"Tube Sag" at Any Volume - Compressor in the Effects Loop

[@michaelrichards3168]

Love that you used graphs to explain what is going on instead of buzzwords that describe really subjective sounds. If a picture is worth a thousand words, a graph is worth at least a thousand data points.

[@insanecomicdude]

Thanks! I'm glad you liked it. It was a lot of fun to make.

[@mohitrahaman]

i feel tube sag like "squishy platypusey-procupiney soft toy" thing

[@rebelmastermind2350]

Dude, you deserve to have a statue built in your image at the center of your hometown.

[@TriodesPs111]

lemme give some more info on this, the uploader is right about voltage sag giving compression, but voltage drop changes alot of things in the amp, (the whole "feel" of the amp is affected) the lower plate voltage at the plates of the tubes as a result of the drop in voltage during a high current demanding state will lower each tubes headroom, (so more compression AND distortion) it will also change the distortion characteristics a bit AND it will affect the EQ of each stage slightly. usually less plate voltage = lower headroom, more dist, warmer and gritter sounding, less volume. so its more then just compression. the amount of these affects caused by voltage sag will shift in response to your guitar signal as it affects the current draw demand in the amplifier,(digging in vs playing soft) making the affects of voltage sag very complex and shifting in response to your signal. i build amps and have bin amazed by how much an amp's tone character can change by giving it more (or less) voltage sag by design. just putting a comp pedal in the affects loop doesn't fully replicate the complex and interesting nature of voltage sag. the comp pedal in the FX loop isnt affecting the distortion character or tone character of the tubes. it only some what crudely imatates the compression aspect of voltage sag. no offence to the uploader, i just didnt want peeps to think all voltage sag was is compression. cuz its more then that. =)

[@insanecomicdude]

Thanks for the comment; very well explained. You're absolutely correct. I have thought about trying to build a "sag" pedal that compresses by lowering the headroom on a jfet gain stage or two. I think that would get a lot closer to the real deal, especially on cleaner tones. P. S. I didn't know about the EQ changes. Do you know what causes that? I would think plate resistances and such would stay about the same regardless of plate voltage.

[@TriodesPs111]

​@@insanecomicdude what i was referring to is that when plate volts drop there is a change in tone, mostly in brightness, i should have mentioned that im speaking from personal experience and not really from an exact scientific understanding, but what i have noticed my amps doing as i've messed with sag level in the amp, is more sag makes the amp darker/warmer even can be thicker sounding with more grittiness in the distortion maybe even fuzzy character and "squishier" too from the compression we get. its also worth pointing out that in my findings, it also tends to be on more higher levels of sag that makes me notice the darker/warmer tone, amps with enough sag given to them can get dark and fuzzy in tone. and an amp that has some sag but not alot of it may not have its brightness affected enough to notice it. and of coarse different circuits may respond to sag a little differently, but these affects are what i've noticed from my amp building over the years

[@insanecomicdude]

@@TriodesPs111 what do you do to adjust sag level? A series resistor in the power supply or something with a choke? I don't understand how chokes interact with power tube screens.

[@TriodesPs111]

yeah i put sag resistors in series between the rect and the filter section, i built an amp with the preamp design of the 3rd channel of a EVH 5150III paired with a power supply section and power amp of my own design, i put a rotary in it that lets you select more or less sag by adding in or taking out sag resistors. the resistors are rated for 15 watts but you may want to go with a higher wattage tolerance if you put them in higher watt amps im sure you dont need me to tell you that if you decide to add sag resistors into a tube amp, you shouldnt do it unless you have learned proper tube amp safety and are absolutely confident in your abilities. when i started doing what i do, i wasnt as safe as i could of bin and got a few good shocks. nothing damaging but still as scary as a wife with a gun! ,i took safety very seriously after that.

[@insanecomicdude]

@@TriodesPs111 that sounds awesome. The rotary switch is genius. I built a low wattage SLO clone once and put resistors in that same way (did the math to figure out how big) and it worked great.... For about 30 seconds. I had the brilliant idea to use pin connectors everywhere on my boards and they were extremely unreliable. Never got it working after that. Part of the reason was that it needed a redesign as I used a tone stack that brings down the signal level a bunch and then couldn't get any volume from my power section.

