I had a left and right set up about 50 feet apart in the church. I use map to predict and saw all the cancellations and the flower petals. So we relocate them underneath the stage a half wave length apart My crossover frequency is 125 Hz I have two subs in the middle touching each other then I’ll spread the others to wavelength apart when I did the prediction again, it look like a gigantic pear. And the energy that the audience get now is amazing so I agree with all this that you’re trying to teach and I appreciate you thank you so much.😊
I've been using half the subs I used to use and getting the same or even more power thanks to these useful tips. Thanks for the great work and for the metric spreadsheet, very needed for my portuguese workflow. (feet here are only for wearing shoes :D)
There is literally nothing too nerdy or in the weeds for me. Please always elaborate! This has been an excellent intro to setting up smaller systems man!
Had a gig with the same subs I have now in the "traditional" LR setup and kept hearing/feeling the alleys/valleys and this video completely visualized what was happening. Going to be using a center cluster with them this next time around and I'm very much looking forward to my walk around, with and without people.
This was so helpful, I am just setting up dual subs and ive realised that the cardioid option is the , one I should adopt , as I'm in a brewery and there is a row of tanks behind the stage area, I have built the subs inside two large rum barrels and was going to put them both on the same cradle after watching this they need to be on separate cradles to really increase my options, thank you for explaining things so clearly
This Saturday I tried the two subs next to each other spacing 151cm and it sounded awesome! (I used to do a left right setup and not think about it at all.) I have four passive speakers for which i used the matrix on my x32 as a crossover as well as a spare monitor as a front fill. The whole thing sounded incredibly clear and balanced and i got compliments on how it all sounded. You could tell the shape you modelled just by where people were standing in the room. Your videos have given me such a boost in the quality of my work that i now feel that i could actually charge more for doing these kinds of shows. Later on a dj played a set using my gear and he too was impressed by the sound, lowend and volume of it all (and he used the front fill as a monitor so i didnt have to do any on the fly patching.) I'm so grateful for your videos and how it helped me jump forward in knowledge and understanding. Thanks a lot !
love the content. The spreadsheet shilling does get a little tiresome, but these videos are pure gold. I've probably learned more watching the videos you've made in the past week than I have about sound in months. I'm a 18 year old currently attending college while trying to get more into the event production game. Currently doing events with fraternities and the local area. I'm in charge of sound for our business, so learning more and more about the physics of sound and knowing more about speakers is super helpful.
Glad you're enjoying the videos! I'll have some more varied free resources coming soon. The spreadsheet is helpful to folks, but you're right that I mention it in a large percentage of my videos.
Hi Michael, great video! Can you please consider doing one talking about portable column array speakers for portable dj's as well? Myself and many people I've seen online have doubts in relation to many aspects: they advertise a very good horizontal range like 120º, they almost always pack a small sub like 10, 12 inch (do those pump out enough spl?) and some systems like the maui 28 have built in processors for cardiod setups (would that help dj's), would they be good in a outside scenario. But also they advertise that they can be combined in pairs, so what distance from one another should they be? can we use a different sub with them? Hope you find the time!
@@MichaelCurtisAudio … so would I do this same center coupling with my two passive Yorkville LS1208 scoops because normally I would do the left & right set up with a qsc 15” on each one inside big ballrooms and it would sound pretty good to me I’ve never center coupled my big scoop’s before but I always couple my powered EV Etx’s and they always hit so much harder!
Great video. An additional option I use is to stack the two subs on the left side at our church where the drums and bass are located. Adds a bit of stage location to the sound in the room and when people think the the low end is too loud they can move to the right side 🙂 I happen to be using D & B Audiotechnik cardioid subs which greatly simplifies things greatly
Thanks mate, a few videos ago (the one about column speakers one) I asked you which one would you prefer: one double driver sub or two single driver sub, as I was building a small PA. I followed you advise and ended up with two single driver subs. This video is gold for me, I will definitely experiment with the different configurations. Also thanks for the metric version of the spreadsheet!
Hi Michael, I tried different inverted gradient stack configs in Ease Focus 3 and they all seemed to disagree with your delay calculations: They all ended up looking like a super cardiod pattern (in your video 16:43 as well there was a little blob projecting backwards). To mathematically investigate the issue I plotted the sinwewaves radiating from the subs in a math software. My result is that we have two options, a) to go for max summation in the front, or b) to go for max cancelation in tha back. a) is achieved by calculating the delay as described in your video (adding the horizontal driver displacement as a delay the bottom sub) b) is achieved by subtracting the horizontal driver's displacement from the half-cycle of the crossover frequency. In case of 100 Hz that would be 5ms minus the driver displacement in ms). Mathematically we can solve this set of equations for a and b to be true, so we have both max summaton in the front and max cancelation in the back. For this to work, both the horizontal driver displacement and the delay added to the bottom inverted sub have to be equivalent to a quater cycle (of the crossover frequency). For 100Hz that is 2.5ms (or about 86cm) displacement and delay. Thanks for your video!
I watched so many videos to find this answer that I was looking for. Thank you for making this. My question was: When should I use the phase change button (180 degrees). Tell me if I wrong but I believe the answer is: When using a Cardioid set up, but don't forget the delay. Thanks again.
Glad it was helpful! A slight tweak to your answer: cardioid sub setups is one use case for inverting the polarity of the sub. Other time you might use it is to make the phase response of the sub better marry up with a main. Those are the two main use cases.
Michael. So, as a low end sound guy, could you show what these positions would look like if I had 2 of the QSC cardioid subs… what do the power alleys etc look like if each sub is a self contained cardioid sub? I’ve always seen the dual 12” cardioid sub set L/R with the poles screwed into the sub and the top perched up there… it seems that this use might keep bass off the stage, but create the same alleys for the audience. So good for noise control on stage, but similar issues as single subs spaced L/R for the audience…is this correct. THANK YOU for this content, very educational!
Thank your for your amazing explanations !!! I have a little question : is it possible to used 2* 15" Sub combined with 1 or 2* 18" Sub ?? I would love a video explaining the advantages and disadvantages =)
Half wavelength crossover center with JBL SRX828SP (dual 18). Assuming an 80hz crossover, lets call a half wavelength 7ft... where physically would I be measuring from on dual 18s, the center of the box? The boxes are 47.5" wide, so if placing 2 subs center-stage with 7-foot spacing from their centers, that would mean roughly 3-foot gaps between the left and right sub stacks is the max before the pattern starts to break apart, with an 80hz crossover. Am I on? Biggest thing I get hung up on with these spacing talks, is there's never mention on where to place the tape measure, especially with wide dual-18" subs.
i have 2 12s in my volvo station wagon. with the back seats down its like a tiny empty room. the bass was best with them both next to each other in the back left corner, instead of one in each corner. only a two foot movement made a big difference.
Great video, thanks! Probably, aligning the rear sub more precisely in the inverted gradient array would yield to better results. Also, lowering its level a little bit might help
@@MichaelCurtisAudio thanks. I'm currently working on a design for a church where the subs can't be in front of the stage, so I'm considering putting them under it and use a cardioid array in conjunction with bass absorption and detailed dimension of this cavity they would be in. It's a hard one
@@Labaris Cardioid arrays unfortunately fall apart when under a stage. There's too many reflections for the careful conditions of cancellation to occur : /.
@@MichaelCurtisAudio I figured that was probably the case, that's why I was thinking about designing finely-tuned bass absorbers inside the cavity (the space under the stage). But really, it doesn't seem to be a good idea actually. Thank you for your insights!
Hey Michael great video! One question though, at 13:54 you talk about delaying the rear speaker. My brain says delay the front speaker so the sound waves travel together. Could you explain this! Cheers from the UK!
