Power Amp vs Preamp Distortion in a Valve / Tube Amp - Info & Demo (Marshall Origin, 5150lbx, VC15)
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- Опубликовано: 5 янв 2021
- In this video I explore and demonstrate what happens when cranking a valve amp into power amp distortion! I have decided to use 3 very different amps - the Marshall Origin 20 which I think relies heavily on it's power being distorted for that classic Marshall tone. At the other 2 ends of the spectrum, I have the EVH 5150lbx which has a lot of preamp gain and a Laney VC15 which has no preamp gain at all. Hopefully this will make it clear what power amp distortion actually sounds like and how to achieve it! Please subscribe for more content coming soon.
Disclaimer - Valve amps are very dangerous. Do not mess with them unless you know how to do it safely!
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This is single handedly the best demonstration of gain I have ever seen on youtube.
Thanks so much!
agreed :)
Fully agreed even 2 years later!
how he played guitar while turning the amp knobs at the same time, amazing
This is a damn good demonstration of how those amps open up as you use more master volume, gotta love a Marshall power section pushed.
I recently purchased the Orgin 50, liked the classic tone. This type of amp is not for the beginning guitarist. You need to understand how to dial in Tone. I just put a Power Soak in the mix… it absolutely unleashed her!!! I found the sweet spot running the Master around 7ish….It’s a Beast!!!
Great video and explanation!
The sound I have always been chasing. Great Job Sir.
Wow, this was an amazing demonstration. Thank you for that, this helps a ton on dialing in a tone.
Excellent demostration and explanation that really solidified these theories for me.
great video dan! this makes so much more sense now
Great stuff man! With load boxes at out disposal these days getting power amp distortion is more accessible than ever.
First of all, your playing style and the tones you get out of all these amps are very musical. Just subscribed for this.
Great video. Thanks very much for the time putting this video up!
Well done . Excellent explanations . Very good sound samples as well . This is how tube amps really work .
Thanks for watching! I’m no expert but hopefully most of the info was there 👍
An excellent description and presentation. Thank you.
Just want to say that this video was excellent. Very clear demonstration.
Thank you 👍
Its also helpful to understand the differences between gain and volume controls themselves. Gain controls are always placed on the input of a component and volume controls are always placed output of a component. Only a gain control can distort or overdrive the signal, while volume controls can't alter the signal. Thats why gain and preamp tubes are focused on so much. A volume control just attenuates the signal. When the power tubes distort, its not due to the volume control. More volume can't add more distortion like gain can, it just lets more signal through and that's what makes the power tubes distort.
Knowing the relationship between gain and volume can allow you to get better tones at lower volumes. if you get the exact sound you want on your amp, but its too loud, add a preamp pedal. A preamp pedal will have gain and volume controls that are isolated from the guitar amp. If you add a small amount of gain on the pedal, then just use the volume control to adjust loudness. You'll be able to play at much lower volumes without touching any of the controls on the guitar amp.
Hi Dan, Happy new year and great to see you back on RUclips. Very informative and although I've always known that amps work like this
I've never seen it demonstrated as clearly. Well done with the volume balance, I think it really helps. When you're standing in front of a
100w Marshall and you turn it up your ears tend to compensate for the massive volume and then you're not sure how to compare the sound.
Great video, cheers Ray.
Thank you mate! It was nice to have a break but great to be back to it 👍 I hope you had a good Christmas.
Really glad that it comes across well in the video. It’s something I’ve been interested in doing for my own curious but thought there might be some fellow nerds out there that would find it useful too. Unfortunately, with the current state of things, there isn’t much call for loud amps 😥
@DanLeggatt I feel like I learned something here so thanks for that 👍
Got a question for you. Can an amp like the dsl100 be moded to put a master volume after the power amp so that you can get the goodness of turning up both pre and power sections and then bring down the total volume hitting the speaker for home use? Is that possible or do you just have to get an attenuator for that and place it between amp and cab?
Asking because from what I understood, you said that the master volume drives the power amp? So even of an amp has the master before or after the phase inverter, if you turn the master down , you won't get the power amps potential distortion?
Awesome work Dan, great video!
Thanks Jason 👊
Really good demonstration, thanks a lot!
This is the best explanation ever. Thanks so much.