[@charlesjohnston9814]

Damn. That’s one of the best explanations of anything I’ve ever seen on KZbin. 🙌

[@DorGreen1]

That explanation was SPOT ON. I have some background in electronics and understand the basic wave transformations of the signal chain but this REALLY tied everything down.

[@jimgillis8522]

Got a kokko compressor into my Fender Champion and WOW! Is all I can say. It’s mostly a feel thing but adds some “bloom” to notes

[@insanecomicdude]

Yeah! I find that compression after distortion and eq (mostly bass) before distortion really affect the feel.

[@jimgillis8522]

kzbin.infomrLMBd1INuQ?feature=share

[@darwinsaye]

I've used this trick to make solid state amps have a more tubelike response. I'm very aware it's not the same thing as tube sag, but if you have a decent ss amp, this can help tame the sharp transient attack that is characteristic of solid state. (To specify, I'm talking about a solid state amp set to clean or edge of breakup, not high gain. Before anyone jumps in with all the 'Solid state clipping is not the same as tube clipping ... Even vs odd order harmonics ... Symmetrical vs asymmetrical clipping' rants -- I know *all about it*, and I've been using both tube and SS amps for over 40 years).

[@insanecomicdude]

It's really a nice trick. My goto amps these days are some of those little hotone 5w solid state amps and it really can give them a juicier feel. Not to open the solid state distortion can of worms, but it is my understanding that if youre preamp distortion stages are just class-a jfets or similar, the distortion characteristics are basically the same as with tubes (since it has more to do with circuit structure than actual components). Has this been your experience as well?

[@darwinsaye]

@@insanecomicdude I'm not sure what the circuitry is in my old 90's Fender Sidekick, but I think it is (maybe?) likely jfets in the preamp, given the era. I also used to have an 80s Mosfet based Marshall SS amp, which according to the circuitry gurus, is also supposed to emulate the physics of valves very well. Based on my experience with them and various drive pedals I've owned with different clipping circuitry, I would probably have to agree. The Fender sounds very much like a Blackface tone if the drive is kept from clean to low gain. The Marshall actually sounded astonishingly like a Marshall JCM800 (which it was supposed to be a solid state version of) at higher levels of distortion - that amp pretty much threw out the old argument that solid state amps are only good for cleans. It really did an accurate emulation of the Marshall tube distortion tone. Sadly I only really enjoy Marshall clean to edge of breakup tones, and that amp had almost no headroom. The only drive pedal I currently have that I know for certain is jfet based is my Boss OD2, and I can attest that it has a much more tubelike response than something like my Op amp based Rat. So I'd have to agree with the jfet assessment.

[@BreauxBobby]

I agree that the sum of the effect of an amp's tube rectification is more complex than throwing a compressor in front of your amp, but what this guy's saying is spot on. I do believe that a good compressor can achieve the same thing as far as our senses can understand what's happening. I have an Xotic SP compressor and an older Boss CS-2. I can fine-tune the boss to sound pretty close, but the release is what sets a tube rectifier apart from a stomp box compressor. You might have to hunt for a compressor that does this perfectly. The Origin Effects Cali76 Stacked Edition probably comes close. I had a Fender Bassman 100 watt and when we'd play big outdoor shows, I really understood what tube rectification sounds and feels like on high wattage amps. You can hear it easily on a Deluxe Reverb. And to me, it's like leaving your compressor on all the time. I don't think it's as magical as people would like to think it is.

[@chrislenczyk8617]

I finally couldn’t stand the hissing from my compressors which I have a boss CS3 and Sp with a blend. Maybe I was pushing them too much in front. So I put the boss in the fx loop this week which led me here. Amp is Mesa express 5:50. No hissing when placed in loop except a little from the SP(sometimes it’s noisy some days it’s not??) I’ve also got delay and chorus in the loop. I’ll make some proper miced recording this week and see how it mixes. Would like to add another amp for a stereo effect.

[@BreauxBobby]

@@chrislenczyk8617 I had a 5:50 +. What an amp! I had to sell it when I moved to Europe but it was so versatile.

[@go-away-5555]

Just to be clear to anyone else, it shouldn't be in front of the amp, it should be in the effects loop. It's a subtle difference, but more accurate. Basically you want it to be after the pre-amp/distortion section but before your power amp section. A pre-amp doesn't really sag, it's the power amp that does. Otherwise the compressor will be lowering the volume that goes into the pre-amp which will dynamically affect the amount of pre-amp distortion. This is the typical way people use compressor pedals with distortion. It's a subtle difference either way, both sound good, but putting the compressor in the fx loop is truer to the sound of real tube sag than putting it just before the amp entirely.

