and Bryston monoblocks (also have Magnepan center and surrounds)
You need to equalize left and right speakers to the same target curve and align their impulse peaks. Then you can use the vector average of these 2 to align with the combined sub response for a suitable crossover frequency.
A 'game changer' video is coming very very soon! In the mean time, run a descent 8-microphone position Audyssey calibration with the app and save the calibration file 'as is' in a safe place ;)
Audyssey methods work only with Audyssey and some older Onkyo's might also use (I think). There's also a link in AUdyssey ART video description for a script to decode Anthem arc measurements to REW if it helps.
![Gunna - HIM ALL ALONG [Official Visualizer]](http://i.ytimg.com/vi/HiCxoDeo0hc/mqdefault.jpg)
Extremely, extremely helpful! Your explanation of cross correlate aligning multiple LPs before vector averaging them is eye opening! I learn so much from your videos, they shouldn't be free (:
Great to hear!
I also agree...this should not be free...it is like real super knowledge which no youtuber will(I am sure that nobody has this kind of knowledge which OCA has) share....thats why I always say this is a real and the best info that this channel has...love and respect for you OCA
Is there an OCA Patreon account?
You made something I was dreading and thought was going to take a few days take a couple of hours with this method. You absolutely rock. I can't thank you enough.
Glad I could help!
Thank you for the great, extremely helpful tutorial on multiple sub time and phase alignment.
Your welcome...
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T H A N K Y O U F O R W A T C H I N G !
P L E A S E L I K E A N D S U B S C R I B E !
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Great tutorial. I asked for this multi-sub calibration in a previous video so thank you for delivering it OCA.
One "tip" - start with the 'worst' sub as as starting point - that's the one with the least flat response at your MLP; and then fix it with the others.
In my experience the OCA technique for time aligning ends up with a better bass control than MSO
For two subs, you really don't need MSO unless you can find some use for allpass filters.
Another great video OCA, thanks for sharing this!
Cheers m8!
Any time, keep up the great work OCA.@@ocaudiophile
My head hurts 😫
You are a wizard with REW. I hear you saying many times it’s logical 😮not for mere humans
Steep learning curve but you are making it accessible. New subscriber and ready to traverse the rabbit hole. I have three systems and I will start with the 2.2 system. Thank you and keep doing what you love.
Your welcome.
First of all, my compliments on your knowledge of DSP, acoustics and overall audio knowledge. Your videos are very informative and well constructed. I recognize certain things in myself, as a fellow ocd.. Audio is great medicine for us! But now it can be a pitfall as well. But it’s my favourite hobby!
Although I do measurements regularly, especially in FR, waterfall I experience problems in understanding some basic aspects in REW / measurements.
For example, I still find it difficult to interpret phase, especially what to look for. Preferably as close to 0degree as possible, but the difference between good, acceptable and moderate? Same with impulse response, RT60 etc.
Could you make a video explaining the basics especially what to look for with phase, rt60, clarity, impulse etc. What values are good, average or moderate..
I know there is a lot to read on the internet but nowhere can I find a clear video of what you want to look for in measurement results.
Good idea. I will work on this. I give bits and pieces of such information in parts of the videos but need to make one with an organized structure. In the meantime, REW's own manual (online) is quite a good place to start.
Its like fab...OCA always rocks
Thanks, least I can do for such wonderful followers.
😊
Thanks for the tutorial. Much appreciated! Question about the alignment tool in REW. What is the difference between the option 1. Align Phase SLOPES at cursor. and option 2. align Phase at cursor? While playing around with the software, I repeatedly found that option 2 tends to give a better summation where the resulting response (black line) had more positive summation than option one. What makes choosing option 1 the correct choice for your process and overall? Also, I'm using 4 subs and have 2 rows of seating (5 seats in total). I've used MSO which requires that each sub be measured at each seat, so in my case I have a total of 20 measurement for the subs. Can I use these measurements for your process, or do I need to measure each sub at each seat with multiple measurements positions per seat? MSO have given a very consistent seat to seat result, I'm wondering what issue you found with MSO when you used it?
Aligning phase slopes can be useful to spot where a polarity inversion may be required. If the phases with the slopes aligned are about 180 degrees apart, it points out to a polarity inversion requirement. Newer REW versions have an impulse alignment mode in the alignment tool which will automatically detect if a polarity change is required so you don't really need to bother with phase alignment.