Glad it was helpful
I loved this amp from the moment I first heard it. Came from classic rock/blues but shifted to metal and this amp don't do that. So I grabbed an EVH 5150, but this will be the next amp. These things are sweet for all people, be it bedroom players or gigging a large venue.
Yep. The people who hate it, are the ones who are expecting something that this amp isn't. I have one and I think it's great. I have another amp if I want to do the high gain stuff, but the acdc type tone, the origin works. ✌️🇦🇺
great and clear explanation on how pre an power amp works together 👍👍
Thanks for watching! Glad it was clear, there is a lot to cover and I am certainly no expert.
That was really informative - thanks for posting!
REALLY well done comparison thank you!
5150 LBX surprised me, it goes from mushy, woody to quite nice!
Great vid, Dan!! I bought a Marshall Origin 50. Absolutely fantastic rock tones!! I'm in love with it!! Keep on rockin'!!!
Thanks man! I bet the 50 sounds killer with bigger transformers and a bit more balls. Must be louuuuud though!
@@DanLeggatt hey Dan, it would be great a video about just getting different sounds from this amp (origin 20 or 50) and the captor: only guitar, amp and captor. I think it's a very common and spread setup in our bedrooms. I refer to clean sound, creamy sound, blues sound, lead tones kind of ac/dc, and so on...
Very informative! My Carvin MTS combo is a high-gain amp (though probably not as gainy as a 5150), and though diming the 'Drive' (gain) knob sounds fine at bedroom levels, I've found that the amp really comes alive when I turn the volume up past '3', which even with the half-power switch flipped down to 50w, is already approaching stage volume. The bass gets bigger and chunkier, and the mids get fatter. My favorite sound though, when I can do it, is with pre- and power-amp gain blended together. The sweet spot seems to be with the volume set between '8' and '9', and 'Drive' knob on '8'. This is with Sovtek 5881 power tubes. It's brown sound all the way, with more than enough compression for metal!
Great video. Clear explanation and demo. I learned a lot.
Glad you enjoyed it!
Happy new years, Dan !!!
Cheers man! 🍺
👍 great video, the audio captured the differences very well
Really glad it came across! Thanks for watching 👍
Excelent job Dan, you are the best!!!
Cheers! Thanks for watching 👍
great sounds bro!!!
Thanks for the video.
Ok, besides the tubes the power amp transformer takes its part in distortion, frequency and so on. A bad transformer is no good to the sound.
Concerning Marshalls my favourite is the JCM800 over the Plexi or the JCM 900.
I like it when your fingerstyle makes the decision over distortion. You hit low, it is low, you hit hard, you get an agressive tone...
That is the secret to good guitar tone with tube amps, my two cents.... :-)
I personally like the Marshalls, the Hiwatts and the Voxes.
Great video!! I enjoyed it very much and it made me to write some notes on the topic...
Love the video!! .I have the origin 20h myself and yeah you just have to crank the master and then it really open up really sweet amp when threat right.
Totally agree! It still seems a bit of a sleeper amp that can be picked up for not much money at all. It’s not bang on a vintage Marshall but does get in the ballpark.
Less than 1/2 way through and subscribed - well done 👍
Much appreciated 👍
Excellent video, thank you very much.
Very informative - thx, man!
Gr8 explain and demo. Tnx!!
Great video and channel. I am intrigued by the Marshall after your demo. I've never owned one but after watching numerous RUclips studio demos I'm liking the Marshall sound. I have 4 Laney amps, two IRT studio 15 watts, an L5T 1 x 12 5 watt and an L20T 2 X 12 20 watt. I'm recently experimenting with pedals in front of the amp but have always used amp Distortion. Home levels dictate mainly preamp distortion but the Fryette Power Station is letting me explore power amp Distortion. It is a whole new world that only the guitarist with no volume constraints gets to experience but desired by all. Low wattage amps are the way. I had a Mesa Mark IV but could only ever use the preamp gain which gets to be just sad in the end. I'd probably be able to use it now if I hadn't sold it now I have the Power Station.
Cheers! I would like to grab an attenuator at some point. The Fryette has some killer features. Would you recommend it?