Hey Michael, I think you were speaking to this at the end of the video referencing a 7th setup. But when you delay and flip polarity on the rear speaker in the cardioid setup, doesn't that mean your kick signal will be out of phase? Sure the peaks and troughs will line up, but you'll have a delay between transients on your rear and front sub. Isn't that a concern? or is it less of a concern than not getting the broadband rear cancellation as you mentioned when comparing to delaying the front sub with no polarity flip. Thanks for all your content! Super helpful.
Michael @15:15 you said it was 2.17ft multiply by .88 gives you 1.909ms of delay but then your spreadheet you showed 2.17ms of delay...uh ? am i missing something ?
Do you have any similar tutorials showing these graphs in a smaller indoor venue with wall/ceiling reflections being accounted for? Are the sound peaks/valleys in a left/right sub config really all that noticeable? For the vast majority of venues we play, it’s the most practical physical setup. Will a cardioid setup against a wall on one side sound all that much better?
Hi Michael. This time I watched the video looking at the distance and the colors. how real is this software? in particular (which I also tried) is that the inline cardioid has more energy. I see about 155 feet with the light blue versus 135 feet of the frontback cardioid. It's true that LR generate cancellations but I see light blue even at 180-190 feet. Are there any calculations that need to be done? Compromises
So glad i just found you and subscribed, i've been running audio for many years but just with a simple point source system and some home made sub cabinets with a dbx driverack and passive amps (ALL CROWN MACRO K2 and XTI, but i have never really learned the intricate math behind why some shows work and some suck. i dunno if i can do much with just a basic driverack or learn more on how to position my stuff.
You can do plenty with the just the driverack! That unit is more gear towards aligning and tuning crossovers within a single enclosure, not necessarily a full rig, but it can work for that minus any serious output delay times.
so I have 2 Qsc k12.2 tops and 2 Qsc KS212C subs and i always place them left and right of my dj set up (1 top & 1 bottom) so is it better to put both of my tops on my left & right and both subs facing forward together/side by side in front of me?
Really helpful video, has given me pleanty of ideas for next gig. Just a quick question if I’m trying to utilise a inline gradient cardioid setup. How do I add delay to one of the subs. I’m pretty new to this so might seem like an obvious question 😂. But I’m using 2x Mackie 18s subs and 2 x thump 15a loudspeakers. Would it involve adding delay through a mixer ???
You would need some sort of DSP to do that. You could use the internal prossesing power of an digital mixing console (if that's what you're using) or an external DSP/Speaker management system (like the Behringer Ultradrive or a DBX DriveRack). If you habe any further questions, don't hesitate to ask, I or the rest of the comunity will try our best to answer... I hope this helps :)
I have another question. Why have almost all manufacturers abandoned any other designs other than bass reflex or bandpass? because the drivers have already become too powerful to spend the mass and volume of acoustics on design?
I've been doing end fire cardioid almost always if I have two subs available... it gives even sound across audience and cleans up the stage and has very low setup and processing requirements. To do something more fancy one'd need thee or more subs and more processing :) I hate spaced pair subs that are very common...
Impressive! Question: if you only have 2 sub in a home theater 20’x30x20 (WLH) what would be the response if you put the subs diagonally? That is front right, back left.
I'm a bit of a dinosaur and have not mixed sound since the Mackie analog boards were popular. Our pastor found out I used to do this and asked if I could help figure out how to add more bottom end to their system. They have a JBL powered subwoofer, i believe its the PRX series either a 15 or 18. The sound booth is situated on the side of the auditorium which I know is far from optimal and the sub sits next to it. After watching your video my question is can one sub work ? I now know we need to move it to the front center but I don"t know if we can rig this to the ceiling. Our only other option would be on the stage center but from what I'm understanding this is not good? The room is not huge and its wider than it is long.
If you're not able to put it center, put it in front of your stage off to one side. Like you said, optimal would be to fly it center. Even better would be to fly two of them in the center and space them 5ft apart of so so you can narrow the coverage.
What is the best space to a hard wall for a 2 Subwoofer Cardiod - inverted gradient stack? If they are both away from the wall, the best space is as close as possible. But How is the best space, if one is facing to the wall?
If working with rear ported bass reflex, how would you calculate using an inline gradient or a stacked gradient deployment? Generally, how would rear ported subs react as a whole in any configuration?
Can you do a video about DJ Line array systems like the Bose L1 pro 16. Since the subs are part of the line array I usually put one on each side of my DJ booth which is only about 6-8 long. By doing this am I causing alleys on the dance floor? Should I put the two speakers in front of my close together and have them slanted out or will the high end speakers in the system cancel themselves out because they are too close?
In your case I would still put the two columns separate. I'd probably toe your speakers outward some more since the high frequency coverage is very wide. But I also understand you want as much of the energy to go to the dance floor and not other places in the room. With your subs about 6-8ft apart you are getting some narrowing of the low end coverage, for sure.
If the stage isn't too wide I'd say it's just fine. If you have a wide stage the low end can feel "lopsided" from an imaging standpoint. I'd test it out - try a LR vs a side stack and see which of the tradeoffs you would rather live with.
In the inline gradient cardioid setup, why is the speaker closer to the stage being delayed, and not the one closer to the audience? Is this because the intention is to have the wavefronts sum (and cancel, being out of phase) at the stage position?
Great question! This video goes in more depth on that - ruclips.net/video/e90v1NVT7bQ/видео.html You got the first half of the question right. This recipe creates cancellation in the back, but we do also get summation in the front. The rear sub arrives a half wavelength late at the sub's center frequency (this is dependent on your spacing), but is now polarity inverted, so it flips the comb filter upside-down and has summation throughout the sub range. You just have to be careful and not space them too far apart or the comb filter will bandpass your subs too much. Farther spacing is for systems with lower crossover frequencies.
Hey Michael, thanks as always! For the halfwave spaced setup: When you say "up to" the crossover frequency, do you mean by distance or frequency? For example, if my crossover is 80hz, is my spaced limit 7ft? Or can i space them more @ 11ft to boost 50hz?
Why you don’t consider an ‘end fire’ setup in a situation like that? That’s by far the best config in terms of efficiency, phase response and alignment in the front while allows you to have some rejection in the rear.
End fire is definitely a great option to have in the toolbag. I actually deployed an endfire array just yesterday. The reason why I didn't include it here is that I rarely have the real estate necessary to do ground stacked end-fire arrays, so have to default to more compact solutions like gradient stack. Gradient configurations also have a more stable coverage pattern over frequency when compared to end fire.
the thing I wonder the most about sub setups is how much max spl for most of audience is lost for each setup compared to just putting the 2 together to get that full 6db increase because a lot of times I need to get The most max spl out of my RCF Dual 18”’s because I don’t have enough
I have watched this video a bunch of times. it is gold , thank you! I had a question. for the dual center, side by side Omni pattern and the half wavelength setups, do the same principles apply at a higher Crossover frequency. for example would this still apply for a 180hz cross over with FOH tops on each side of the room/stage and the subs in the middle? and would that cross over point (180hz) be too harsh? the cross over point is common on a popular Column array vendor kit. the cross over point is set at factory and can't be adjusted, but wonder if separating the tops from the subs and setting them up side by side would help focus the low end on the dance floor. thanks in advance. I've been going through your other videos, very cool stuff
Yes, same principles would apply! But do keep in mind that we want the same tonality everywhere. So, you could focus the sub on the dance floor, but you don't want folks standing away from the dance floor to only hear top end, then hear a big tonality change when they walk on the floor.