[@BreauxBobby]

@@go-away-5555 That's good information. I never even thought of this. Thanks!

[@gundrillerman4810]

I came here to learn what sag is, Now I’m ready to graduate Devry Institute of Technology...

[@kennethyates]

Much appreciation, finally a clear explanation without the woo woo guitar freak mumbo jumbo!

[@michaelinglis8516]

I figured this out on my own tonight and lost my shit and wondered if i was the only one lol. The exact tone my compressor sometimes gave me that i loved it always gives me in the loop. Plus the treble booster i built doesnt play well with my compressor so its one or the other. But not now that i have the compressor in the loop. So fucking happy to get to have both now.

[@insanecomicdude]

That's awesome! It's a pretty good sound, for rhythm and lead I think. Depending on what you are going for I guess.

[@dannyrivers3922]

I get it now cause the drawing! Thanks. But the audio from my phone you can't tell much a difference from the compressor on our off as far as that sag. Loud in pick attack, volume drop on notes held.

[@insanecomicdude]

Thanks for watching. Give it a shot with headphones or speakers if you get the chance. It should be easier to hear, then.

[@Dany12156]

For anyone who is reading comments cause Behringer CL9 behaves not like on the video. Normally CL9 is cited like Ibanez CP9 clone where Sustain(CL9) is Threshold , Attack(CL9) is Attack and Leve(CL9) is presumably Level. However, i own Behringer CL9 , which looks exactly like on video, but where same knobs mean different things and it looks like a clone or Maxon CP9 Pro but without led indicator. There, Sustain(CL9) is Gain , Level(CL9) is Ratio of compression and Attack(CL9) is a Threshold. I do not know what is the reason behind this , but in my version of CL9 if i set Sustain on min, there is no sound , it completely blocks signal and Level and Attack sounds exactly like Ratio and Threshold.

[@insanecomicdude]

That is really weird. So are there different versions of this same behringer pedal?

[@영상시청용자기계발부]

you solve my 5 years old question about compressor before or post preamp, you are awesome

[@insanecomicdude]

Thanks! Glad it was helpful! Putting it before a preamp or using different settings can give you a different result. Not better or worse, just totally different. I'm still learning all the things you can do.

[@영상시청용자기계발부]

LiveOVErdrive thanks, can i ask question? Polyphia tim henson's tone is post preamp compressor i think. It is right..? I think it is not before the preamp

[@insanecomicdude]

@@영상시청용자기계발부 I don't know for sure. His tone is pretty tight and smooth. I would guess if he uses a compressor it is before the preamp. More likely though he's using an overdrive pedal as a "boost" in front of the preamp, which is to say turning the gain all the way down, turning the volume/level all the way up, and adjusting the tone to taste. Then you set your preamp gain pretty low because the signal coming in from the pedal is already very high. This is really popular in modern "tight" metal tones. Basically what it does is reduce bass before the distortion, which keeps the distorted signal from getting flubby. Often people will then add bass back in AFTER the distortion/preamp with a graphic EQ, but for polyphia tone I think you would skip this. That guitar tone is very midrange-focused, without a lot of bass.

[@insanecomicdude]

@@영상시청용자기계발부 forgot to mention he probably has a very fast gate after his preamp as well, to give it that very snappy, percussive tone. There IS a little punch there too so it is possible he is doing this post-preamp-compression thing too. I'd start with the gate tho.

[@allboutthemojo]

@@insanecomicdude i have a dsl 20 Marshall tube amp. It is too loud for my home so I cannot experience that great cranked tone. The set up you explained here, applies to tube amps as well? Should I just run all the pedals through the effects loop? Appreciate your input.

[@leiferickson3183]

Great description and demonstration! Awesome content.

[@insanecomicdude]

Thanks! Glad you liked it.

[@mountainpeakcloud8442]

Thank you for putting the demo at the beginning of the video, because my brain shut off once the science started, lol. Not your fault, just how my brain is wired.

[@vikingsofvintageaudio7470]

Fantastic explanation, do this more often!

[@insanecomicdude]

Thanks! I'd definitely like to make some more videos. I might do some guitar and/or effect build videos soon.