@@DanLeggatt I would definitely recommend the PS2. The dual channel version seems very interesting and is probably more versatile for a gigging guitarist. I haven't tried that one. The PS2 doesn't colour your sound but retains the pressure you get from a high volume guitar power stage but at any volume, we'll useable volume I mean. I'm sure you know you can attenuate or actually raise the volume output of your amplifier. The PS2 is 50 Watts I believe. I have not tried it with the L20T yet and the L5T is perfect at 5 Watts anyway. I don't like the 1 watt option on the IRT studio and the 15 watt output is a bit loud where it has some character (above 6) The Fryette is like the magical missing link I'd been searching for.
Interesting vid mate!
Cheers dude! Now just need some gigs to get them up to volume outside the house 🤷♂️😂
I learned a lot here. Dammit Dan, you've always got something new to teach me 😆
😂😂 Glad you enjoyed it dude. At least this video hasn’t cost you any money wanting new gear! 🤷♂️
@@DanLeggatt unless you count the 5150 I’ll be collecting from a mutual friend when lockdown lifts 😆 I think it’s fair to blame that on you now
Cool video. Thanks!
Good stuff, educating and well done! You can get the tone "in your head" in many ways :-)
Very true! Thanks for watching 👍
Super interesting. Thanks!
Cheers 👍
That really surprised me on the 5150. I didn't think turning it up would of had that much of an impact on how bright it gets.
You are a star! Thank you!
Thanks for watching 👍
Great video! I have the origin 20h and cab and this helped a lot I now open up that power section gain to taste and use a little black box in fx loop so neighbours don’t kill me and it sounds great! Thanks so much for explaining this!
No worries! Glad it was a helpful video. I love getting into this stuff so I’m glad there are people that actually find my ramblings useful! Thanks for watching 👍
@@DanLeggatt real useful I’ll get a attenuator one day as I don’t think I can really push the power section as the little black box being essentially a volume control between the pre amp and power sections means I have less signal going to power section?
@@chris51484 Yeah absolutely, I would recommend an attenuator to get that juicy power amp stuff going. To be fair I’ve heard good things about the Bugera Power Soak and the Jet City Jettenuator. I think they both come in around £100. Less on the used market 👍
@@DanLeggatt I may have just ordered the bugera.... I need that Juicy power amp stuff!
@@chris51484 Let me know how it works out for you! Just make sure everything is hooked up correctly before turning the amp on 👍
The cool thing about this amp is that you can overdrive the preamp tube to get distortion while still running the EL34's clean. Then you can crank the EL34's up and add their own distortion to the mix.
To sum it up: There are two ECC83 tubes in the preamp section. Each covers 2 gain amplifiers (ECC83=12AX7 tubes have TWO amplification means). So two ECC83s in the preamp section mean 4 amplification stages in the amp within the preamp section. The third ECC83 is literally a means of the power amp. It does not distort (so does not bring more distortion) but is there for the feeding of the power tubes, in this case the two EL34 (in other cases one ECC83 is the phase inverter for 4 power tubes or for 6 or 8 power tubes). For each number of power tubes ONE phase inverter ECC83 is sufficient.
Knowing this it is clear that whenever you have more than ONE power amp tube in the amp you need ONE ECC83/82/81 tube for the phase inverter.
For example: My favourite guitar amp is a VOX AC4C1-12. It has two ECC83 preamp tubes and one EL84 power amp tube. It sounds the same as a VOX AC30 (without Reverb, Tremolo). Why?
The Vox AC30 has THREE ECC83 and 4 EL84. BUT: 2 ECC83 are needed for preamping (like in the AC4), 1 ECC is needed for phase inverting the "more than one" power amp tubes.
An amp with ONE power amp tube DOES NOT NET a phase inverting tube.
Okay
Awesome demo!
Cheers Neil! Hope you had a good Christmas mate 👍Well as good as you could under the circumstances at least!
@@DanLeggatt not too bad for me, chap. I hope yours was alright too.
I actually really think this is one of the best demos I’ve seen for the difference between preamp and power amp distortion. When I was a young lad getting into guitar over 30 years ago there was no reference material like this and it took decades to understand some of this, and that was mainly just through experience, trial and error.
It’s great that a younger generation, thanks to folk like you and channels such as this, will be able to skip all of that searching for answers and tone for years and just get down to the business of playing.
One of my greatest regrets is getting rid of a 70s JMP100 simply because I couldn’t get that cranked tone at low volume. With all of the various attenuators and load boxes available now I could have got that tone at a whisper volume.