Cardioid Subs Explained For Normal Audio People - ruclips.net/video/EgHK1s7SzIE/видео.html Cardioid Sub Workshop | Inline Gradient - ruclips.net/video/e90v1NVT7bQ/видео.html
OK thanks, I'll take the time to watch that with thought. I guess I have had few misconceptions; firstly I thought that back-facing a sub reverses the phase, but it's not dipole speaker... Then I thought delay+distance are mandated by summation frequency wanted, but actually delay compensates the distance. I guess that distance is mandated by summation frequency then?
For now I'm focusing on live setups, but a lot of these principles still transfer. I'd check out Jesco Lohan at Acoustics Insider for small room acoustics and speaker setups.
Could you do an analysis over what the coverage be if subwoofers were up against a brick wall? Also, what would the response be if the subs were about 15 or 20 feet out in front of a brick wall?
Great questions, John. You can think of any hard reflective surface like a brick wall like an audio mirror. Any sound going into it will be reflected back at the same angle of incidence. Given that, it's usually best to have your subs as close as possible to boundaries or at least 10ft/3m away so you can avoid speaker boundary interference (cancellations that happen at the speaker due to the reflections).
In relation to the inverted gradient stack center setup, how do you find the distance between the drivers when you can’t see the drivers, like in the QSC 212? If the two subs are identical, it just the depth of one sub?
I copied and pasted it from another youtube channel that has the pill and I keep it in a code block in Notion where I type out my RUclips descriptions.
I'm not able to center cluster my two QSC KS118's (cardioid) because I have a video DJ booth. Is it OK if I put them on one side? My entire setup is no wider than 12 feet. Also, is it OK to cover the subs with a cloth covering to help conceal them?
You are amazing I really appreciate all that you put out there. I'm trying to set up a inverted gradient stack. If your soundboard/subs don't have a built in delay, what kind of hardware would you use if software isn't an option?
Thanks for the organized information. Can you clarify how dual 18 subs play into this? What happens when they are side by side giving you four 18s somewhat evenly spaced (space between speakers in the box and end to end spacing between boxes). Where do you measure from when doing a half wavelength setup? Thanks in advance!
Hey, Michael. The big difference with the dual 18" cabs vs single 18" is that they're twice as wide, therefore creating a wider baffle and line length. So, placing two dual 18" cabs next to each other would have roughly the same width as four single 18" cabs. The same principles apply - a long line of speakers creates a narrower pattern. As far as measuring the half wavelength, as long as you choose the same reference point on each enclosure you'll be in good shape. It could be the center of the box, the center of one of the woofers, or the sides of the enclosure, just as long as the boxes are identical and you measure from a consistent point.
Let's say there is no stage and the band is playing on a concrete pad. Is it still best to do a center sub array if they don't mind seeing a sub or two in the center or is LR the best way to go to avoid looking awkward?
Hi Michael! How do I align phase of side tops with center sub cluster? Should I just put measuring mic in the center of venue and align tops one by one?
Great tutorial thank you, i would like to ask, lately djs and performers prefer to have subs on stage for monitoring purposes, how does having subs on stage affect the cardiod behaviour setup of the FOH subs?
Thank you so much for your videos! Is there a way in this software that you use, or can you recommend other software, for plotting subwoofer effectiveness in the way that you do here but for inside environments? I.e. the addition of walls and how the reflection from them might cause another dimension of phase cancellation. Thanks again!!
If I set my subs center either side by side or stacked and the stage is tall (about 5’) and has a brick wall holding up the stage, how does the hard surface behind the subs affect the sound?
Hi Michael! So...if the subs are placed up to one half the wavelength of the crossover point (I'm using 80 Hz), you're still able to avoid power alleys and valleys? I'm I getting that correct?
So I plan on running a half wavelength crossover @100hz.. dual ls801p and ef500p yorkvilles on sticks .. I plan on using your tuning methods, but most of your videos you talk about taking measurements on axis with the mains. I'm little confused as what to do when it comes time to measure the subs. Do I turn off the opposing main and lower the sub outputs -6db like in the attaway video.. But that was also a L/R setup with no coupling, so I'm unsure.
Great question! If my subs are on the ground I usually end up setting the level of my subs about 50-75% of the way back in the audience. Then I time align my subs on-axis with the mains (center sub or LR setup) 75% of the way back in the audience plane.
Hello Michael! Can I put inverted stacked subs pattern horizontal? I meant two subs on the floor, one of them facing to the front and one to the back. Thanks!
Absolutely, but the directionality of the sub will change. If you draw a line from the center of the rear woofer to the front woofer, that will be the direction of the wavefront, so it'll basically shift off axis 45° or so.
Mike, Need to know what program/app you might recommend in place of MAPP 3D that will allow you to insert speaker parameters to develop a similar map. I downloaded the program it worked great, but unable to use the available speakers for the small venue I was in. I would love to be able to generate a map of how things are right now, and see how it would look after moving the speaker placements and angles.
@@MichaelCurtisAudio Thanks, I actually downloaded it and trying to work through it. Unfortunately I tried downloading the Data direct from JBL, but Ease is saying the file with the speaker parameters is incompatible. I may end up doing it all manually. Already took space measurements, and using Pink noise have dB levels from 10 Points as well as images of the frequency spectrum from those 10 points. So while I may not see the exact changes by trying to move things around I can see issues in the current setup.
Hi Michael, great video, just one quick question. I am a mobile DJ, do a lot of school dances, large gyms, I bring 2 Alto 18" subs, I used to put them LR but now I put them together on one side and I have 2 Alto 15" main speakers on top of them. Sound difference from when they were LR of my DJ table is way better. My question is since the students are usually right on top of my table asking for requests, i really cannot set them up cardioid so is this the best set up using the 2 18" subs and 2 15" mains, or should I consider some other arrangement for large gyms? Thanks for the info, I am a lifetime subscriber...
Question I have two rcf hd32's and two rcf 702's which i place in front of the stage Thinking of purchasing another 702 sub is it best to position a sub under the hd32 tops and a sub in the middle: 15 "subs are to big to carry
Help a newbie here. Currently I have my tops and subs and an analog mixer, primarily for dj type use. What equipment can I start with that has the processing power to add the appropriate delays for a cardioid setup? I'm not totally clear on if I'd need a fancy (expensive) digital mixer or what....
I'd check out the t.racks DSP 408 from Thomann - www.thomannmusic.com/the_t.racks_dsp_408.htm I personally own one and it has a few quirks, but overall an sturdy and affordable unit.
Very nice video. Still need one thing though :). In your very nice sims. The rear wall is none existing (looks mostly like free space). But in most cases there will only be something like 1-3 meters from rear wall to subs. This must have a massive effect as these could also cancel out some wavelengths?
Great point, Philip! Yes, in the "real world" your acoustic environment will have a massive effect on your low end. I should have mentioned that as a caveat, but my intention with this video was start with the "building blocks" of these setups, then throw them into other scenarios/limitations in later videos. I definitely should have mentioned as well that hard stage fronts are a no-go when using cardioid setups in front of them.
@@MichaelCurtisAudio Interesting! can you give a short explanation why a cardioid setup infront of a wall/hard stage front is a no-go? is it because the cancellation "mirrors" to the front and messes with my summed signal? My first thought was that it will improve the sound because of reduced reflections... thank you in advance!
@@mongotoffelLP You can think of any hard boundary near a speaker creating a "mirror image" reflection at the angle of incidence of the original wave bouncing off that surface. With cardioid, even though you're getting less energy going rearward, the reflection messes with the specific parameters needed to create that rear cancellation. The energy bouncing off the back wall behind it adds more energy at a different time and negates some of the cancellation effects.