[@vikingsofvintageaudio7470]

@@insanecomicdude Do it!! I like the more high level, like the fact that you don't go in to all details like what compression is and so on. Generally, 99% of all of these videos are basic and that's great and all but it's fun with videos that assumes you already know some stuff and you get to learn something new instead. Thanks again!

[@insanecomicdude]

@@vikingsofvintageaudio7470 one I was thinking of was like a "how to get started building pedals" with a very basic boost pedal design (which I would dub "stupid boost"). Go over the tools you need, how to solder it, how to make the pedal, how the circuit works, etc.

[@vikingsofvintageaudio7470]

@@insanecomicdude That's a great idea! I've been filming some around the exact same topic but haven't released it cause I got stuck in the "got to explain each step"-thing but maybe you really don't need to do that. I have some really fun and novel pedal / gear ideas I've been wanting to both build and record while doing. Maybe I should get at it again!

[@insanecomicdude]

@@vikingsofvintageaudio7470 you definitely should. My plan is to kind of explain with block diagrams and maybe the actual circuit, but not get too deep into the weeds. Just focus on the parts that matter.

[@AP-qn6br]

Sound brilliant, i am using it in a similar way in my effects chain. the Joyo compressor is also good, just have to wind up its sustain higher.

[@insanecomicdude]

Is that the green one with the scorpion on it? I think I have one of those. I'll have to give it a try.

[@Peter-fi5mv]

10/10 explanation dude. 🤘

[@MichaelDespairs]

Rather than mimic sag I like to set the attack time really fast. It makes it squishier, louder, and more transparent.

[@insanecomicdude]

Like as fast as possible? Do you do that more for less-distorted stuff?

[@MichaelDespairs]

Anything faster than 50 ms or less works for me since I'm usually trying to smooth out pick attack in high gain tones. For clean and mid gain I might slow it down for more of an RMS squeeze depending what's being played.

[@ducacalainho]

Great video man, congrats. Very useful.

[@insanecomicdude]

Thanks! Glad you liked it.

[@voxpathfinder15r]

If you ran your amp really clean with lots of headroom and used a distortion box in the front for all the dirt- you could think of it as pulling the preamp of the amp outside in front of the amp. In this case you could conceivably put the compression pedal after the dirt pedal which would be similar to putting it into the effects loop like in your example. The thing is I learned that order was bad practice since a compression pedal will raise the noise floor of a distortion pedal. Do you find noise to be an issue with your setup?

[@insanecomicdude]

That would totally work, yeah. Or at least it would be effectively the same. I didn't notice a ton of noise when I did it last, but my gear is in a pretty noisy room, electrically, so I may have just not noticed. It does make sense that it would raise the noise floor but I bet while you're playing the Snr would be high enough it wouldn't matter. A gate would probably take care of the rest.

[@insanecomicdude]

Of course, I regularly play with single coil p90s into high gain, so maybe I'm not the best person to ask about noise :)

[@marcellorinaldi5554]

noise floor come because usually you raise the overall level with the compressor (manually or with auto-gain): to work, you should just use the compressor to cut the highest levels, as a limiter, no gain increase at all when idle...

[@nigel900]

Very interesting. I’m wondering, when the sustain is increased (at or past noon), does the note sustain and continue when configured in this way?

[@insanecomicdude]

probably not a notable amount. We're already getting a ton of sustain from the overdrive.

[@dannyrivers3922]

Damn that's cool! Genius!

[@jahimsa4353]

So funny, I had this same idea the other day to try to emulate tube rectifier sag, since a tube rectifier comes after the preamp. Incredible video man, I havent been able to try this out myself, but this confirmed everything. Here's a question tho.. So I'm using a Hot Rod Deluxe. Lets say I put a compressor similar to the one you are using in the effects loop, and use the sustain as you do, but I find that I want more clean headroom out of my amp (if that makes sense).. Could I raise the master volume on my Hot Rod Deluxe and lower the level knob on the compressor to achieve this? A more basic/open way to ask this would be.. what does lowering/raising the level knob on a compressor in the effects loop?

[@insanecomicdude]

On this particular compressor, I believe the level knob is simply a master volume on the pedal itself after the effect. I think if you want more clean headroom you would just need to decrease the amount of compression (decreasing sustain, or increasing threshold, depending on the controls on your particular pedal)

[@hungryguitarstudent]

Nice tutorial !! Very clear explanation, good stuff man !

[@murdahorse]

Nice explanation, cheers!