@Neil Gregson Thank you mate! To be honest, there is so much incredible material out there I'm just trying find a few 'gaps in the market' to make content on, stuff that's always interested me that isn't well covered. I'm glad this one came across well. Obviously I still love just making the gear demos but mixing in some of this nerdy concept stuff like this is really fun to me, although it doesn't always bring the views.
To be totally truthful, I've really enjoyed the journey of finding all this stuff out first hand, making mistakes and buying the wrong gear. I wonder if youtube stuff, in some way, is depriving people of that a little bit. Half the fun of playing guitar has been working this stuff out. But from another angle, it probably would have saved me a load of cash! Plus there is no way I could produce a video like this without load boxes and the newer tech like you've mentioned. It's all swings and roundabouts!
@@DanLeggatt I’ve thought that very thing myself: would I be a different player if I hadn’t learned all this the hard way/had to spend all this money on amps unfit for my purpose etc.
I still feel even with all this info out there kids will make bad choices or at least choices they’ll regret and years later will work out what they’re really after. Plus there’s so much gear available now! How can they know what will work for them? However I know if I could do it all again with the resources available now, such as your fine content, it’d be a much easier and less expensive ride. 😁
I dread to think how many starving nations I could have fed with the money I’ve spent on gear over the years. 😐
New sub…thanks for the great info!
to me the best place to be is in the spot of the biggest change .
The feel of air & open natural sounds a grit compression that wild control of play / volume .
Pushing that with any boost. & its golden zone .
I don’t think that we can say its tha power tubes . could be + the transformator.
excite the core of it & it ads its feedback & thats tha sound.
could be the Caps that hold tha energy have greater flux & due to its high voltage flow gets some weird artefacts.
Could it be when you play loud you excite the air & it rattles the Tubes & its feedback to it gives the precived bias that you achieved power tube distortion.
Anyway…
A good One!
Keep it up
You hit V1a first setting the overall tone and preamp volume. Then to the lossy tone stack. V1b as recovery. That is the classic setup for most amps.
The best thing is stacking harmonics. So, pushing preamp and then pushing poweramp. That is easier w a MV amp. A thing to remember is that there are boundary effects fr both sections. Pushing preamp section beyond 'nice' harmonics levels creates fizzyness and you lose dynamics. Pushing output valves and you get hard clipping distortion, often rather ugly. The trick is to find the right balance. Thing is, the usually involves more preamp section harmonics than output valves distortion. And it includes the PI, PT and OT as well, all part of the output power section. They all have boundary aspects. So, in short: people overestimate the effect of output valves. They say they prefer it to preamp valve distortion but they are simply mistaken about the causes of the total output section distortion.
Great video 👍another big difference is that the Marshall Origin 20 and the Laney are cathode biased, which mean a softer, spongier type of power amp distortion (like Brian May's Vox amp) but the Peavey is fixed bias, which is a harder type of power amp distortion, i.e. Van Halen, Malmsteen, Angus Young, etc (ironically, that is the true Marshall power amp distortion, the Origin 50 has it)
Very interesting. Thanks for the info 👍
Perfect 🔥🔥
Cheers 👍
My O20 head just arrived about an hour ago! Woo hoo!
Enjoy mate 👍
Sorry, correction to my text a few seconds ago (I was too fast in publishing .... :-) )
To sum it up: There are two ECC83 tubes in the preamp section. Each covers 2 gain amplifiers (ECC83=12AX7 tubes have TWO amplification means). So two ECC83s in the preamp section mean 4 amplification stages in the amp within the preamp section. The third ECC83 is literally a means of the power amp. It does not distort (so does not bring more distortion) but is there for the feeding of the power tubes, in this case the two EL34 (in other cases one ECC83 is the phase inverter for 4 power tubes or for 6 or 8 power tubes). For each number of power tubes ONE phase inverter ECC83 is sufficient.
Knowing this it is clear that whenever you have more than ONE power amp tube in the amp, you need ONE ECC83/82/81 tube for the phase inverter.
For example: My favourite guitar amp is a VOX AC4C1-12. It has two ECC83 preamp tubes and one EL84 power amp tube. It sounds the same as a VOX AC30 (without Reverb, Tremolo). Why?
The Vox AC30 has THREE ECC83 and FOUR EL84. BUT: 2 ECC83 are needed for preamping (like in the AC4), 1 ECC83 is needed for phase inverting of the "more than one" power amp tubes.
