Tube amp users: Do you keep your power amp sim switched on?

Stringtheorist

Stringtheorist

Fractal Fanatic
I keep my power amp sim switched on all the time with my VHT 2/50/2 because of the wider range of control it gives me over tone, particularly with respect to clean/mild-breakup sounds. In my heavier presets I'll tend to keep the Master and Sag low to account for the fact that I'm driving the power amp around half volume at gig level.

Lately, I've noticed that heavily distorted presets always tend to sound a bit "spongey" and lacking in punch, even though I routinely use the low cut, filter and drive block tricks to tighten the low end. I do wonder how much improvement I might hear in these presets if I were to disengage the power amp sim (Sag=0) but I'm only in a position to muck around with presets at gigging volume when I'm at rehearsal, not sitting at home. How do other amp users dial in their Axes for use with (tube) power amps? Do heavily distorted presets sound much better this way?
 
With my mesa 2:90 i use power amp sims on with heavy gain patches.....gives me a more interesting, less sterile sound...but like you said.... its easy to sound too spongey so i set sag damp and master volume accordingly. Clean wise i use sims on for breakup tones and off for clean clean tones.

Although deep is a poweramp parameter, I really wish it would still do the same thing with with poweramp sims off. I find with high gain tones i need to boost the lows with a peq quite a bit. FWIW i use the modern setting on the 2:90 but not the deep mode, its way over the top IMHO.

Im curious as to where tube amp users set their presence on the axe-fx sims.... power amp sims of or otherwise.
 
I often wonder how much of what I'm hearing is down to the speaker/cab part of the equation, and how much down to the power amp. I'm also considering swapping my bridge pickup again (BK VHII) as I think it's too midrangey for what I'm trying to use it for (Zakk Wylde/Metallica types tones, amongst others). The midrange sounds somewhat poorly defined and congested, if you will. Did a quick full volume blast for a few seconds on the Brit 800 model.... By the time I'd tamed the highs to the point where my ears weren't bleeding the tone become dull and congested again. I guess I gotta play with a PEQ block. :|
 
I have a Mark Iv on the loop with the Axe.. I use the powersims on all the time but I keep the Sag level low like 8 o clock. Also I use a FR setup with it and is the best combination I have achieved so far... going over 9 o clock makes the sound very spongy as you said, losses definition. So with High gain patches... definitely sounds much better with sims on. If I let them out sounds very sterile... the Clean patches also benefit a lot with sims on. Before using my FR speaker I was using PEQ to restore the tone I felt I was loosing with the sims off. Once I changed to the FR I noticed that all the PEQs that I was using became obsolete and they were messing with the tone. I set all EQ flat and remove all PEQ on my patches... and I am happy now.
What speakers are you using?
 
joeymexico said:
I have a Mark Iv on the loop with the Axe.. I use the powersims on all the time but I keep the Sag level low like 8 o clock. Also I use a FR setup with it and is the best combination I have achieved so far... going over 9 o clock makes the sound very spongy as you said, losses definition. So with High gain patches... definitely sounds much better with sims on. If I let them out sounds very sterile... the Clean patches also benefit a lot with sims on. Before using my FR speaker I was using PEQ to restore the tone I felt I was loosing with the sims off. Once I changed to the FR I noticed that all the PEQs that I was using became obsolete and they were messing with the tone. I set all EQ flat and remove all PEQ on my patches... and I am happy now.
What speakers are you using?
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V30s in a 2x12 cab. What is your FRFR setup?
 
I am using a BEYMA 12XA30ND COAXIAL SPEAKER on a boogafunk Cab which is a 3/4" dual ported cab with Crossover and special caps. I made a thread about it just search it on the database. The only drawback I can see is that at lower bedroom volumes the speakers sound out of treble, dull... hell this are very powerful speakers so I guess they are more for gig use not for bedroom practice and the ART seems to be a little harsh and not to flat as they said...... , but well for bedroom usage I guess a pair of studio monitors would be best.
 
Similar setup to you. Cab is 2x12 with one V30 and one G12H, set up in 3/4 back mode (though it is ported too). I leave my sims On for everything. I just cant work out where to set the voicing switch (out for gigs, in for low vol at present) or input gain. To the previous poster, I used the Art prior to the VHT in the pic. I found the amp (in comparrison) to have a be dull top end and muddy bass. The VHT sorted ALL that out - I didnt even know I had a problem. Only tried the VHt because the OP is picky picky about his tone ;) and went through LOADS of options - both amps and FRFR before finally betting happy (ish?) with the VHT.