[@pabcrane]

Great explanation. Does this hold true for a clean amp? With a Dyna Comp (no Attack control) would the settings on Sustain and Level require anything radically different?

[@insanecomicdude]

Level will do the same thing, but sustain might be different. Sometimes "sustain" adjusts the input level going to the compression circuit (as seen in my video) - giving you more compression as you turn it up because you are driving the control circuit harder. Sometimes "sustain" adjusts the ratio of the compressor, meaning it increases the amount the signal is attenuated per increase in input volume. The second option is going to feel less like a "volume knob" like I showed in my video, but it may still give you a similar effect. Try it out and see!

[@insanecomicdude]

Oh and as far as the clean amp goes, the compressor will still compress, but the results will be a little different because the level of the input signal changes as the note decays. But with a slow attack, you'll still get an overall even signal but with intense pick attack, even clean.

[@billwilliams6338]

You installed a Resistor "in series" or " in parallel" on the rectifiers output? This will change the RC time constant of the filter capacitors. I'm not sure why the filter capacitors are draining off. I think the filter capacitors are just "following" the B+ voltage not draining off.

[@insanecomicdude]

In series. Think of the amp as having two states. Playing and not playing. Let's say our PT outputs 300v. When not playing the current draw is, say, 50mA. If we have a 200 ohm resistor between the rectifier and the OT B+ TAP, that means when not playing, we drop 10v across that resistor, meaning our plates are sitting at 290v. However, when playing, our current draw might rise to 100mA. This doubles the voltage drop to 20v and drops our plate voltage to 280v. But because there's a big cap at the OT it takes some time to drop from 290v to 280v. So we get that transient volume drop as the headroom is a touch higher on the initial attack before the caps drain.

[@NecrosisF]

Great video, thanks for the explanation! I have a Mooer ge300 and It doesn't have an amp sag control like the helix, but it comes with Bias, master and preamp out. I tweaked it a lot, with compression in the fx loop but the sag is not close for what I'm looking for. Do you know how can I emulate the sag with these controls?

[@insanecomicdude]

The only thing I can think of would be to play more with the built in compressor options. Look for one with an adjustable attack time and slow it down. 30ms is a good starting point. Good luck!

[@NecrosisF]

@@insanecomicdude thanks for the advice!

[@toddegoldberg]

I'm interested to hear what you think of the Hughes and kettner black spirit 200, as they claim to have figured out sag controls for solid-state amps. Is it possible they just integrated a compressor into the unit to act similarly to what you achieved here? Either way this amp is interesting.

[@insanecomicdude]

I was wondering the same thing, actually. I'd say it is definitely possible.

[@jeddak]

It's interesting to note that Thomas Blugh, developer of the BluGuitar AMP-1 (which features sag but with a class D power amp) used to be one of H&K amp designers. And that the Black Spirit 200 adopts the same little "tube-in-a-window" motif that we see on the AMP-1......therein lies a story, I think.

[@billwilliams6338]

What can you do to a guitar amplifiers power supply to increase the SAG and decrease the SAG? how can you increase the powers supply current, you would have to change replace the AC power transformer to have more secondary current amps?

[@insanecomicdude]

I built an amp once where I simply put a high wattage resistor in the power supply after the rectifier and before the b+. So when the power amp is idling there is minimal current and hence minimal voltage drop across that resistor. But when you play, the power tubes pull more current so that voltage drops, and the b+ caps drain over a few ms from the max b+ to a lower value. Thus: sag.

[@Lavabug]

You can lower the value of the filter capacitors after the rectifier.

[@insanecomicdude]

@@Lavabug wouldn't that introduce more hum in the preamp stages? I suppose they have further filtering of their own so maybe not.

[@11calman]

Wow mate that was great,,, Thanks

[@jeffhirata]

Great explanation. Thx!!!

[@atomicleaf]

Hi there, sorry to resurrect an old discussion but I have a question for you. Elsewhere in the comments you said that if one was to us other pedals in the fx loop (delays, reverb, etc) that the compressor should go before them. Is that because the other effects will mess with the transients? Given the nuanced effect we're going for here and what we're trying to simulate, I would have guessed the compressor would go at the very end of the effects chain.

[@insanecomicdude]

I see what you're saying! If you wanted to simulate an amp with reverb then yeah I think putting it at the end of the chain would make sense. Maybe! I think a lot of the compression probably comes from voltage drop in the preamp, which would probably mosty be be before the reverb. Either way I think it's worth a try!