MSO is good with more than 2 subs and multiple seats.
Eagerly waiting sir😊
Cheers!
Do you do remote calibrations ?
Only if you run into problems trying yourself ;)
Excellent video, and a good follow-up to your previous video on sub-alignment.
I tried out your tips in practice from the last video, and ran some tests between a setup with one sub inverted (needing just a single ms of delay to get the best response. Having inverted one meant I also had very uniform bass between seats), and not inverting (requiring 15 ms of delay for best uniformity between seats and best response. REW predicted 12ms, but that gave horrible seat-to-seat consistency). The two setups didn't provide exactly the same response, but it got close, at least as far as FR was concerned.
Looking at the predicted Impulse especially, inverting one seemed like the clear winner. However, I was experiencing what I can only describe as "directional bass" when playing loud and deep, where I'd suddenly feel like bass was only coming from one sub. And in particular I feel like with no polarity-switch I get much better pressurization, but that might just be psychoacoustics.
Maintaining polarity significantly reduces this (I am in an L-shaped space, and one sub is near the opening to the L-part, which I feel might contribute), and looking at real-world impulse-responses and group-delays, even though the predicted response had the inverted polarity as a clear winner in these departments, in real-world testing they were much much closer, particularly in IR.
Overall, I think my point is that even though these simulations and predictions can get you a long way towards a good response, you'll still need to measure and listen.
However, without your last video on sub-correlation I'd never have thought to try it with a somewhat higher delay and no inversion.
You're right, listening is the ultimate test. In your case, the difference is mostly related to the L-shape of the room, one of the subs don't have rear wall reflections like the other one which boosts and dips its reponse differently compared to the other and when these frequencies are present in the track, you will hear directionality. You might consider lowering your crossover frequency to manage this to an extent.
@ocaudiophile you mention at 23:20 that you want the delay to small so that the bass won't be slow. Can you expand on that point? Are you talking about the peak of the impulse response coming later? Why is that a problem if you can just delay the other channels to match?
It's not going to slow the bass response when aligned with other speakers. Group delay slows the bass but wrongly I have referred to major Audyssey problems caused by longer delays between subs. When the subs system have long delays between them, automated systems like Audyssey cannot time align them with other speakers due to their very low total time delay limits.
Are you using a timing reference when taking your sub-only measurements? I don't see Phase Alignment as an option in the alignment tool. Maybe I have an older version.
Yes for phase and time alignment acoustic or loopback timing ref is a must. Search for REW Beta download page in AVNirvana
Awesome
Thanks!
Wunderbar
danke dır!
Thank you for sharing your expertise! Do your techniques require modification for open-baffle mains?
I don't have hands on experience with open baffle systems but I don't see a reason for the method not to apply. Additional care should be taken to pick an aligned sum extending flat to higher frequencies I guess.
Thanks!
Thank you!
Thanks for posting all your helpful videos! In a previous video I think you said that RMS + phase avg superceded vector average, but here you are saying to use vector average. What is the difference between the two and when should each be used?
Thanks again!
RMS + Phase is good for target curve level matching. To generate the real World response of two or more speakers acting together, you should always use vector average. When you measure both left and right speaker, this is only going to be identical to the vector average of individual responses of L & R.
Thank you so much for sharing your knowledge - especially your Audyssey A.R.T. I have never seen this talked about elsewhere and people spend a lot of money to get this level of DSP.
Quick question: How would you align two subwoofers (fixed positions, phase dial, NO delay setting or anything else) if the receiver has only one distance setting and you don't own a miniDSP 2x4 (or other DSP)? a) Set both phases to 0, use alignment tool as you show in your videos and calculate the phase offset at the selected frequency b) Use RTA, turn the phase dial and see which gives the best result (I cannot get this to work for proper results) c) painstakingly measure sweeps with both subs whilst changing the phase a bit each measurement d) something else ?
At the end set the cross correlated distance of both in the receiver of course (for speaker time alignment).
There's delay and trim settings in the ady file which control the relative distance and volume settings between the two subs. You can see and change how Audyssey set these up in the online json editor.
@@ocaudiophile How could the relative distance between both subs be adjusted by the key delayAdjustment if the sub outs are not independent (Denon x1500) meaning from Audysseys POV it should just be a single subwoofer? If it actually does that instead of delaying both subs relative to the speakers (which I don't understand how it would), I suppose I just punch in the number from REWs alignment tool.