An amp with ONE power amp tube DOES NOT NEED a phase inverting tube.
@lino vinn. An amp without a phase inverter is a true class A amp. You can have more than one power tube in a true class A amp but it still would not have a phase inverter. There are many amps these days that falsely claim to be class A but if they have a PI then you know that is actually class AB. It seems a lot of lower powered amps falsely claim to be true class A amps. A vox ac30 or ac15 is class AB. The vox amp you have I believe is true class A. One is not really better than the other but they are different. A class AB amp will have more headroom, power and volume. They may also have a little more sustain but I’ve played true class A amps that sustained great. Class A amps give up power tube distortion at much lower volumes. Which could be good or bad, depending on what you wanna use it for.
Nice job...
Cheers!
Thank you
You are welcome. Thanks for checking it out 👍
I like the Origen series. The controls react exactly as i want. Small incremental changes..
The output transformer pushed all the way also adds saturation from it being maxed out. My Marshall Superleads have a strong midrange when this happens....I don't like it personally because the dynamics of attack are lost in too much compression....and the 130 decibels of sound pressure are at ear damaging levels!!! I have post phase master volume 's added to them all which sound great when dialed in to let the power tubes add their magic.
Great vid Dan! So would you say, to get creamier, overdriven tones, one would rather use a boost pedal to drive the amp? I thinking more along the lines of a Mike Oldfield, and in a lot of cases 80’s lead tones.
I think you can do it in a number of ways. There is so many good pedals out there, you could even rely on a pedal entirely for the tone into the amp set clean. I really like the Friedman Dirty Shirley pedal.
If you wanted to boost the amp already driving to push it over the edge, my favourite boost is the TC Spark. Really tweakable and really cheap.
The terminal stage does not overload the signal. The volume control restricts the signal of the preamp, not the amplifier. Experiment with the ppimv mode, which restricts the signal after the phase inverter. The lamps of the terminal stage slightly distort the signal with a strong amplitude, practically without affecting the overload level.
Yep, that was good \m/ sadly not many of us are in situations that allow us to get our masters up beyond 2 or 3 :( I’ve had a quite a few amps, some that were just too loud to appreciate without attenuation or ear plugs. Just got a Friedman jr and it kicks, but once again... it needs to be up a bit. All my Marshalls from small to big have to have the masters up past 3:00 before they sound right to me - then they start properly crunching.
Hey Dan, that's a very nice video about power and preamp distortion. I think the first one doesn't get enough attention these days. Very cool tone on your Origin there, especially in the intro! I didn't think it'd be capable of such a nice and juicy classic crunch. What pickup were you using in the bridge?
At the time I think it was a Tonerider Birmingham 👍
@@DanLeggatt thanks a lot, got to check it out!
Great video!
Great riffs too! Are they yours?
The 5150 sounded a bit nasaly to me compared to the other two amps.
Cheers! Anything I play in videos is normally off the cuff, often inspired by something else but my own version so the RUclips copyright police don’t come after me 🤣
There is a reason push pull valves are set to around 70% max dissipation bias. Push those valves and they get nasty. The output section before the valves is where the juice is.
A lot of Plexi/JTM/JCM sound comes from stacking preamp sections. And all modern gain sounds are derived from that.
I think even the earliest JTM45 had the Fender Bassman cathode follower, then tweaked the caps and resistors for desired high volume performance.
Is that Oh Hiroshima I hear ?? Thanks for the vid! I have an ORI50H coming as my first tube amp!
I don’t think so, I’ve never actually heard them before. Was it one of the riffs I played?
@@DanLeggatt i believe its the song in the background when youre going over the signal chain inside the amp! I could be wrong sorry
It’s just a little original track I put together a while ago to go under videos. It’s been on a few now. I’ve had a few comments about it so I might get round to uploading it at some point 👍 Good ear though, it could very well sound similar to something they’ve done.
Turning the volume up on any amp will completely change the way the speakers move and distort. I think this might have more of an effect than the power tubes. Good video!
That and the Fletcher Munson curve which increases low frequencies at higher volumes
Both surely contribute to the sound. A greenback 25 speaker will contribute more speaker distortion than a 100 watt Celestion with a plexi. But if you put a reactive or passive load after the power amp you will hear the difference
Great video, I just came across it. What are the preamp tubes are you using in the Origin 20?