Thanks, Evan! I'd say it would probably be the center side-by-side setup. With just two subs having them as closely coupled as possible gets the maximum possible SPL out of the rig. It also gives the widest coverage pattern, which is often needed in outdoor setups. If the stage doesn't have a hard front and the subs I have are efficient (not needing to drive them hard to get the desired SPL), then I'll do an inline gradient seutp.
Again, great video. Love using the cardioid setup especially indoor. But. Does this consider ground coupling effect or is it for a system that’s flown?
In this model I didn't have the floor "turned on" as a boundary to have in the predictions. However, you'll still see similar results both with a flown and groundstacked inline cardioid setup.
Super helpful video Michael! But I had a question. I'm working with four subwoofers now, a dual 18 and two 18 inch single subs. I've been placing them in the middle at my events, will it have a similar effect to the two subs being coupled in the middle? I would love some advice about how to place these things for maximum output to the crowd! :)
Hey Michael one thing I cannot wrap my head around. For example, if the stacked center (omni) is generating around -30 db at 130ft on axis, how come the inline gradient setup is able to generate around -24db at the same position. Both of this cases would be in maximum summation at that position (Right?). I understand how cancelation works to 'direct' the sound and one may think that 'energy' is conserved, so if you have no energy out in the back, a natural conclusion would be there will be twice as much going to the front. But I think that this is not correct. For example, if you consider the extreme case of putting both subs in the same position but with 180deg phase difference, that would result in complete cancelation, in other words zero acoustical energy. I hope it makes sense, I will keep thinking about it...
Hey, Diego. Very keen eye and insightful question! You've actually caught an error of mine. In the very first setup, with the two stacked center subs I actually forgot to add the second sub "on top of" the first in the 2D software. Even though it would still look the same before the prediction, having two subs would definitely affect the SPL measurement. Given that, you saw a -6dB drop in the first example compared to the others. -6dB is the same as half as much level, which is the same as 1 sub vs 2. Great catch! Long story short, if I had done the first prediction correctly you would have seen the same SPL level at 130ft on-axis.
Hello, Michael! I have a strange situation: when I use aux fed subs, I have poor/low volume from my subs . This happens when kick drum is playing-subs are peaking but the sound is low. But when I play music from laptop, subs work loud and much better! Could you please help with your advice? What could it be? Thank you so much! Victor.
You can do it side by side, but it'll change the directionality of the array. If you draw a straight line from the center of the woofer of the rear sub to the center of the woofer of the front sub that's the direction the sound will move.
How would you go about placing two subs in a very wide room? If placed as a center cluster the throw will be narrower. So will it drop off at the sides?
i recently did an outdoor show. Audience area is size of a football field. I have two dual 18. I put them together touching. had a terrible valley. it was like you turned them off. it was narrow. i started to move them apart and kept checking it. the valley just got wider and wider. it was just dead. we usually do the left right sitch, and have that valley, but not as bad as with them pushed together. my setup did not match these diagrams at all. PS I was right in front of a concrete stage. what gives?
It sounds like to me one of your subs had a polarity inversion somewhere in the chain. They were "fighting" eachother when they were close together because you essentially had a copy of the sound wave coming from the same point in space, but inverted, therefore the sound from your subs was in a silent stalemate.
I was thinking that. They were purchased used. Who knows if some knuckle head "fixed"them at some point in time and reversed the wires. I know this because i had another set and that was an issue. Ill check all my wiring. Doing the same place this weekend again. Thanks for the reply. I really enjoy your videos. I run passive gear. So i don't have fancy built in polarity switches. Lol i guess the polarity built in to x32 would work. When measuring side to side placement...where do you measure from? Ctr to ctr? Outer edge? Where do you get the 5.6 feet? Can you build a dual 18 with a third facing rear?
Two questions: - If you stack subs, is there any positive or negative impact (like more pressure in the chest, ... of the audience)? You did do a 2x2 monostack in your other video. - What if you do angle sub arrays/stacks towards a center point in the audience? :) I often see that in small clubs with L/R stacks. Thank you! :)
If you stack the subs you will slightly narrow the vertical coverage pattern, which could focus the low frequencies a bit more towards your audience. This affect is much greater with a larger stack of flown subs. Angling the subs if you're not doing a cardioid setup or working with a sub with built in cardioid directionality will not change the energy in the center. Low frequencies radiate out omnidirectionally from subs.
Love the content. The visuals are helpful and I probably need to brush up on my math. I'm in a room similar to your drawings. Our church meets in a 60'X90' room. We have two Subs and four k12.2. How would you place these for best coverage? Any thoughts on drive-racks?
I'd check out these videos for insight on best speaker coverage placement. Long story short, divide the audience in half and have each K12.2 fire down the middle of its own zone. Fly the speakers if you can. If not, get their trim height as high as possible. I'd do two flown center subs, inline gradient cardioid if possible: ruclips.net/video/OeaMtRvIysM/видео.html ruclips.net/video/pNkhxnFNUNU/видео.html And here's some affordable drive systems/DSPS to look at: www.thomannmusic.com/the_tracks_compressors_gates_de-esser.html
New lessons... Subs in the middle and raise my tops higher. Thank you for this.
You are officially my sound tutor.
I had a left and right set up about 50 feet apart in the church. I use map to predict and saw all the cancellations and the flower petals. So we relocate them underneath the stage a half wave length apart My crossover frequency is 125 Hz I have two subs in the middle touching each other then I’ll spread the others to wavelength apart when I did the prediction again, it look like a gigantic pear. And the energy that the audience get now is amazing so I agree with all this that you’re trying to teach and I appreciate you thank you so much.😊
You're very welcome!
@@MichaelCurtisAudio I wish I can show you pictures of the way it came out.
@@noelbulls8628 My email address is on my website. Feel free to drop me a line there.
@@MichaelCurtisAudio ok thanks
I've been using half the subs I used to use and getting the same or even more power thanks to these useful tips. Thanks for the great work and for the metric spreadsheet, very needed for my portuguese workflow. (feet here are only for wearing shoes :D)
You are very welcome. And about time I got around to creating a metric version ; ) I'm glad that's been helpful to you.
There is literally nothing too nerdy or in the weeds for me. Please always elaborate! This has been an excellent intro to setting up smaller systems man!
You're very welcome!
Had a gig with the same subs I have now in the "traditional" LR setup and kept hearing/feeling the alleys/valleys and this video completely visualized what was happening. Going to be using a center cluster with them this next time around and I'm very much looking forward to my walk around, with and without people.
Let me know what you find!
This was so helpful, I am just setting up dual subs and ive realised that the cardioid option is the , one I should adopt , as I'm in a brewery and there is a row of tanks behind the stage area, I have built the subs inside two large rum barrels and was going to put them both on the same cradle after watching this they need to be on separate cradles to really increase my options, thank you for explaining things so clearly
This Saturday I tried the two subs next to each other spacing 151cm and it sounded awesome! (I used to do a left right setup and not think about it at all.) I have four passive speakers for which i used the matrix on my x32 as a crossover as well as a spare monitor as a front fill. The whole thing sounded incredibly clear and balanced and i got compliments on how it all sounded. You could tell the shape you modelled just by where people were standing in the room. Your videos have given me such a boost in the quality of my work that i now feel that i could actually charge more for doing these kinds of shows. Later on a dj played a set using my gear and he too was impressed by the sound, lowend and volume of it all (and he used the front fill as a monitor so i didnt have to do any on the fly patching.) I'm so grateful for your videos and how it helped me jump forward in knowledge and understanding. Thanks a lot !
love the content. The spreadsheet shilling does get a little tiresome, but these videos are pure gold. I've probably learned more watching the videos you've made in the past week than I have about sound in months. I'm a 18 year old currently attending college while trying to get more into the event production game. Currently doing events with fraternities and the local area. I'm in charge of sound for our business, so learning more and more about the physics of sound and knowing more about speakers is super helpful.