SDC11619-1.jpg
 
paulmapp8306 said:
Similar setup to you. Cab is 2x12 with one V30 and one G12H, set up in 3/4 back mode (though it is ported too). I leave my sims On for everything. I just cant work out where to set the voicing switch (out for gigs, in for low vol at present) or input gain:
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Yeah, I'm having that trouble too. Generally I find the voicing switch makes everything too bright and prone to feedback at gigging levels, but improves the sound considerably at low volumes, so I only use it for practicing/setting my patches up. When setting the volume somewhere between those extremes, then I have problems deciding how to set it.
 
Yeh. I tend to raise the presence on mid volume settings but dont engage the voicing. Its kinda OK for the top freqs - its the bottom im fighting. With the voicing "bright" the Bass is tight - on "normal" its thicker. I find when the volume is raised above bedroom vols, the voicing needs switching from bright to normal; for the upper freq BEFORE I want to for the Bass ones.

The only way round Ive found (and its a bit of a cop out really) is to set the depth midway, and presense off and adjust patches from there. Then When I lower the volume, I can raise the presence and lower the depth as required.

As for volume - Its not obviouser. The two levels are -10 and +4 bd I think, however as the axe has so many ways to raise/lower its OP its difficult to know what level is comming out!!. As I leave the sims on I want clean power so dont want to overdrive the VHT. At present I have it set "low" but my out in Global is set at +5db. Gives me enough volume with amp and Axe front Gain/OP maxed without distorting - and I cn get quite enough for night time bedroom noodling I f I and (rather than going onto my MBox direct and using phones).
 
I have 2 x 2/90's, modded to be cleaner, voicing circuit bypassed, 6L6's, increased power supply voltage and more. I set the presence at noon, definitely prefer using the Axe 3 with power amp section off, too squishy and not as much detail with it on.

BUT, I prefer my Matrix into the same cabinets with the power amp modeling on, over the 2/90 setup. It has significantly more detail and the bass is more graduated and tight. In that situation the power amp modeling does exactly as it should and the high gain sounds are huge through a more neutral back end...
 
stereotactic said:
I have 2 x 2/90's, modded to be cleaner, voicing circuit bypassed, 6L6's, increased power supply voltage and more. I set the presence at noon, definitely prefer using the Axe 3 with power amp section off, too squishy and not as much detail with it on.

BUT, I prefer my Matrix into the same cabinets with the power amp modeling on, over the 2/90 setup. It has significantly more detail and the bass is more graduated and tight. In that situation the power amp modeling does exactly as it should and the high gain sounds are huge through a more neutral back end...
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So yeah, we're talking right at the margin here. I tried setting SAG to .01 so the power amp sims are still on, but not making it "squishy" but then we both probably learned the same thing that when you turn the PA off entirely, you lose A LOT of the character of the amp.



What I learned from this clip is the axe-fx PRE simulation

1. Not as good as I thought
2. Not driving the power amp (you can tell the PA is not getting excited by the input from the Axe-FX as a preamp resulting in a softer output with less sustain)

What we learn about the power amp is that it provides a LOT here that simulation can't get IMO. The worst tone here is Axe-FX in the whole signal chain IMO.

EVEN WITH the actual VH4 power amp, the Axe-fx adds a lot of "fizz" to the PA. I suspect a tube pre in front of the axe-fx or in the loop will solve that problem and found some evidence of that. I also suspect running the axe-fx as line level and then boosting the output just a touch will correct the softness issue from the video.

https://www.thegearpage.net/board/i...e-buffer2-review-used-with-the-axe-fx.786332/

I am skeptical of the "tube thickness" of the Matrix. I'm not talking about SAG in this case, but there's just an ever present level of BALLS that tubes have that touches every iota of the output. If I have to compare it to something, lets call it "mouthfeel." Ever had some decent olive oil? How it takes over your whole pallet, that's what I'm talking about.

Speaking to the 2:90 we can say this is 9 oclock vs 2 oclock. Once you're at 2 oclock can the matrix replicate that? At 2-pegged oclock on the 2:90 (with axe-fx level at -30).

To be clear, I'm not trying to nail exact tones. I was hoping and was somewhat confident that the axe-fx could replace preamps, but I'm skeptical at this point.

The idea was that I'd have a group of actual poweramps, 6L6, EL34, EL84 etc and then route each patch to its actual PA style with the tonestack in place as well as PA simulation with "ideal" for the tube style. The idea was that the tube simulation would exceed the envelope of the actual tube and the actual tube would function as a pass filter to cut it down to the exact tube profile (6L6, EL34 etc).