Just stock as far as I know
Speaking "headroom"...you might double check some of the framing, on your shots😁. (not an insult, just bust'n yer chops...love your vids)
Just a quick observation on the layout of the pre and power amp on the Origin.
Sometimes when discussing these sections, people speak about them in relation to the gain and master volume pots.
This depends on whether you consider V3 as part of the pre amp pr the power amp. The master volume is located before V3, as it is in master volume JMPs and JCMs.
However, to me at least, V3 is an essential part of the gain structure, and is why the gain increases when this is turned up.
The power valves aren't getting hit very hard or even much at all unless this is all the way up, allowing the full signal from V2 into V3 to be phase split.
The pre phase invertee(/V3 master volume, again imo, is only really another preamp gain.
Which is why I installed a post phase inverter master volume.
Stemming the signal just before V4 and V5. As it should. Imo. :-)
Great tones though.
I definitely agree that they missed a trick not having the master post phase inverter. I also think they wasted v2 on the fx loop. I think they should have incorporated into the core preamp or boost stage and given a larger gain range earlier in the preamp. I reckon it would have appealed to a wider market.
i think the post PI mv are great in bigger amps like a 50/100w b i think Marshall got things right w the Origen 20. To me it has the right interaction f small/medium stage duty.
i also think that people overestimate the output valves influence on the sound overall, 6l6 or el34. It is usually transformers breaking up w or without PI. Although personally i like el84s pushed if i want output valve distortion.
Thanks, some more advice, if your pushing the amp with pedals make use of the effects loop, it’ll make it easier to tame the harshness of the preamp.
Cool. What do you use in the loop of yours?
@@DanLeggatt I’m doing two things with it so far... running an OD in front and delay/reverb in the loop... what’s really interesting is running preamp blocks directly into the loop power amp... All with a helix, the power amp is actually very warm... I can also use a volume pedal in the loop to get the tone of the amp at a much lower volume, it doesn’t seem to effect the gain/master tone much... I need to play with that more, but most of the breakup in the amp appears to be only in the preamp not the power tubes, I could be wrong though and need to test more, but I’m thinking you can get all the tone and lower the volume in the return.... it’s a very cool amp that seems to do almost everything well... but being able to revoice the power amp with the preamp models has made me love it... the power amp/cab is pretty transparent so it works well... I’m surprised by that...
@@DanLeggatt I’d bet it might be easy to mod the effects loop with a single potentiometer to adjust the volume level after the preamp... the master is actually part of the preamp as it has no effect on volume after the signal comes back into the FX loop return... it’s straight into the power tubes from there...
@@DanLeggatt I’m happy finding this because I was thinking the amp was a little brittle due to the smallish output transformer... that’s not the case at all... it’s the preamp only that’s a little harsh... finding this made me happy because I’m able to dial in any tone easily... had the transformer been the problem that wouldn’t have been the case...
Very cool video! So listening to early Jimi and EVH tones on VH1, that overdriven, crackly/crumbling speaker sound was that pre or power amp distortion? I always loved that sound in a hard driven amp especially when it also has clarity to it aka brown sound. So VH1, is that all power amp distortion I'm hearing in what I just described??
A mixture of the 2 really. Those amps they were using just had a volume which would in turn distort the preamp and power amp the louder they were turned up.
If I went into the return with a clean Preamp, would I go directly into the power tubes? Being able to use only Master and Presence, right? ( Marshall Origin 20 )
Great video & demo.
Apologies if you’ve already covered it, but what are your thoughts on volume pots in the fx loop, vs power soaks between the head & cab? If I understand correctly, the volume pot allows you to drive the preamp, whereas the soak allows you to drive pre & power?
Given your demo shows how the power amp clearly shapes the tone as well, would it be fair to say a soak gives a better approximation of a valve amp on full chat, but at manageable volumes?
Cheers! That’s an interesting discussion to be honest. For certain amps it can be effective using one of those volume box in the loop. It depends on what you are trying to achieve and where the FX loop is placed in the circuit.
For example using it on an amp like this would basically replace the master volume. You wouldn’t be hitting the phase inverter or power amp any harder. You may get a bit more juice out of the amp.