Glad you're enjoying the videos! I'll have some more varied free resources coming soon. The spreadsheet is helpful to folks, but you're right that I mention it in a large percentage of my videos.
@@MichaelCurtisAudio the spreadsheet is helpful, font listen to this fool
I can't get enough of these videos
Thanks a ton, Nick!
Hi Michael, great video! Can you please consider doing one talking about portable column array speakers for portable dj's as well? Myself and many people I've seen online have doubts in relation to many aspects: they advertise a very good horizontal range like 120º, they almost always pack a small sub like 10, 12 inch (do those pump out enough spl?) and some systems like the maui 28 have built in processors for cardiod setups (would that help dj's), would they be good in a outside scenario. But also they advertise that they can be combined in pairs, so what distance from one another should they be? can we use a different sub with them?
Hope you find the time!
Thanks - It shows that you can make big low-end improvements with the most basic setup, without buying more stuff.
Exactly! Even with just two subs you have a lot more control than you would think.
@@MichaelCurtisAudio … so would I do this same center coupling with my two passive Yorkville LS1208 scoops because normally I would do the left & right set up with a qsc 15” on each one inside big ballrooms and it would sound pretty good to me I’ve never center coupled my big scoop’s before but I always couple my powered EV Etx’s and they always hit so much harder!
Great video. An additional option I use is to stack the two subs on the left side at our church where the drums and bass are located. Adds a bit of stage location to the sound in the room and when people think the the low end is too loud they can move to the right side 🙂 I happen to be using D & B Audiotechnik cardioid subs which greatly simplifies things greatly
Great idea. And yes, natively cardioid enclosures definitely help simplify things.
Thanks mate, a few videos ago (the one about column speakers one) I asked you which one would you prefer: one double driver sub or two single driver sub, as I was building a small PA. I followed you advise and ended up with two single driver subs. This video is gold for me, I will definitely experiment with the different configurations. Also thanks for the metric version of the spreadsheet!
You're very welcome!
Hi Michael, I tried different inverted gradient stack configs in Ease Focus 3 and they all seemed to disagree with your delay calculations: They all ended up looking like a super cardiod pattern (in your video 16:43 as well there was a little blob projecting backwards). To mathematically investigate the issue I plotted the sinwewaves radiating from the subs in a math software. My result is that we have two options, a) to go for max summation in the front, or b) to go for max cancelation in tha back. a) is achieved by calculating the delay as described in your video (adding the horizontal driver displacement as a delay the bottom sub) b) is achieved by subtracting the horizontal driver's displacement from the half-cycle of the crossover frequency. In case of 100 Hz that would be 5ms minus the driver displacement in ms). Mathematically we can solve this set of equations for a and b to be true, so we have both max summaton in the front and max cancelation in the back. For this to work, both the horizontal driver displacement and the delay added to the bottom inverted sub have to be equivalent to a quater cycle (of the crossover frequency). For 100Hz that is 2.5ms (or about 86cm) displacement and delay.
Thanks for your video!
dude these are phenomenal tutorials thank you for making em!
I watched so many videos to find this answer that I was looking for. Thank you for making this. My question was: When should I use the phase change button (180 degrees). Tell me if I wrong but I believe the answer is: When using a Cardioid set up, but don't forget the delay. Thanks again.
Glad it was helpful! A slight tweak to your answer: cardioid sub setups is one use case for inverting the polarity of the sub.
Other time you might use it is to make the phase response of the sub better marry up with a main. Those are the two main use cases.
Michael. So, as a low end sound guy, could you show what these positions would look like if I had 2 of the QSC cardioid subs… what do the power alleys etc look like if each sub is a self contained cardioid sub? I’ve always seen the dual 12” cardioid sub set L/R with the poles screwed into the sub and the top perched up there… it seems that this use might keep bass off the stage, but create the same alleys for the audience. So good for noise control on stage, but similar issues as single subs spaced L/R for the audience…is this correct. THANK YOU for this content, very educational!
Thank you so much for this tutorial. Wonderfully explained! It helps out greatly for the live shows!
Bro , i felt like i learn so much waw thank man keep up the great work killer video
Thank your for your amazing explanations !!! I have a little question : is it possible to used 2* 15" Sub combined with 1 or 2* 18" Sub ?? I would love a video explaining the advantages and disadvantages =)
I would like this answer too!! I’m in the exact same situation
Love your content and the passion towards making your video 😊
Thank you so much!
Half wavelength crossover center with JBL SRX828SP (dual 18). Assuming an 80hz crossover, lets call a half wavelength 7ft... where physically would I be measuring from on dual 18s, the center of the box?
The boxes are 47.5" wide, so if placing 2 subs center-stage with 7-foot spacing from their centers, that would mean roughly 3-foot gaps between the left and right sub stacks is the max before the pattern starts to break apart, with an 80hz crossover. Am I on?
Biggest thing I get hung up on with these spacing talks, is there's never mention on where to place the tape measure, especially with wide dual-18" subs.
i have 2 12s in my volvo station wagon. with the back seats down its like a tiny empty room. the bass was best with them both next to each other in the back left corner, instead of one in each corner. only a two foot movement made a big difference.
Somebody please get this guy a bottle of water. lol
amazing clear explanation ... I'm going to apply this for sure
Great video, thanks! Probably, aligning the rear sub more precisely in the inverted gradient array would yield to better results. Also, lowering its level a little bit might help
Yes, always verify in the field since the wraparound path from the front sub to the rear will change depending on cabinet depth, etc.
@@MichaelCurtisAudio thanks. I'm currently working on a design for a church where the subs can't be in front of the stage, so I'm considering putting them under it and use a cardioid array in conjunction with bass absorption and detailed dimension of this cavity they would be in. It's a hard one
@@Labaris Cardioid arrays unfortunately fall apart when under a stage. There's too many reflections for the careful conditions of cancellation to occur : /.
@@MichaelCurtisAudio I figured that was probably the case, that's why I was thinking about designing finely-tuned bass absorbers inside the cavity (the space under the stage). But really, it doesn't seem to be a good idea actually. Thank you for your insights!
Hey Michael great video! One question though, at 13:54 you talk about delaying the rear speaker. My brain says delay the front speaker so the sound waves travel together.
Could you explain this!
Cheers from the UK!
Hey Michael, I think you were speaking to this at the end of the video referencing a 7th setup. But when you delay and flip polarity on the rear speaker in the cardioid setup, doesn't that mean your kick signal will be out of phase? Sure the peaks and troughs will line up, but you'll have a delay between transients on your rear and front sub. Isn't that a concern? or is it less of a concern than not getting the broadband rear cancellation as you mentioned when comparing to delaying the front sub with no polarity flip. Thanks for all your content! Super helpful.
Michael @15:15 you said it was 2.17ft multiply by .88 gives you 1.909ms of delay but then your spreadheet you showed 2.17ms of delay...uh ? am i missing something ?
Great love it, have you done any test comparisons with folded horn configurations?
mobile DJ here. This is amazing. Super helpful.
You're welcome!
Great video sound advice no pun intended. Lol congratulations on the new borne
I'll take it : ) Thank you so much, he's about to turn 1 this weekend.
Do you have any similar tutorials showing these graphs in a smaller indoor venue with wall/ceiling reflections being accounted for? Are the sound peaks/valleys in a left/right sub config really all that noticeable? For the vast majority of venues we play, it’s the most practical physical setup. Will a cardioid setup against a wall on one side sound all that much better?