@markusdittmer3402 I didn't know there are models with 2 subwoofer outputs which are not independent. That's basically just a y-splitter. If you're certain, then all you can do to adjust relative delays is to play around with sw phase settings. In the latest video, I've briefly shown how to calculate required phase shift for a certain delay at a certain frequency.
@@ocaudiophile Yeah sadly the receiver is like that. Calculating a required phase shift for a given frequency (which I meant by option A above) has the flaw that you will only 'optimize' for that frequency since for higher frequencies one required a higher phaseshift and then you have to remeasure the entire response anyways. So I will probably use RTA with sub call generator, average about 20 times and adjust the phase dial of one subwoofer in 5° steps until I find the best response (option B from above).
Anyways, thank you for your insight and taking the time to reply.
Comparing their 0 deg phase responses at the MLP in Overlays with 1/1 octave band smoothing applied to both may give you a ball park figure idea of the overall phase shift one of the subs will require in the region 20Hz-xoHz. @dittmer3402
Thanks! I'm learning a lot from your videos. Question, for a 4 sub time alignment doing multiple mic positions, for a 3 east couch, and using cross correlation and vector average feature, what would be the ideal mic position separation to the left and to the right? And would it be beneficial to take a measurement in front of the MLP? Thanks again!
I think you can go all the way till the middle of each side seat with 4 subs, and one slightly forward measurement would not hurt either, we don't always use those seats leaned fully backwards. Keep the mic at ear height, sweeps loud and long and repeat more than once for the same mic position. Btw, free tool MSO (multiple sub optimizer) has a bit of a learning curve but is very good with 4 sub arrangements.
That's awesome! Thank you for your recommendation and keep up the good work.
Thanks for the helpful video. Small technik question: To align the phase of one subwoofer with the front speaker, is it possible to use cross-correlation between the impulse response of the subwoofer and the front speaker, measured in the low frequency range (for example, 60-120Hz) instead fullrange measurements? Thank you beforehand.
Yes and it could give a more accurate result. But for best alignment between the fronts and sub, use REW's Alignment tool and "Align phase" at the crossover frequency.
First off, thank you for the instructional video. I've been a fan for a while. A question I have though is, after working thru the steps in this video would the next steps in a full manual calibration be your Audyssey A.R.T. video?
Yes, it has the better scripts and explains how to embed manual REW measurements into Audyssey.
Hello OCA, could you please clarify this: At the time of aligning the speaker with the subs, I have two questions:
1. Do we align the (say) left front speaker with the vector average of the 2 subs or only SUB 1?
This video seems to show that you are aligning the SUB1, but I think you meant to align with the vector average of the two subs.
2. Do we add/subtract time delay to the speaker or to the sub?
This video seems to show that you are changing the delay of SUB1, but that means SUB 1 will get out of alignment with SUB2, essentially undoing what we did earlier (2 sub alignment), no? To keep the 2 subs in alignment with each other, I believe we should change the time delay of the front speaker.
I don't remember all the details in the video but you should always align the subs with each other first. Then generate a vector sum (vector average) of all the subs and treat this new measurement as a single subwoofer which needs to be aligned with your speakers. However, if you are using a stereo only system with 2 subs, you can use the new "directional bass" mode in latest Denon & Marantz receivers and in that mode you have to align each sub separately with each speaker but that's a quite different technique.
@@ocaudiophile Thank you! that makes sense.
I have a Emotiva XMC-1, which has the capability of a stereo sub config where the two subs could have different filters, time alignments etc. But I feel they should first be time aligned with each other (using your procedure). After that I could time align the left front with the vector sum of the subs. But after that, I could make one set of filters with L sub + L front (not the vector sum). Does that make sense?
@@rajdude1 Yes, align them in Emotiva then measure again in REW all of that as one sub and the front left and right speakers. You can use vector average of left and right to time align that total sub using the same method in the video. But that probably also involves crossover frequency determination and applying crossover filters to the sub and speakers first. It's a bit tedious but apply different crossover frequencies around the spec bass roll off frequency of your speakers and measure each. Align each in alignment tool and compare aligned sums to pick the best XO frequency.
@@ocaudiophile thanks. I am trying to do all that but am very confused now. e.g. when I try to align the L main speaker with the vector sum of my 2 subs, do I change the delay on the mains speaker or both subs? I think I should change the delay on the L main, because in the next step, I gotta align the R main (and so forth). I cannot change the delay of the sub, because it will affect the alignment of the L main (which I did earlier). Am I correct?