For an amp like the Fender Hot Rod deluxe those volume boxes work great because the amp doesn’t have a master volume.
I think for an amp like this an attenuator would be a much better option. Obviously this amp has some degree of power level attenuation on the switch but even low isn’t bedroom volume.
This whole thing would actually make quite an interesting video now I think about it 🤔
@@DanLeggatt Thanks for the reply.
I’d happily watch one of your videos on this! 😉
I have an ‘original’ JCM900 4100, and I’ve played around with a volume pot in the loop (Carl’s Custom Guitars) and although it improved things, it never quite did it for me. I seem to recall the Marshall Power Brake uses a fan to cool a heatsink, which I found distracting, and ironically noisy (especially when trying to record). I’ve been considering the Bugera PS1 Power Soak, as apart from being much cheaper than the Marshall, it also acts as a DI for recording.
I know this is another subject altogether, but functionality-wise this is an attractive prospect - potentially a kind of ‘best of both worlds’.
But, my cynical side thinks it’s too good to be true...
@@CaptainBlackadder75 The bugera ps1 is a passive load box. That's why it is so much cheaper than the UA Ox box and similar reactive attenuators.
Hello, my power tube retainers won’t screw in once I took them off, is that bad, any way to fix?
it wav different size frequency distorting is why the note sound like a bell passing
I had an Origin 20 and I wonder if it was a lemon, because if I had, tilt, treble and presence like this, it would sound unbearably trebly.
What I would like to know, Randy Rhoads for instance, used a Marshall 1959. It just so happens to not have a master volume or perhaps a preamp volume? What does that particular amp push more, the preamp tubes or the poweramp tubes when the only volume is turned up? Are you saying that because there's only one volume, it essentially pushes both preamp and poweramp and is this why Marshall snobs hate master volume amps? How could this scenario be used in a modern Marshall like a DSL40cr?
Well it is really a good and very usefull vidéo ! thanks a lot for doing it. But which kind of pédale attenuator would you suggest to push the master volume and reach this specific sound without denaturing the original sound ? And without blowing your head off ^^ off course :) thanks for answering :)
Definitely go for a proper attenuator that goes between the head and speaker cabinet. Luckily there are some on the market now that aren’t that expensive. Such as the Jet City Jettenuator, Bugera Power soak or the similar Harley Benton model 👍
@@DanLeggatt Thank you for your quick answer (not as mine...) I'll try the HB to see what i can get. I've got a 50h Origin Marshall as well. It neads time to learn how to found all the sounds that he can propose. Thanks for your channel and videos Dan. And excuse my english, i'm french ^^
@@bloodypura5385 Merci d'avoir regardé ma vidéo 👍
So what about an amp that has a volume knob, a master, and a gain knob?
Hey man, great explanation! I have a Randall RH150 G3 150W Tube/Mosfet head unit and it keeps blowing the 12AT7EH pre amp valve, I suspect its a dodgy power convertor (It's an American Head unit with a US-UK power convertor which has been dropped a few times and is held together with gaffer tape!) so i've ordered a newer updated version power convertor from Gear4music which should be here in a day or two.
Do you know if my amp's clean channel will work without the pre amp tube being in it as I intend to play Bass through the Randall head as it has really good bottom end and i'm a cheapskate and don't wanna buy a Bass head unless I absolutely need to!
Thanks in advance dude, Subscribed :)
Depends totally on the circuit. If the tube is in the path for the clean channel then no.
do you think the Marshall origin would be good to run a synergy system through the fx loop? mainly Ising the origin as a power amp?
Tough to say but I would imagine so. The Marshall power amp feels a little ‘squishy’ for lack of a better word. I’d imagine it would work great for the Synergy Marshall and vox inspired modules but might not be idea for super tight high gain.
Most of what people think as Power tube distortion is actually phase inverter
distortion power tubes don't actually distort much if at all.
I’ve learned through more tests and research that the PI is far more a factor in the tone than I thought.
@@DanLeggatt interesting! I was watching a repair video on the Blues Junior in my quest to get it to sound better with overdrive (amp or pedals) and someone mentioned changing the phase inverter tube to smooth out the gain. Not sure what they specifically recommended.
Nice video by the way!