Hi Michael. This time I watched the video
looking at the distance and the colors. how real is this software? in particular (which I also tried) is that the inline cardioid has more energy. I see about 155 feet with the light blue versus 135 feet of the frontback cardioid. It's true that LR generate cancellations but I see light blue even at 180-190 feet. Are there any calculations that need to be done? Compromises
So glad i just found you and subscribed, i've been running audio for many years but just with a simple point source system and some home made sub cabinets with a dbx driverack and passive amps (ALL CROWN MACRO K2 and XTI, but i have never really learned the intricate math behind why some shows work and some suck. i dunno if i can do much with just a basic driverack or learn more on how to position my stuff.
You can do plenty with the just the driverack! That unit is more gear towards aligning and tuning crossovers within a single enclosure, not necessarily a full rig, but it can work for that minus any serious output delay times.
so I have 2 Qsc k12.2 tops and 2 Qsc KS212C subs and i always place them left and right of my dj set up (1 top & 1 bottom) so is it better to put both of my tops on my left & right and both subs facing forward together/side by side in front of me?
Really helpful video, has given me pleanty of ideas for next gig. Just a quick question if I’m trying to utilise a inline gradient cardioid setup. How do I add delay to one of the subs. I’m pretty new to this so might seem like an obvious question 😂. But I’m using 2x Mackie 18s subs and 2 x thump 15a loudspeakers. Would it involve adding delay through a mixer ???
You would need some sort of DSP to do that. You could use the internal prossesing power of an digital mixing console (if that's what you're using) or an external DSP/Speaker management system (like the Behringer Ultradrive or a DBX DriveRack).
If you habe any further questions, don't hesitate to ask, I or the rest of the comunity will try our best to answer...
I hope this helps :)
I have another question. Why have almost all manufacturers abandoned any other designs other than bass reflex or bandpass? because the drivers have already become too powerful to spend the mass and volume of acoustics on design?
I've been doing end fire cardioid almost always if I have two subs available... it gives even sound across audience and cleans up the stage and has very low setup and processing requirements.
To do something more fancy one'd need thee or more subs and more processing :)
I hate spaced pair subs that are very common...
Impressive! Question: if you only have 2 sub in a home theater 20’x30x20 (WLH) what would be the response if you put the subs diagonally? That is front right, back left.
You would get some serious power alleys and valleys with them being spread so far apart.
How about indoor backed up against the wall 2 sub left right 20 feet apart? Most DJs like me have to put the speakers near the wall...
I'm a bit of a dinosaur and have not mixed sound since the Mackie analog boards were popular. Our pastor found out I used to do this and asked if I could help figure out how to add more bottom end to their system. They have a JBL powered subwoofer, i believe its the PRX series either a 15 or 18. The sound booth is situated on the side of the auditorium which I know is far from optimal and the sub sits next to it. After watching your video my question is can one sub work ? I now know we need to move it to the front center but I don"t know if we can rig this to the ceiling. Our only other option would be on the stage center but from what I'm understanding this is not good? The room is not huge and its wider than it is long.
If you're not able to put it center, put it in front of your stage off to one side. Like you said, optimal would be to fly it center. Even better would be to fly two of them in the center and space them 5ft apart of so so you can narrow the coverage.
@@MichaelCurtisAudio Thanks Michael!
What is the best space to a hard wall for a 2 Subwoofer Cardiod - inverted gradient stack? If they are both away from the wall, the best space is as close as possible. But How is the best space, if one is facing to the wall?
If working with rear ported bass reflex, how would you calculate using an inline gradient or a stacked gradient deployment? Generally, how would rear ported subs react as a whole in any configuration?
Can you do a video about DJ Line array systems like the Bose L1 pro 16. Since the subs are part of the line array I usually put one on each side of my DJ booth which is only about 6-8 long. By doing this am I causing alleys on the dance floor? Should I put the two speakers in front of my close together and have them slanted out or will the high end speakers in the system cancel themselves out because they are too close?
In your case I would still put the two columns separate. I'd probably toe your speakers outward some more since the high frequency coverage is very wide. But I also understand you want as much of the energy to go to the dance floor and not other places in the room.
With your subs about 6-8ft apart you are getting some narrowing of the low end coverage, for sure.
Michael is it ok to run a cluster for FOH in a small venue from one side of the stage
If the stage isn't too wide I'd say it's just fine. If you have a wide stage the low end can feel "lopsided" from an imaging standpoint. I'd test it out - try a LR vs a side stack and see which of the tradeoffs you would rather live with.
Ok will do
Michael is ok to run sub on one side on a stage in a real small church
Thanks a lot Michael.
I wanna know if its possible to have two different xover points for the rear sub and the front facing sub
Man I Love your content. Just wondering do you have a video for B22 subwoofer Cardiod setup? Thank you God bless
Thank you! Is the B22 a specific model or type of cardioid setup?
@@MichaelCurtisAudio we have a D&B B22 Bandpass subs at church and I'm planning setup like a cardiod setup. Is it possible?
Hey Michael, do you know a brand called wharfedale pro? Any chance you could do a video or review on thier delta range of pro speakers?
In the inline gradient cardioid setup, why is the speaker closer to the stage being delayed, and not the one closer to the audience? Is this because the intention is to have the wavefronts sum (and cancel, being out of phase) at the stage position?
Great question! This video goes in more depth on that - ruclips.net/video/e90v1NVT7bQ/видео.html
You got the first half of the question right. This recipe creates cancellation in the back, but we do also get summation in the front. The rear sub arrives a half wavelength late at the sub's center frequency (this is dependent on your spacing), but is now polarity inverted, so it flips the comb filter upside-down and has summation throughout the sub range. You just have to be careful and not space them too far apart or the comb filter will bandpass your subs too much. Farther spacing is for systems with lower crossover frequencies.
Hey Michael, thanks as always! For the halfwave spaced setup: When you say "up to" the crossover frequency, do you mean by distance or frequency? For example, if my crossover is 80hz, is my spaced limit 7ft? Or can i space them more @ 11ft to boost 50hz?
Why you don’t consider an ‘end fire’ setup in a situation like that? That’s by far the best config in terms of efficiency, phase response and alignment in the front while allows you to have some rejection in the rear.
End fire is definitely a great option to have in the toolbag. I actually deployed an endfire array just yesterday.
The reason why I didn't include it here is that I rarely have the real estate necessary to do ground stacked end-fire arrays, so have to default to more compact solutions like gradient stack. Gradient configurations also have a more stable coverage pattern over frequency when compared to end fire.
the thing I wonder the most about sub setups is how much max spl for most of audience is lost for each setup compared to just putting the 2 together to get that full 6db increase because a lot of times I need to get The most max spl out of my RCF Dual 18”’s because I don’t have enough
It will be amazing if u can have guide for small room listening room for multisubs
I have watched this video a bunch of times. it is gold , thank you!
I had a question. for the dual center, side by side Omni pattern and the half wavelength setups, do the same principles apply at a higher Crossover frequency. for example would this still apply for a 180hz cross over with FOH tops on each side of the room/stage and the subs in the middle? and would that cross over point (180hz) be too harsh? the cross over point is common on a popular Column array vendor kit. the cross over point is set at factory and can't be adjusted, but wonder if separating the tops from the subs and setting them up side by side would help focus the low end on the dance floor. thanks in advance. I've been going through your other videos, very cool stuff
Yes, same principles would apply! But do keep in mind that we want the same tonality everywhere. So, you could focus the sub on the dance floor, but you don't want folks standing away from the dance floor to only hear top end, then hear a big tonality change when they walk on the floor.
@@MichaelCurtisAudio thank you, that make sense.
Can you run the simulation again but add the bass that is coming from the stage, and see how that sound affects the alleys and valleys?
Are you talking about the bass guitar cab or the reflection of the subs off the rear wall?