@rajdude1,
If above question is still relevant, I want to try to answer your question to the best of my knowledge.
First, and this is important, you time align all speakers at the main listening position. Sound from all channels must arrive to the MLP at the same time, otherwise stereo/surround image will be shifted or you will hear echo effect. For stereo, your MLP generally shuld be at the same distance from each speaker, so the time delay for L and R should be the same.
Once time delays for speakers are fixed, you then need to align combined sub to all speakers at once. For stereo it is a lot simpler, than for multi channel. You need to select XO frequency and try to find delay for the combined sub that integrates best at that frequency (less phase difference) with both L & R channels. But you should try to minimize sub delay. So you may need to try multiple XO frequencies, to choose the best combination (sub delay and frequency).
What is combined sub delay?
It could be a delay of sub1, for example. Delay of sub2 must be adjusted each time sub1 delay is changed, in order to preserve delay between subs, that was selected during sub alignment.
Aligning sub is tricky, because it must be done for all speakers at once, and you need to select best XO frequency for each speaker. No single best delay for all speakers may be found. In this case, I think, you need to compromise, prioritise aligning subs with main LRC speakers, and then optimize XO frequencies for the rest of the speakers.
Hope this is somewhat clear.
splendid showcase!
I wonder whether or not live phase alignment similar to HEDD Audio's Lineariser is possible with use of 3rd party DSP?
Best regards!!
I didn't know about HEDD systems but I checked. What it does seems to be very similar to what can be done with phase linearization tools in rePhase and FIR filters. I couldn't see a "live" adjustment element that's different.
You are a master at this. I have subwoofer group delay. Can this be cured with Dsp? I thought maybe allpass filters from rephase would do the trick but I don’t know how. And I already know you do haha.
You can usually remove group delay with time reversed (compensate mode in rephase) all pass filters. Watch the phase video.
Phase Match Your Speakers with AllPass Filters
ruclips.net/video/ChPu0u3nZxc/видео.html
Can this be done without a Mini DSP?
The Marantz AV10 has directional bass and 4 x discreet subwoofer channels. Can this REW session analysis be entered directly into a processor and PEQ that support independent subwoofer channels?
You can adjust delay (distance) settings for each sub individually but manual Graphic Equalizers do not work on subwoofer channels in lesser Sound United models, I would assume AV10 will be no different. But in directional bass mode, Audyssey will create individual filters for each sub which can all be manipulated to use custom filters created in REW (see my Audyssey ART video). However, LFE channel will be run simultaneously on all 4 subs and there is no filter for the summation of all 4 subs anywhere.
Hi, Have you tried the "Allign IRs at cursor" function in allignment tool? Any thoughts on that?
I use remove IR delays frequently and am a big fan of it but didn't need that one yet. It's good if you wanna move speakers to a certain point in time. I'd assume, more useful to driver time alignments of DIY speakers.
Which version of REW are you using? I don't have the most recent, but I think it is a newer version than what you are using in the video. I don't have a cross correlation option. I remember having it in the previous version I had.
I don't remember really. I might be using a some custom version as I some times beta test new functions but I'll usually be using something very recent. I am currently using Beta 16.
The version you show in the video is what I'm familiar with, but I updated it. I updated 2 versions behind the most current. It's different than I'm used to. I'll probably just go back. Thanks.
First of all, my compliments on your knowledge of DSP, acoustics and overall audio knowledge. Your videos are very informative and well constructed. At minute 28:54 you say that to align my 2 subs with my fronts speakers I pick up the aligned sum. But later at 33min. in the video you don't seem to show how to do that. My questions are: Why do you use left speaker and sub A instead of aligned sum?do Ineed to vector average F an R responses and sumed them together befor to use the alignment toole with F+L sum and aligned subs sum?
Sorry for the confusing narrative there. You can replace "sub A" with the aligned sum of all your subs as if they are just one sub and align it to speaker A (ie your acoustic reference speaker)
AH! merci!!@@ocaudiophile
Unrelated question: Have you used these products, and how would you compare them for stereo-DRC (among each other, and with REW)?