[@ramonrodriguez4372]

is there any way to achieve this without an effects loop.

[@insanecomicdude]

You can get the same effect if you use the clean channel on your amp and put a distortion pedal before the compressor. Unfortunately you can't use the distortion from your amp, but it'll have the same effect.

[@ramonrodriguez4372]

ya thats what i was thinking. i have a orange rocker 30 head. no effects loop but a super transparent natrual channel

[@isaacgarcia878]

Is this a similar idea like when Van Halen cranked his Marshall and used a variac to turn the power down...he tube sag when he did this

[@insanecomicdude]

Cranking it: yes. Variac: maybe. The variac would lower the power supply voltage (Vs), which reduces the headroom of the amp and thus increases saturation. It's possible that the variac could also affect the transient response (the sag), but I do not know.

[@solihinahmad6030]

but the variac lowers the input supply voltage to whole amp circuits. I wonders if anyone had ever achieved by modulating the Vs supply dedicated to power section. Power scaling mod achieve the tone of cranked tube but at lower apprehensible volume. But i i doubt power scaling technique achieve the same result. londonpower.com/power-scaling-faq/

[@mattgilbert7347]

That's a clone of the old Ibanez CP9 (or Maxon, I forget - so many Ibanez pedals were OG Maxons or built by Maxon, I believe) A Comp/Limiter is better than a Comp/Sustainer when placed post-gain, yeah? That's what I've gleaned from various sources. I've tried Comp/Sustainers after gain, and unless they have a clean blend the results have been a bit wonky (that's a technical term) Cheers, informative video. I didn't understand a lot of it. But thanks.

[@insanecomicdude]

Thanks! Limiters seem to be better because they generally have an attack time adjustment. At least that seems to be the case.

[@whatwouldhousedo5136]

0:21 What type of cat is best for this?

[@insanecomicdude]

I use an orange maine coone mix, but most modern breeds will work well.

[@vivekmehta5172]

One of the main differences between real Amp Sag and Compressor is When a Tube Amp sags, it increases the distortion (and it also compresses the signal amplitude) While the compressor only changes the signal amplitude So a real amp has change in harmonic content and change in volume as it sags While a compressor only has change in volume.

[@insanecomicdude]

Yep, totally correct. I think for a very distorted signal like this though, any difference would be unnoticeable. For lower distortion though, I imagine it is more noticeable.

[@jimgillis8522]

So my distortion is last in my chain sounds better with compressor off? Cleaner tones are great tips?

[@insanecomicdude]

Well if you want to try this tone, put a compressor after your distortion. It might sound better. Or worse! Only one way to find out.

[@trentkraemer7109]

Doesn’t it actually soften the attack as opposed to increasing the transient? I’ve been researching this more and even through looking at waveforms from songs it seems like the notes actually bloom in volume.

[@insanecomicdude]

It can! Depends on your settings. A slow attack will preserve the transient (because the gain reduction doesn't kick in until the transient is past). A fast attack however will clamp down the gain as the transient occurs and thus soften the transients.

[@isakstruck73]

Im far from a tech. But as i understand it, the satisfaction of sag isnt because if the compression of the signal alone. Rather, its the combination of compression and dynamics between clean and dirty tones. When the available voltage lowers, the headroom will also lowers and the power amp will distort more easily. This will make it more easy to go from clean to dirty only depending on how hard you play. None of this is happening with a simple compressor. Think of it more like you put a gate in parallel before the distortion pedal, plus a compressor after!

[@insanecomicdude]

That makes a lot of sense. To that point I don't think this mimics sag for anything other than high gain tones. It would be interesting to build a pedal that compresses by lowering headroom.

[@isakstruck73]

@@insanecomicdude Yes, or a tube preamp. But as i understand, it can´t be done without without any kind of simulation. A compressor of some sort that reacts to input signal but compress the voltage to the preamp tube instead of the signal it self. The preamp tube runs in class a and will not draw more voltage when pushed to the limits than it does at idle, as i´ve been told. Perhaps a push pull preamp would cause some sag in the psu!?