@@MichaelCurtisAudio Bass amp on stage
Is there more detailed demonstration anywhere explaining cancellation in this setup?
Cardioid Subs Explained For Normal Audio People - ruclips.net/video/EgHK1s7SzIE/видео.html
Cardioid Sub Workshop | Inline Gradient - ruclips.net/video/e90v1NVT7bQ/видео.html
OK thanks, I'll take the time to watch that with thought.
I guess I have had few misconceptions; firstly I thought that back-facing a sub reverses the phase, but it's not dipole speaker... Then I thought delay+distance are mandated by summation frequency wanted, but actually delay compensates the distance. I guess that distance is mandated by summation frequency then?
Good stuff and well explained.
love the videos
I wish you could do some for domestic home Cinema subwoofer positions and EQ
For now I'm focusing on live setups, but a lot of these principles still transfer. I'd check out Jesco Lohan at Acoustics Insider for small room acoustics and speaker setups.
@@MichaelCurtisAudio I had hoped that was the case so its good to know the videos will translate to a domestic setup 😀
Could you do an analysis over what the coverage be if subwoofers were up against a brick wall? Also, what would the response be if the subs were about 15 or 20 feet out in front of a brick wall?
Great questions, John. You can think of any hard reflective surface like a brick wall like an audio mirror. Any sound going into it will be reflected back at the same angle of incidence.
Given that, it's usually best to have your subs as close as possible to boundaries or at least 10ft/3m away so you can avoid speaker boundary interference (cancellations that happen at the speaker due to the reflections).
How does inverted gradient side by side perform in comparison to stacked?
In relation to the inverted gradient stack center setup, how do you find the distance between the drivers when you can’t see the drivers, like in the QSC 212? If the two subs are identical, it just the depth of one sub?
Yes, it'd be the depth of one sub.
What if the Singer is in front of the PA sistem ? Any Ideeas on how to set up The PA sistem ?
How’d you get the playlist pill button in your description, if you don’t mind me asking? Just text link and youtube converts it? Thanks
I copied and pasted it from another youtube channel that has the pill and I keep it in a code block in Notion where I type out my RUclips descriptions.
@@MichaelCurtisAudio Nice. Thanks for the tip and explanation of cardioid subs.
I'm not able to center cluster my two QSC KS118's (cardioid) because I have a video DJ booth. Is it OK if I put them on one side? My entire setup is no wider than 12 feet. Also, is it OK to cover the subs with a cloth covering to help conceal them?
You are amazing I really appreciate all that you put out there. I'm trying to set up a inverted gradient stack. If your soundboard/subs don't have a built in delay, what kind of hardware would you use if software isn't an option?
Thank you for the kind words, Jefferey!
I'd check out the AHM-16 from Allen & Heath.
Thanks for the organized information. Can you clarify how dual 18 subs play into this?
What happens when they are side by side giving you four 18s somewhat evenly spaced (space between speakers in the box and end to end spacing between boxes).
Where do you measure from when doing a half wavelength setup?
Thanks in advance!
Hey, Michael. The big difference with the dual 18" cabs vs single 18" is that they're twice as wide, therefore creating a wider baffle and line length. So, placing two dual 18" cabs next to each other would have roughly the same width as four single 18" cabs. The same principles apply - a long line of speakers creates a narrower pattern.
As far as measuring the half wavelength, as long as you choose the same reference point on each enclosure you'll be in good shape. It could be the center of the box, the center of one of the woofers, or the sides of the enclosure, just as long as the boxes are identical and you measure from a consistent point.
@@MichaelCurtisAudio Great information. You have a new subscriber. 👍 Thank you!
Let's say there is no stage and the band is playing on a concrete pad. Is it still best to do a center sub array if they don't mind seeing a sub or two in the center or is LR the best way to go to avoid looking awkward?
Hi Michael! How do I align phase of side tops with center sub cluster? Should I just put measuring mic in the center of venue and align tops one by one?
Great tutorial thank you, i would like to ask, lately djs and performers prefer to have subs on stage for monitoring purposes, how does having subs on stage affect the cardiod behaviour setup of the FOH subs?
As long as there's no other boundaries close to the subs besides the stage floor I don't see a problem with it.
Thank you so much for your videos! Is there a way in this software that you use, or can you recommend other software, for plotting subwoofer effectiveness in the way that you do here but for inside environments? I.e. the addition of walls and how the reflection from them might cause another dimension of phase cancellation. Thanks again!!
There's the full version of EASE, but it's pretty expensive.
If I set my subs center either side by side or stacked and the stage is tall (about 5’) and has a brick wall holding up the stage, how does the hard surface behind the subs affect the sound?
Hi Michael! So...if the subs are placed up to one half the wavelength of the crossover point (I'm using 80 Hz), you're still able to avoid power alleys and valleys? I'm I getting that correct?
nice clip man! Tx! Looking to aply this info in my mobile Dj setup. tx!
Thank you Brother, very helpful and great information, keep it up
So I plan on running a half wavelength crossover @100hz.. dual ls801p and ef500p yorkvilles on sticks .. I plan on using your tuning methods, but most of your videos you talk about taking measurements on axis with the mains. I'm little confused as what to do when it comes time to measure the subs. Do I turn off the opposing main and lower the sub outputs -6db like in the attaway video.. But that was also a L/R setup with no coupling, so I'm unsure.
Great question! If my subs are on the ground I usually end up setting the level of my subs about 50-75% of the way back in the audience. Then I time align my subs on-axis with the mains (center sub or LR setup) 75% of the way back in the audience plane.
Hello Michael! Can I put inverted stacked subs pattern horizontal? I meant two subs on the floor, one of them facing to the front and one to the back. Thanks!
Absolutely, but the directionality of the sub will change. If you draw a line from the center of the rear woofer to the front woofer, that will be the direction of the wavefront, so it'll basically shift off axis 45° or so.
Mike, Need to know what program/app you might recommend in place of MAPP 3D that will allow you to insert speaker parameters to develop a similar map. I downloaded the program it worked great, but unable to use the available speakers for the small venue I was in.
I would love to be able to generate a map of how things are right now, and see how it would look after moving the speaker placements and angles.
I'd check out EASE Focus 3 by AFMG.
@@MichaelCurtisAudio Thanks, I actually downloaded it and trying to work through it. Unfortunately I tried downloading the Data direct from JBL, but Ease is saying the file with the speaker parameters is incompatible.
I may end up doing it all manually. Already took space measurements, and using Pink noise have dB levels from 10 Points as well as images of the frequency spectrum from those 10 points.
So while I may not see the exact changes by trying to move things around I can see issues in the current setup.
Hi Michael, great video, just one quick question. I am a mobile DJ, do a lot of school dances, large gyms, I bring 2 Alto 18" subs, I used to put them LR but now I put them together on one side and I have 2 Alto 15" main speakers on top of them. Sound difference from when they were LR of my DJ table is way better. My question is since the students are usually right on top of my table asking for requests, i really cannot set them up cardioid so is this the best set up using the 2 18" subs and 2 15" mains, or should I consider some other arrangement for large gyms? Thanks for the info, I am a lifetime subscriber...
Question I have two rcf hd32's and two rcf 702's which i place in front of the stage Thinking of purchasing another 702 sub is it best to position a sub under the hd32 tops and a sub in the middle:
15 "subs are to big to carry
If I put 4 single 18" subwoofers in the center at a distance of 1.5 m or 2 m between them, will they connect?
You needed 1.9ms delay on the stacked iso 2.17ms. Outcome sim looked good so it is not that critical?
I'm a little confused by your question?
Help a newbie here. Currently I have my tops and subs and an analog mixer, primarily for dj type use. What equipment can I start with that has the processing power to add the appropriate delays for a cardioid setup? I'm not totally clear on if I'd need a fancy (expensive) digital mixer or what....