Acourate, Audiolense, and DRC (by denis sbragion)
I tried DRC and Acourate, know about Audiolense a bit but never used it myself. All are great room/speaker correction software but REW also has very advanced tools now (that wasn't the case a year ago) and when used in combination with rePhase there's almost nothing it cannot do. However, it's all manual and has a learning curve. Acourate for example has macros which make it easier for beginners or people with limited time to spare to generate good results. The upcoming REW beta release will have API connection and after that I guess even that advantage will fade.
Thank you greatly for these videos. I found your channel last year and immediately subscribed. I've been watching and lowering.
Around 16:04 you mention to set the range with cross over at 80hz if that's the person's choice. In one of your earlier videos you showed how to crossover the speakers using the final curve of the subwoofer. Which is the better option?
As you showed in one of your videos, setting the end freq range to around 250 produces higher spl than going with 20000.
Ive 2 subs. Is it necessary to volume align them? I think you mentioned it but I coukdnt get it well.
My last question is once you get the target curve for the subs, should I volume align all speakers to it like you did in the Dolbt Atmos manual tuning complementary tutorial?
Thank you again! You cant put a price to your videos. Super helpful and you still find time to answer questions too.
Where you crossover your sub with your speakers should ideally be based on your speakers' natural roll off frequency. This is usually given with -3dB or -6dB drop off frequencies in their specs. 80Hz is a THX standard believed to be the highest frequency where human ear can still not locate where the sound is coming from. This is important when a subwoofer is placed far from the speaker. In the video @ 16:04, 80Hz is given just as an example to explain how to accurately measure your subwoofer's volume level. If your crossover freq is 50Hz, it's meaningless to generate a pink noise covering from 20Hz to 100Hz and measure its volume. 20-50Hz is the wiser choice as the sub will only operate in that range.
2 subs will not be at equal distance and equal volume at the LP so before time aligning them between each other, it's useful to align their volumes to each other.But beyond that, playing with gain settings in the alignment tool will only gradually remove one sub from the equation.
Target level matching is quite complex. I am still working on new methods to optimize it. In general, when you use REW's "calculate target level" tool in the EQ window with anything but unsmoothed response (all but the unsmoothed target level will be equal for the same response), you will see descent required volume adjustments between the speakers. Of course this will also depend on the target curve or room curve you use. There will be a video soon on target level matching (hopefully!).
Thank you!@@ocaudiophile
Hi an other question. First I am only an amateur. I learned what I know about acoustic and DSP on the WEB an the book of Dr O'Toole since 2015. Before your video I thought that phase alignment between 2 subs and the Fronts satellites must to be done AFTER choosing an xo and then measuring 1) FL , FR, FL+FR with SUBS OFF and 2) Sug Left and sub Right ALONE at xo. Getting those 5 measurements we worked with alignment tool to find the smoothest response phase aligned at xo 80 for instance. Your video get rid of xo concerns. What happens when I choose an xo after phase aligned 2 sws with Fronts following like you teach us here? Does my question makes sense , hopefully?
You should aim to xo your speakers with the subs at or around their natural (spec) bass roll off frequency. For that xo to smoothly bond subs and speakers should also be in phase. This is not hard to achieve since you can also align relative volumes and strength of peaking filters. And sub timing is more important than all of these in my opinion because late bass arrival causes muddiness in the whole frequency band.
I expressed myself poorly. Usually I set the xo at 80Hz. If I had changed the xo say at 100Hz, I would have needed to redo all my measurements explained in my previous post. Yesterday I followed your method to phase align my 2 subs together and aligned the virtual one with my fronts and checked FR and FL responsee with 2 different xos. I was surprise to see that therewere quasi no frequency responses differences between xo 80 and xo 100. Is it a clue that I did well my homework or the contrary?@@ocaudiophile
I've watched the video twice and taken notes, but I'm running into a problem when trying to align 2 speakers , after I have the vector avg of 3 measurements I cross aligned, then take the 2 vector averaged traces in the impulse overlay, and put main window into impulse, the "clock adjustment" button is greyed out in the Actions menu.
Driving me crazy.
I can take just single measurements and see the Clock Adj button.
What's going on?
Wait, is it the "Offset t=0" I'm supposed to use?
Try "Remove IR delays" first and see where the impulse peaks move.
Fantastic and +++
Many thanks!!