To be clear, I'm not trying to nail the amp tones. I just want, pure, real, amp tone, which I can make my own. And I get that the matrix sounds great, my FRFR stuff sounds great. It really does. But I'm looking for real amp tone, that put through a real microphone, will sound like a real amp. Not a recorded amp before its been recorded.
 
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Elan Vital said:
So yeah, we're talking right at the margin here. I tried setting SAG to .01 so the power amp sims are still on, but not making it "squishy" but then we both probably learned the same thing that when you turn the PA off entirely, you lose A LOT of the character of the amp.



What I learned from this clip is the axe-fx PRE simulation

1. Not as good as I thought
2. Not driving the power amp (you can tell the PA is not getting excited by the input from the Axe-FX as a preamp resulting in a softer output with less sustain)

What we learn about the power amp is that it provides a LOT here that simulation can't get IMO. The worst tone here is Axe-FX in the whole signal chain IMO.

EVEN WITH the actual VH4 power amp, the Axe-fx adds a lot of "fizz" to the PA. I suspect a tube pre in front of the axe-fx or in the loop will solve that problem and found some evidence of that. I also suspect running the axe-fx as line level and then boosting the output just a touch will correct the softness issue from the video.

https://www.thegearpage.net/board/i...e-buffer2-review-used-with-the-axe-fx.786332/

I am skeptical of the "tube thickness" of the Matrix. I'm not talking about SAG in this case, but there's just an ever present level of BALLS that tubes have that touches every iota of the output. If I have to compare it to something, lets call it "mouthfeel." Ever had some decent olive oil? How it takes over your whole pallet, that's what I'm talking about.

Speaking to the 2:90 we can say this is 9 oclock vs 2 oclock. Once you're at 2 oclock can the matrix replicate that? At 2-pegged oclock on the 2:90 (with axe-fx level at -30).

To be clear, I'm not trying to nail exact tones. I was hoping and was somewhat confident that the axe-fx could replace preamps, but I'm skeptical at this point.

The idea was that I'd have a group of actual poweramps, 6L6, EL34, EL84 etc and then route each patch to its actual PA style with the tonestack in place as well as PA simulation with "ideal" for the tube style. The idea was that the tube simulation would exceed the envelope of the actual tube and the actual tube would function as a pass filter to cut it down to the exact tube profile (6L6, EL34 etc).

To be clear, I'm not trying to nail the amp tones. I just want, pure, real, amp tone, which I can make my own. And I get that the matrix sounds great, my FRFR stuff sounds great. It really does. But I'm looking for real amp tone, that put through a real microphone, will sound like a real amp. Not a recorded amp before its been recorded.
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I think I understand what you're getting at, and I agree that there are things going on with the real half stack setup that are not identical. That being said, I think the brighter tones might actually sound better with the Axe to my ear, but of course this is just going by a mic'd FRFR cabinet, not being in the room. Another factor that may account for the disparity between the model and the real thing is the way the real amp and cabinet are interacting with the room. Just as with studio monitors, a big cabinet in a small room like that can really excite certain room modes. You are almost certainly overloading that room with the 412, which would cause some pretty big low mid range peaks/standing waves and might make the real set up sound more forceful and big.

To be clear about the power amp descriptions I wrote above, the Matrix is obviously not a tube amp and I don't believe they were striving to directly imitate one. If I understand their design philosophy correctly, they were trying to make sure that it's transient response was up to the task of dealing with guitar, and in a flattering way. I don't remember what the literature says exactly, but I have used several high powered SS amps and my 2k Matrix is definitely the best sounding of them all in terms of its frequency response and impact.

To my mind, there is a trade-off between a real tube amp which has a certain basic response and roundness to the sound as it starts to clip, against a more accurate, detailed reproduction of what is being input, as in an SS amp like the Matrix, which you should never clip. One may decide they like the sound of a driven tube power amp better for certain particular tones, but this will limit your ability to reproduce other things clearly like reverb, delays, phasers etc. I have been striving for a more neutral back end for just this reason. I use effects and want the most resolution possible, while crafting as much real amp tone in front of them. The Axe allows you to do this with tremendous precision and depth, though reproducing this in a way which is maximally satisfying can be a challenge for those of us who like a big, loud traditional 412 high gain sound.