I'd check out the t.racks DSP 408 from Thomann - www.thomannmusic.com/the_t.racks_dsp_408.htm
I personally own one and it has a few quirks, but overall an sturdy and affordable unit.
@@MichaelCurtisAudio Thank you sir! I made the mistake of going to the store and seeing the new DM3.... so tempting. Lol
Very nice video. Still need one thing though :). In your very nice sims. The rear wall is none existing (looks mostly like free space). But in most cases there will only be something like 1-3 meters from rear wall to subs. This must have a massive effect as these could also cancel out some wavelengths?
Great point, Philip! Yes, in the "real world" your acoustic environment will have a massive effect on your low end. I should have mentioned that as a caveat, but my intention with this video was start with the "building blocks" of these setups, then throw them into other scenarios/limitations in later videos.
I definitely should have mentioned as well that hard stage fronts are a no-go when using cardioid setups in front of them.
@@MichaelCurtisAudio Interesting! can you give a short explanation why a cardioid setup infront of a wall/hard stage front is a no-go?
is it because the cancellation "mirrors" to the front and messes with my summed signal?
My first thought was that it will improve the sound because of reduced reflections...
thank you in advance!
@@mongotoffelLP You can think of any hard boundary near a speaker creating a "mirror image" reflection at the angle of incidence of the original wave bouncing off that surface. With cardioid, even though you're getting less energy going rearward, the reflection messes with the specific parameters needed to create that rear cancellation. The energy bouncing off the back wall behind it adds more energy at a different time and negates some of the cancellation effects.
@@MichaelCurtisAudio Great! I look very much forwards to seeing the next episode :) I have a lot of truble with cancelation from walls.
This is fantastic! For your personal preference doing smaller shows (400-600 people outdoors) what is normally your go-to setup out of these 6?
Thanks, Evan! I'd say it would probably be the center side-by-side setup. With just two subs having them as closely coupled as possible gets the maximum possible SPL out of the rig. It also gives the widest coverage pattern, which is often needed in outdoor setups.
If the stage doesn't have a hard front and the subs I have are efficient (not needing to drive them hard to get the desired SPL), then I'll do an inline gradient seutp.
Where would be the best placement for one sub inside a bar with cement walls ? Having trouble getting my sound to rumble
I'd try directly in front of center stage on the ground, or even better flown directly in front of center stage.
Again, great video. Love using the cardioid setup especially indoor. But. Does this consider ground coupling effect or is it for a system that’s flown?
In this model I didn't have the floor "turned on" as a boundary to have in the predictions. However, you'll still see similar results both with a flown and groundstacked inline cardioid setup.
Super helpful video Michael! But I had a question. I'm working with four subwoofers now, a dual 18 and two 18 inch single subs. I've been placing them in the middle at my events, will it have a similar effect to the two subs being coupled in the middle? I would love some advice about how to place these things for maximum output to the crowd! :)
thx for this very nice explanation!
Hey Michael one thing I cannot wrap my head around. For example, if the stacked center (omni) is generating around -30 db at 130ft on axis, how come the inline gradient setup is able to generate around -24db at the same position. Both of this cases would be in maximum summation at that position (Right?). I understand how cancelation works to 'direct' the sound and one may think that 'energy' is conserved, so if you have no energy out in the back, a natural conclusion would be there will be twice as much going to the front. But I think that this is not correct. For example, if you consider the extreme case of putting both subs in the same position but with 180deg phase difference, that would result in complete cancelation, in other words zero acoustical energy. I hope it makes sense, I will keep thinking about it...
Hey, Diego. Very keen eye and insightful question! You've actually caught an error of mine. In the very first setup, with the two stacked center subs I actually forgot to add the second sub "on top of" the first in the 2D software. Even though it would still look the same before the prediction, having two subs would definitely affect the SPL measurement.
Given that, you saw a -6dB drop in the first example compared to the others. -6dB is the same as half as much level, which is the same as 1 sub vs 2. Great catch!
Long story short, if I had done the first prediction correctly you would have seen the same SPL level at 130ft on-axis.
@@MichaelCurtisAudio Right, it makes sense now, thanks again!
Great Sub stuff!
Thank you!
When using "half wavelength crossover center", do you measure from the center of the speaker or is it the length between the cabinets
Center of the woofer from one sub to another
Hello, Michael! I have a strange situation: when I use aux fed subs, I have poor/low volume from my subs . This happens when kick drum is playing-subs are peaking but the sound is low. But when I play music from laptop, subs work loud and much better! Could you please help with your advice? What could it be? Thank you so much! Victor.
I have 2 JBL VRX918SP, can I achieve this inline gradient with a DBX driverack PA+ ?
Thanks Michael - Can you do inverted gradient side by side? Or must it stack?
You can do it side by side, but it'll change the directionality of the array. If you draw a straight line from the center of the woofer of the rear sub to the center of the woofer of the front sub that's the direction the sound will move.
How would you go about placing two subs in a very wide room? If placed as a center cluster the throw will be narrower. So will it drop off at the sides?
Placing both subs together in the center will actually get you the widest pattern, not the most narrow.
@@MichaelCurtisAudio thanks!😊👍
i recently did an outdoor show. Audience area is size of a football field. I have two dual 18. I put them together touching. had a terrible valley. it was like you turned them off. it was narrow. i started to move them apart and kept checking it. the valley just got wider and wider. it was just dead. we usually do the left right sitch, and have that valley, but not as bad as with them pushed together. my setup did not match these diagrams at all. PS I was right in front of a concrete stage. what gives?
It sounds like to me one of your subs had a polarity inversion somewhere in the chain. They were "fighting" eachother when they were close together because you essentially had a copy of the sound wave coming from the same point in space, but inverted, therefore the sound from your subs was in a silent stalemate.
I was thinking that. They were purchased used. Who knows if some knuckle head "fixed"them at some point in time and reversed the wires. I know this because i had another set and that was an issue. Ill check all my wiring. Doing the same place this weekend again. Thanks for the reply. I really enjoy your videos. I run passive gear. So i don't have fancy built in polarity switches. Lol i guess the polarity built in to x32 would work. When measuring side to side placement...where do you measure from? Ctr to ctr? Outer edge? Where do you get the 5.6 feet?
Can you build a dual 18 with a third facing rear?
Two questions:
- If you stack subs, is there any positive or negative impact (like more pressure in the chest, ... of the audience)? You did do a 2x2 monostack in your other video.
- What if you do angle sub arrays/stacks towards a center point in the audience? :) I often see that in small clubs with L/R stacks.
Thank you! :)
If you stack the subs you will slightly narrow the vertical coverage pattern, which could focus the low frequencies a bit more towards your audience. This affect is much greater with a larger stack of flown subs.
Angling the subs if you're not doing a cardioid setup or working with a sub with built in cardioid directionality will not change the energy in the center. Low frequencies radiate out omnidirectionally from subs.
Love the content. The visuals are helpful and I probably need to brush up on my math. I'm in a room similar to your drawings. Our church meets in a 60'X90' room. We have two Subs and four k12.2. How would you place these for best coverage? Any thoughts on drive-racks?
I'd check out these videos for insight on best speaker coverage placement. Long story short, divide the audience in half and have each K12.2 fire down the middle of its own zone. Fly the speakers if you can. If not, get their trim height as high as possible. I'd do two flown center subs, inline gradient cardioid if possible:
ruclips.net/video/OeaMtRvIysM/видео.html
ruclips.net/video/pNkhxnFNUNU/видео.html
And here's some affordable drive systems/DSPS to look at: www.thomannmusic.com/the_tracks_compressors_gates_de-esser.html