Hey OCA, I ask myself if it is a plan of you at all to create a script which is doing this alignment automatically. I might be wrong but somewhere I thought you mentioned to think about that. I took a set of Audyssey measurements with each the right and left sub only but I am struggling to get those aligned in REW. I extracted the measurements from the .adys and renamed them (SW10-SW17, SW 20-SW27) in REW. Then I cross correlated them, took vector averages and tried aligning. When opening the alignment tool one sees a dotted line, guess this is what REW thinks could be the best outcome but after trying for hours I could not get there. What do you think? Thanks Sir.
That's the addition of both responses and represent the maximum limit of outcome for each frequency. It's not achievable altogether at every frequency.
@@ocaudiophilethanks,Sir. What is your take on a script doing that automatically (alignment)? Alternatively, is it possible to trick Evo to do that, is any description for a possible workaround available? Thanks for that great stuff.
Good idea and noted as the next video idea
Awesome video tutorial. What a coincidence as I was trying to get the best from my 2 subs. I am using your ART video with Audyssey. Can we use this with Audyssey measures?
Yes, you have to enter the distance between the two subs in MultEQ Editor under SW2 "delay" setting in meters.
Thanks for the tips. My HT room is a 9.2.4 within a rectangle (6,5m X 4,5m) and the Subs are opposite in corners (the front SW in the right corner and the back SW in the left corner). The front SW has 0º phase degrees and the back SW has 180º) and a strong null in the 40kh. In you tutorial should I take any additional attention in specific steps to set the SW as best as possible?
I'd measure both subs separately at the LP and play with the Alignment tool to see if I can get rid of the 40Hz dip. I think it's worth a try.
Hey OCA, great stuff, thanks. So aligning the first tiny peak is no longer the correct approach or is it still valid when using a DM device (6 M max distance to shortest located speaker)?
If you cannot set your hardware for the right distance then an earlier peak and if even that is not possible then aligning IR starts are still your only options. But they will be both compromised alignments.
@@ocaudiophilecan’t you just adjust the phase on the physical sub to change the timing reference if your AVR doesn’t allow much movement?
If your sub was switched to 180 deg phase during measurement, you can gain about 2m distance @ 80Hz by switching it back to 0 deg but otherwise, you'll simply need 2m more of distance.
"Assuming phase switch circuitry itself doesn't add additional system delays"
Hi. We have built a cinema at work(oil-rig), but I feel we doesn’t get the sound right. It’s a 5.4.4 system. Reciever is a Onkyo, so no Audyssey one possible…
What approach would you suggest calibrating this. Minidsp on subs, wireless transfer to back subs. So lots of delay. By the way, one evo run nicely on my laptop for my private system 👍🏻🙂
The easy(easier) way is to measure each sub using acosutic timing reference at the MLP, generating their excess phase responses, applying a 24dB/oct low pass filter to them at 120Hz and then cross correlation align the results. It will give you how much delay each sub will need to reach MLP at the right time. The optimal way is to align all subs to each other at 50Hz with REW's "alignment tool" using "Impulse alignment". This will determine correct polarities and minimize delays. However, with 4 subs you will need to align 2 at a time and align the next with their "aligned sum" and so on. Also, the order you do this will change the results so you will need to check for 12 different combinations. Good luck with that ;)
Woha easy way is to buy new amp😂
But if I should follow one of your videos then?
And this is a three row with 5 seats each row. Is there a point to spread measurements to each seat? I think this will degrade all seats and maybe focus measurements around middle row mid seat
Correct, focused measurement will be less uniform all around but better in the middle, the other will be not so good uniformly everywhere. Focus in the MLP and let the uniformity be handled by the number of subs.
So I’m a little confused
I have Dirac live full version in avr and mini dsp hd 2x4
After aligning subs then aligning to my reference main where do I add delay ?
Do I rerun Dirac and set that delay in the distance of sub in avr ? Or do I let Dirac pick the new distance /delay ?
I will let the final say happen by OCA, but from what I understand this procedure is all about doing it manually using REW. I have Dirac live too, but Dirac is OUT of the picture if you wanna tweak manually, meaning we no longer use Dirac. Here is the procedure in a nutshell - You gotta first time align all the subs, then make a "phantom sub" in REW. Then you time align the speakers one by one (by adding delay to them in the AVR) to that single, phantom sub. AFTER all that you can equalize the speakers by adding filters.
@@rajdude1 since you can’t adjust distance/delay in avr as it is locked by Dirac do I have to factory reset the avr every time and rerun Dirac ? How else can it be done?