[@insanecomicdude]

@@isakstruck73 yeah I'm thinking you run some kind of push pull amp into a low wattage dummy load within the preamp, and just give it a bad power supply. Hell the simplest thing to try would be an op amp with a bad power supply driving a resistor load that's small enough that the op amp pulls a bit of current when it has a signal. Or maybe one of those 1w audio chip amps driving a chunky 8ohm resistor. And then put an RC lpf on the vcc for the chip amp. Calculate the value so that it will sag. Worth a try. Might have to build it.

[@isakstruck73]

LiveOVErdrive i think you should build it, both ideas sounds good! Im wondering if an expanderar in front of a tube pedal and a compressor after would give me the satisfying threshold between clean and overdrive, might be too sudden. Local negative feedback also give some of this effect from what i know. Have no experience so i cant tell.

[@timec818]

Thanks good explained 👍

[@billwilliams6338]

Yes I understand, but without installing a series resistor. A Tube amplifier has SAG because the tube amplifiers power supply output current limit can't output enough current. This is why the voltage drops on the output tubes plate voltage. How can you increase the power supply in a tube amp to prevent sagging? Install a higher amp Power Transformer so the secondary winding has more current output or the tube rectifier is not outputting enough current to the power tubes? Is there a way to put a send and return jacks inputs after the power amplifier before the speaker? What compressor pedal parameters knobs would you need to get very similar SAG effects like tube amplifier?

[@insanecomicdude]

You can't put anything between the power amp and the speaker. They are basically one system. If I understand what you're asking I would say just put a compressor in the effects loop like I do in the video. Should get close enough.

[@juniorg296]

This is one of the best explanations of any thing I've ever watched on KZbin. Also what black magic are you using at 1:16 to draw one line and have the rest of the triangle draw itself???

[@insanecomicdude]

Thanks! If you level up your pen skill high enough you can unlock the "jump cut" perk.

[@DareBear2099]

Can this punch work in an amp that has a solid state power section? I have an Orange Micro Dark with a Solid State Class AB power amp section. I thought putting a compressor in the FX loop would mimic the tube sag effect? Would it work the same way or does it have to be a tube power amp section.

[@insanecomicdude]

It would definitely work. The idea here is that the compressor mimics the tube sag so you can run the output from that into any power amp and get that saggy punch.

[@DareBear2099]

@@insanecomicdude Following question, could I put other effects in my loop with the compressor? I have a line 6 M9 I use for delays and reverbs.

[@insanecomicdude]

@@DareBear2099 yep. Just put them after the compressor.

[@DareBear2099]

LiveOVErdrive put a tube compressor in the FX loop of my Micro Dark... wow! It sounds awesome! Threw my Blues Crab Overdrive in the front and It’s almost a new amp!

[@insanecomicdude]

​@@DareBear2099only seeing this now, four years later, but that's awesome! Congrats on the "new" Amp.

[@dimitrikovalchuk2405]

Nice video!

[@insanecomicdude]

Thanks! Glad you enjoyed it.

[@FEVfallout]

Will tc electronic Forcefield Compressor work as good or better?

[@insanecomicdude]

I haven't used one before, but it seems to have an Attack knob on it, so it should work just fine.

[@leodowney1244]

I had a harmony H303a, a 62 original jennsen speaker, 1power tube, 1 pre amp tube, and 1""Tube rectifier. That's the secret, TUBE rectifier, w/ my boss turbo overdrive '"my only boss pedal"" turn those knob's all the way up. It's insane, just like Norman Greenbaum's spirit in the sky sound. But I had a lil more saturation and madness.All the "tube amp's'''' from guitar center, ams, musician's friend. Fender, marshall. If it doesn't have a tube rectifier, and has circuit board's. It's trash. I also used to hate EHX pedal's but then I realized that horible sound was the fact that I was using a cheap solid state amp. So I got rid of that, I got some 60s amp's, all real tube and analog pedal's only. Now people love my sound. All analog, high voltage stuff, Except my electro harmonix sovtech russian big muff. For that insane sound. Space hog, smashing pumkin's cherub rock, crazy sound.

[@insanecomicdude]

I have a similar hand wired amp from the 60s with a tube rectifier and it sags like nothing else when cranked. It's an old PA amp that I converted to have a jcm800 2204 preamp (or close to it). I don't think pcbs make a difference (other than indicating the amp is probably newer and has a "better", less saggy power supply.). It sure sounds great.

[@TheTruth70777]

Will this work with solid state amp, or atleast hybrid one ( tube preamp, SS power amp) thanks!