I'm sorry brother but you are very wrong about the way your Marshall origin 20 works. You were correct about the first valve in the chain but the second valve in the chain does not have anything to do with your effects Loop, the effects Loop is actually driven by an operational amplifier ,IE solid-state. The second valve is just two more gain stages meaning the preamp has four total gain stages. The signal chain is in this order: V1a/gain pot/V1b/tone stack/V2a/V2b/operational amplifier(FX Loop)/master volume/phase inverter/ then the power amp tubes. I know this is a long-winded comment my point simply being is that the 2nd 12ax7 does not drive the effects Loop.
Not sure where you are getting your information but my buddy Jason breaks down the full circuit in this video - ruclips.net/video/Q_hiXjOS1Y8/видео.html
17:44 he talks about v2 and it’s use in the circuit.
@@DanLeggatt I'm getting my information from looking inside the amp itself. Unless there's several different versions of this amplifier which I seriously doubt then your buddy is incorrect. Yes it is a valve amp but there are solid-state components when it comes to the effects Loop. There's not a single Marshall amp in the world that only uses one 12ax7 in the preamp. They all use at least two sometimes three. I'm 40 years old and I've been repairing amplifiers since I was 12. Open the amp and look in the back and you will see an operational amplifier on the rear board that the effects Loop is connected to, what do you think that operational amplifier is for??
Great vid Dan! Interesting to hear the different elements of an amp doing their thing, without the whole bleeding from the ears 😂
It'd be cool to hear about why you'd choose an amp with a certain power amp or wattage for a particular sound, gig or session.
Cheers mate 👍 100w full stack for everything obviously 😂 Interesting idea for a future vid, I’ll add it to the list!
Same stuff different day since yngwie to present same tone if you can call it that, nothing changes after malmsteen.
I have never seen such small and toy like transformers like marshall are using these days
They are a bit on the small side but to be fair, this is a 20w head. The transformers are about the same size as in any other 20w and under head or combo I’ve owned. I’d imagine bigger iron would be an improvement but you can’t have it all for this kind of cash.
Why don't you run a clean boosted guitar signal into the Effects Return jack? I can hear a difference as you turn up the Master, but you've already distorted the signal with the Gain control. We all know what coloration the Master can add to the signal, thanks to Marshall's various attempts to do a good Master Volume throughout the JCM800 series - and this amp is not a Post-Phase Inverter Master Volume, so the Master is loading the output of the preamp.
With all due respect, a non master volume old Marshall/Fender is the best representation. No fx loop. No gain drive at all.
Use a Plexi NMV circuit for the Holy Grail sound
No wonder I think my Soldano tone sounds like shit. I live in an apartment and even with a -20dB attenuator I can't comfortably crank the Master volume past 2. RIP.
Why not just add an 11 to all the knobs?
Joe Perkins with a beard
I don't hear any power tube distortion from any of your amps, just the mid tones coming up louder, that's something that power tubes do. You really need a 68 to 71 Marshall to get the power tube distortion, it is far more dynamic then preamp gain.
I’m not an expert but pushing the volume on any amp will cause the power amp / PI to saturate. Saturation is distortion. Those Marshall’s are certainly not the only amps that have power amp distortion. Although I would be interested to hear why you think that’s the case?
@@DanLeggatt it could be the amount of head room on your amp, I would look at the negative feedback resister, and try lowering it on that amp, I put a lower resister and a 1k volume pot to have it adjustable on a Ceriatone yetti kit amp I built, you could dile it down so it would brake up early like a vox amp, or bring it up to a Plexi , one hundred k on 4ohm tap, that will definitely go be you power tube brake up.
That origin is naked oofff
Amps look cooler out of the box. Say it’s not so….
Are guitarists today growing up not knowing that an amp sounds better cranked?
I live situation, I cannot use preamp gain. I just can't control it. I get much better tone by cranking the power and use overdrive and distortion pedals. Much better tone - for live use. That's how Paul Gilbert does it. I saw him live and he gets a fantastic tone. He was using Marshall Plexi's. Much more clearer and not mushy.
He is Russell Crowe
You look a little like Jesus Christ...but the videos are always OK! Well Done!!! :-)))
Thanks... I think 😂
@@DanLeggatt Yeah bro, don't worry!!!
I like totally what you do, cheers from germany!
ALL SOUND pretty annoying. Extra preamp gain has a different distortion profile than power amp distortion. The driver has its own and unless you have all three, you get tizzy gargly tone like you get here.