@@rajdude1my 2 subs are aligned but I’m stuck as to how to align the phantom sub to the mains,
@@andyv9365 no no. Like I said earlier, (if you want to do this manually, and follow this video) you have to stop using Dirac. You have to use one of the other modes of EQ in the AVR. For example, my AVR, an Emotiva XMC-1 has these presets - Dirac, preset 1 and preset 2. So I first put my AVR into preset 1, and then work on this procedure.
@@andyv9365 That procedure is explained in this video by OCA, skip to 33 minutes into this video
I have now viewed just about all of your videos in just the past week. Fantastic Job and thank you for making them! I have been doing things (the older way) I guess you could say with REW. Any suggestions where to start first? I want to basically do everything over. 7.1.6 system. Three subwoofers as of now. Hopefully will be able to cut that down to two subs when the new one arrives. Should I start with all of the speakers first? Then do the subs? Other way around? Not sure what is the best way to approach this? As of now I recently downloaded the REW equalizer filters and REW Atmos sweeps that you provided the links for. Have a Denon receiver with xt32 and editor app, and minidsp 2x4 hd. Let me know your thoughts on this if you get a chance please. Thank you!
A lot of the videos are for stereo listening and requires a PC as a music player because the filters created require lots of taps only PCs can handle. When all filtering needs to be done in the multichannel receiver, you are bound to use Audyssey (which has only 1024 filter taps) and you can manipulate it by using the Editor app but you cannot do any phase correction for example. I use an integrated stereo amp with Home Theatre bypass property connected to front pre outs of my AVR and also connected by XLR inputs to my PC and Dac. This way, I can add two more channels to my Atmos system and also use the front speakers as a very capable hifi stereo system with any kind of filters I want simultaneously.
Now for your case, connect all subs to MiniDSP and use that as a single sub in the AVR with Audyssey. You can align the subs for relative delays in the MiniDSP using MSO or the method explained here but make sure you don't induce long delays to any sub. The AVR has a 20ms maximum delay limit and beyond that, it cannot synch your sub system to your speakers. You also do not need to use any EQ for your subs in MiniDSP unless you have peaks above 20dB. Then run a careful Audyssey calibration from the app and feed the calibration file to Audyssey One (see my latest video). It will do everything for you in the best possible way.
Align subs in REW with minidsp (not a problem / no low shelf filter or high pass filters in minidsp ), no eq at unless peaks above 20dB (understood). What will the Audyssey One do with the subs below 20hz? I am pretty darn flat to 10hz. Thank you for all of your help! Greatly appreciated!@@ocaudiophile
Audyssey filters start as early as 2.5Hz but anything below 20Hz is kind of ignored. But no worries since you will not be able to hear below 20Hz ;)
what about the tactical response I have now? Using a low shelf filter at about 47hz I believe 0.7 Q with a 6dB rise. I also just tried Audyssey One. I just uploaded a file I had from the editor app. I followed your instructions and I belive i did it correctly but when i watched your video tutorial on Audyssey One the Dr Toole target curve does not look the same? Mine is basically flat. Starts at 24k hz at 75 SPL and ends at about 3 hz which it rises to about 82.1 spl? What did I do? Doe @@ocaudiophile
My apologies, maybe I did it correctly. Looks similar to the one in your video.
I have two subs (different kinds) connected to a NX3000D in front next to my speakers and I'm seated only 2,5m away.
But for some reason I can't seem to get a good flat response.
And when I get something that comes close to the house curve, it sounds very flat.
I'm not sure what I'm doing wrong....
Go for the "Aligned Sum" that yields the highest peaks. Don't forget to try with one sub inverted. You can always create a flat response with filters later.
Thank you for making these videos. Wonder if you can help me with some issues. Cinema room. Three seat rows. Four subwoofers. I aligned them but when trying to timealign to center I get a 25ms delay even when distanse is at max 9meters. 25 ms positive in relation to center. Two subs in back corner have wireless signal to minidsp. What can I do to get subs and center aligned?
And last question: can I trust impulsepeaks regarding to phase? It looks like right speaker have peak in opposite direction to the rest..
thanks 🙂
Even within same brands of speakers impulse peaks may sometimes reverse due to mic position and reflections though rare. Best way to check is in Overlays/phase graphs with all speakers shown. Click "invert polarity" repeatedly for that speaker and check which one has a better phase fit to the rest of the speakers. You can 1/1 smooth all responses to see more easily.