If you're going to keep pursuing your sound with the Axe you might want to consider an intermediate step between that stock regular 412 cabinet with speakers designed to break up when being pushed by 100 W head and full FRFR. Instead, try a cabinet with higher wattage 12" speakers like EV 12Ls or Emminence Delta Pro 12As. The cabinet should also be designed around them, meaning tuned and ported correctly for their wider frequency response. These types of cabinets are not common, mine are custom, but I think the Mesa Thiele cabinets are closest in terms of necessary rigidity, mounting and porting. Looks like they still make the 112, I think there were 212s and maybe a 412 design a long time ago. I'm sure there are plans out there for 412 Thiele or similar ported designs. With a high wattage speaker in a properly designed, ported 412 you will get all the air moving and coupling effects of a lower wattage design stock type 412, but with greater clarity and tighter low end. And then you can try that with an SS amp and a tube power amp and hopefully find a sweet spot of clarity and umph that will allow you to get the most out of the Axe...
 
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Elan Vital said:
So yeah, we're talking right at the margin here. I tried setting SAG to .01 so the power amp sims are still on, but not making it "squishy" but then we both probably learned the same thing that when you turn the PA off entirely, you lose A LOT of the character of the amp.



What I learned from this clip is the axe-fx PRE simulation

1. Not as good as I thought
2. Not driving the power amp (you can tell the PA is not getting excited by the input from the Axe-FX as a preamp resulting in a softer output with less sustain)

What we learn about the power amp is that it provides a LOT here that simulation can't get IMO. The worst tone here is Axe-FX in the whole signal chain IMO.

EVEN WITH the actual VH4 power amp, the Axe-fx adds a lot of "fizz" to the PA.
Click to expand...


Have you ever heard a real amp’s preamp only? It too is fizzy. Yes the Pre and Power amp need to work together to create the tone. How loud were you playing the Axe pre signal into the power amp and cab? Real amps need the speakers to be pushed and the power amp to be turned up, so it’s the same with the Axe as pre.

People all around the world use the Axe into a real power amp and cab and it sounds great. So I’m not sure your conclusions represent the gear as a whole.

Even back in the Ultra days, I ran it through the many high end amps I had at the music store I ran, and as a replacement for the Pre, it sounded amazing at volume. We A/B’d the models vs the real preamp and it was very close - and this was back in 2009.

There may be something that needs to be adjusted in your setup. Again, the sound of the pre-only from a real amp does not sound good at all alone. The power amp does create a bunch of the resulting tone and things just have to be used properly.
 
chris said:
Have you ever heard a real amp’s preamp only? It too is fizzy. Yes the Pre and Power amp need to work together to create the tone. How loud were you playing the Axe pre signal into the power amp and cab? Real amps need the speakers to be pushed and the power amp to be turned up, so it’s the same with the Axe as pre.

People all around the world use the Axe into a real power amp and cab and it sounds great. So I’m not sure your conclusions represent the gear as a whole.

Even back in the Ultra days, I ran it through the many high end amps I had at the music store I ran, and as a replacement for the Pre, it sounded amazing at volume. We A/B’d the models vs the real preamp and it was very close - and this was back in 2009.

There may be something that needs to be adjusted in your setup. Again, the sound of the pre-only from a real amp does not sound good at all alone. The power amp does create a bunch of the resulting tone and things just have to be used properly.
Click to expand...

To be clear I'm being very picky here. I've gotten to the point where I believe my beef is with emulation itself. There is a certain grind\fuzz that processed sounds seem to have that harkens back to even Gen 1 type stuff like the Digitech 2120 etc. It has to do with IMO using math to generate sound. Just like computer generated car sounds have a certain sound to them (not speaking of sampled sounds).

It is very close and it is a valid approximation, but I do truly believe the special sauce of tubes themselves are in fact missing. I do believe this can be rectified with a tube pre given the examples I've seen to give that "mouth feel" to the pre. I also believe the Axe-FX offers exciting possibilities by offering pre-amp sounds that may not even be able to exist in terms of physics, so that is exciting to me.

Lastly, I've very much warmed to the idea of using a SS with a tube power amp, as the clarity and immediacy of SS can't be discounted as a benefit. I have a lot of sandboxing to do before I get to my sound, but I think I'm pretty close. And it feels pretty damn good to have such powerful tools at your disposal.

I think I may just be one of those obsessive types where I'm isolating every small issue on my way to my own personal perfection. I think a lot of guitarists are this way. That's how things like Variac, Floyd Rose tremolos etc etc all made their way into the guitar world. One persons obsession with chasing tone moved the goalpost another foot.

I will reach out to another user who I believe might be able to validate this theory who actually owns a Soldano preamp, which seems to be the best example of the limitations of mathematics for emulation. I wonder with a tube pre if the Soldano pre model will in fact be much closer to the real deal.
 
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