[@insanecomicdude]

Yes it will! You could even do a distortion pedal into a compressor into a class d power amp and get the same effect.

[@billwilliams6338]

How do you bias a amplifier, do you measure each tubes plate and cathode current and try to match them?

[@insanecomicdude]

I've only done it once because all my amps had fixed bias until recently. I measured the cathode current one one tube and adjusted to the level I wanted. Then I checked to make sure the other one was similar.

[@billwilliams6338]

But eddie van halen put guitar effects "after" the power amplifier before the speaker, how did he do this? He had a send and return jacks "AFTER" the power amplifier. When Randy Rhodes and Eddie Van Halen put an AC variac set to 90VAC this lowered the B+ voltage and plate voltage down to what voltage? and why does this damage the amplifier when lowering the B+ voltage and plate voltage?

[@insanecomicdude]

If he put his effects after, they were probably in the effects loop (I. E. Between the preamp and the power amp), OR he likely played into the amp, miked the cabinet, and put the effects after the microphone (like in the studio). Tom scholz did that a lot back in the day. Lowering the B+ is probably not a problem, but lowering the input voltage to the amp also lowers the heater voltage, which could damage the tubes (since they'd be running out of spec)

[@rangerdoc1029]

How do sustain & level differ in this application?

[@insanecomicdude]

Level is just a clean volume adjustment after the effect. Sustain behaves like a master volume before a power amp. As you turn it up it pushes the power amp more.

[@jeddak]

But what does the cat think of all this?

[@insanecomicdude]

He's overall pretty okay with guitar playing. Especially since it means he can scratch his face on the tuning machines.

[@theruel]

Very nice! (littlebadboy)

[@Caged63Man]

Wow amazing..you just made the tone sound even cheaper imho!

[@billwilliams6338]

So lower the plate voltage won't damage the power tubes? To bias a tube amplifier you measure each power tubes plate current or cathode current. Matching each current per tube, if all 4 output tubes have different plate currents the cross over distortion is wider at the zero crossing point. When all 4 output tubes match current per tube there is no cross over distortion at the zero crossing point? Eddie van halen put effects in the line output jack but somehow used a load attenuation box on the speaker to send the guitar effect back to the speaker again. Eddie Van Halen didn't use the send and return jacks it was a different way

[@insanecomicdude]

Well I'm not sure on that actually. If the tubes were self biased the change in voltage wouldn't do much but yeah for power tubes with a grid bias I'm not sure what would happen. Interesting about evh. I'm not sure what he did.

[@Joshcheyka]

Good explanations, however get a tube amp if you want a tube amp sound. Compressor helped a bit, but still could hear the flatness/dry sound of the transistor amp.

[@insanecomicdude]

It's a Mesa Mark V, which is most definitely a tube amp. It is, however, a generally pretty dry and tight tube amp, which is where this trick can come in handy.

[@Joshcheyka]

@@insanecomicdude 2 years on, I'm actually quite surprised by what I commented, I must have been watching a lot of bs videos that night and been overwhelmed...I'm now a huge fanboy of a compressor over a Boost/OD and in general especially on cleans!. I must say when I initially bought my compressor I wasn't very impressed, but I've got it dialed in and the tones are just a world away from what I used to sound like and I think it gives me an edge. I now have a Boss CS-3 Compressor and a DBX166 Rack mount that I switch between... the DBX sounds amazing in the loop. Also my apologies on calling it a transistor amp lol in fairness like you said it is a bit dry sounding. Its a great demo and I wish I had paid more attention to this video the first go around. I was very fresh in the world of compressors then.

[@insanecomicdude]

​@@JoshcheykaI'm only just seeing this now. Nice to hear from you again! Ironically nowadays I AM playing a solid state Amp. And this compressor trick is coming in very handy.

[@andrewdenine1685]

Sounded like more of a noise gate to me

[@insanecomicdude]

Interesting. Maybe you can get a similar effect through different means.

[@johnsimms3957]

I don't know why anyone would want this. When I play a note or a chord I want the sound to come out immediately from the speakers. I don't want any sag.

[@insanecomicdude]

It's a particular tone. Modern metal tones favor a really "stiff" sound (no sag). This effect can be really nice to get a punchy rhythm or lead sound with a vintage flair. It gives you the feel of pushing your equipment to the max without actually doing that.

[@vandal_dk]

John Simms Sag is life.