Your subwoofer alignment problem is tough to solve with Denon/Marant units especially when even the actual distances we are talking about are around 9m and wireless connections on top of that. You should maybe go with the "directional bass" mode. At least subs will be closer to where the signals are coming from. You can switch to that mode by using the app even if your AVR is an older model. Let me know what you decide to do.
Directional bass is not available in my Onkyo..
Fysical distance is about 5m to front and 2m to back subs. Any recievers with larger distance adjustments?
You might have it through the app:
audiosciencereview.com/forum/index.php?threads/audyssey-manual-calibration-master-stroke.46120/post-1658127
@@oddkjetil1030
Is this still necessary if im using your A1 Evo script?
No!
Sir,sorry for disturbing you again...
May you pls clarify:-
1. While measuring with your 1M sweeps,what should ideally be the master volume in the receiver set to....(Should it be set to your usual listening db level in my case it is I usually listen my content at -10db)
2. One reason I am asking you is this (while I corrected my laptop sound setting for my UMIk 1): when I was measuring with your 1M sweeps it at even -10db level it reports of clipping and says reducing the sweep level,processor volume setting....
Requesting you for help sir
Thanks and respect for you
1.Yes
2. Rew will not complain from AVR volume. The clipping is because of too much microphone gain. Decrease your mic volume.
Ok sir thanks
thanks OCA, is it best to start with both sub distance set to 0.00 in the avr
Ideally yes or at least all set to the same distance.
Thank you, that probably why I had a 10db peak in one seat, my AVR had distance set by audyssey one sub was 13feet the other 9 feet , my subs are the same distance from the MLP , no delay is really needed when I align them
Nice!
If we are time aligning all speakers and the combined sub response to the center channel which is also my acoustic timing reference, then what is the benefit of aligning the speakers and subs as explained in this video? Thanks
What's explained in the video is time aligning to acoustic timing reference?
@@ocaudiophile I am trying to understand the difference. In the end don't both approaches result in subs and speakers aligned to each other? I am referring to the process you explained in the supreme audyssey calibration video
This video explains various ways to optimize time alignment. Method is not different to the one in Supreme Audyssey video. At the end of the day, there's only one correct time alignment for a given set of subs and speakers. I was going to include a section on how to deal with Audyssey 6m speaker distance limit as this is a very common complaint but that will be covered in a future Audyssey video.@@Rayman-expertsoundpro
@@ocaudiophile Thanks! Makes sense
I'll be looking for that video with the 6m subwoofer limit in the Audyssey ;)
PLEASE HELP. I am trying to wrap my head around this concept. I have two subs in what I call a stereo sub config, where the 2 subs are kept right next to the front main speakers. Room is multi purpose, used for both movies and music. It seems to me I have two options -
1. Align my two subs first. Then align the phantom sub with the main speakers (that is what you seem to be saying).
2. Align the left sub to the L main speaker and right sub to the R main speaker, which this guy seems to be describing ruclips.net/video/yMussZ1C-dE/видео.htmlsi=539ppQzrJftwEZUT
BUT which option is the correct option? Sorry, I am totally confused here 😞
You should align the two subs between each other first. If you have an amp with Audyssey, try A1 Evo which will calibrate everything for you.
@@ocaudiophile thank you OCA! I'll follow this video then. 👍
One more question please...Once I have the phantom sub in REW, should I align it to both L and R mains one by one? Or is there some other method available?
BTW, I have an Emotiva XMC-1, two Rythmik 15" servo subs, Magnepan 3.6r and Bryston monoblocks (also have Magnepan center and surrounds)
You need to equalize left and right speakers to the same target curve and align their impulse peaks. Then you can use the vector average of these 2 to align with the combined sub response for a suitable crossover frequency.
Hi OCA! What has become of you! :) We're waiting for this next tutorial to keep improving :D
A 'game changer' video is coming very very soon!
In the mean time, run a descent 8-microphone position Audyssey calibration with the app and save the calibration file 'as is' in a safe place ;)
@@ocaudiophile it is only for Denon/Marantz where the results can be downloaded?
Audyssey methods work only with Audyssey and some older Onkyo's might also use (I think). There's also a link in AUdyssey ART video description for a script to decode Anthem arc measurements to REW if it helps.
@@ocaudiophile no, I have a Yamaha ;)
@neutronenflusterer9643 Check my manual Dolby Atmos calibration videos.
Wunderbar
Eyvallah!