The Poweramp

[Alex Kenivel]

I pour Katana sauce all over my Helix tones and it sounds and feels great. Cue the gagging sounds

 

[jay mitchell]

What constitutes a good power amp depends on how you use a modeler and on your performance targets. If you're not using cab sims, you've already committed to using a physical example of one of the three things modelers simulate: preamp, power amp, and cab. If you also use a (guitar-centric) tube power amp, you're now using two of those physical items and therefore not using the modeler's simulations of them. It's worth noting that, even if your tube power amp sounds clean to your ears, it's adding substantial nonlinearities: distortion, saturation, and/or compression. Those nonlinearities are additional to those produced by the modeler.

A tube power amp will inevitably have a "sweet spot" which will vary from cab to cab and from player to player. That sweet spot will occur at a specific volume. IME with the amps I've used, the sweet spot has been too loud for practice. Depending on the amp's power and the gig requirements, it was sometimes not loud enough for gigs.

In order for a neutral power amp to work with a guitar cab, the modeler must do an acceptable job of simulating both the preamp and power amp sections of the amp being modeled. If a neutral power amp does not work to your satisfaction with a modeler, then the modeler isn't doing its job. The first two modelers I used fell into this category, and I did not keep them. The modelers I've used since 2007 have all taken care of the issue to my satisfaction.

 

[ragingplatypi]

I’m realizing that I’m actually how illiterate I am with power amps (just like actually playing). I know what sounds good and can slowly analyze it after the fact, but can barely translate from the page. Same thing with EQ (I actually keep a printout of an eq curve in my gigbag to reference when I’m editing).

 

[jellodog]

@jay mitchell Do you have a current favourite neutral SS power amp that you would recommend to be used with a regular guitar cab?

I have a couple of options that I'm currently enjoying, but I'm always interested in improving on what I've got. I'm curious because of your level of interest in this subject and depth of expertise.

My power requirements are modest - I don't play very loud. And like everybody else, I'm just looking for low THD and extremely flat.

 

[dk_ace]

Another piece of information that doesn't translate directly to modelers is dual master volume amps.
Modelers typically model only ONE of the volumes and bypass (on 10) the other.

Friedman BE100 Deluxe, has a Channel and a Global volume, that's two Log pots that attenuate the volume.
Mesa Boogie Rectifier has Master volume per channel and global Output volume, that's also two log pots one after the other.
Diezel VH4.
Marshall JVM410
etc.

Some math to translate it to your modeler (assuming all volume pots are logarithmic).
Let's say you have both the Channel and Master at 5 (12:00 o'clock), that's 10% output voltage after each pot.
Thus: 10%*10% = 1%, and 1% the voltage will be around 1 (8 o'clock) on a single Master volume amp Like JCM800 or SLO100.


View attachment 508



A quick test to hear when the modeled poweramp in a Full Amp model starts to compress/distort is to set Treble and Presence on 10 and slowly raise Master from 0 up until you hear a change in sound, typically around 2 with Helix models.
Mind that on a real single master volume amp like a SLO100, 2 (9 o'clock) is already inhumanly loud.

Now you know where my suggested setting of "Master on 1" comes from, it is the equivalent of dual master volume amp on 5 and 5, which is super loud even in a club.

I don’t think you can predict the results the way you’re describing here. Neither fractal nor L6 model the taper of the master volume pot, they both just set it to something like they the taper of instead of obsessing about the real amps taper. Therefore, you’re better off just setting it by sound and feel.

For me, I set NMV amps at 10 and MV amps I turn them up until I like what it’s doing. There’s generally a point where you can hear and feel it “wake up” a little and get fuller sounding. I generally go around that point and maybe back it off a touch. YMMV.

D

 

[la szum]

I had a Sampson 120... pretty anemic (55w per channel 8ohm) and doesn't work well with stage monitors. Would probably be ok for unpowered near field studio monitors which is what I think it's designed for.

Someone on the Fractal forum was gonna do the same with a different brand. I tried to warn them (based on
my own experience), but per Fractal forum rules all replies were deemed insufficient and irrelevant.

 

[James Freeman]

Neither fractal nor L6 model the taper of the master volume pot, they both just set it to something like they the taper of instead of obsessing about the real amps taper.

I think Line 6 models all the pot tapers and tolerance from the real amps, that includes volumes, tone stacks, presence, resonance.
When they model an amp they literally measure everything, as Ben said many times each amp takes months and moths to model.

Some rare insight from Ben:

I just looked and the Lead and Mega model files. At 1.25 (out of 10) the Lead channel master volume cuts by -33 dB and the Mega channel cuts by -45 dB. That was just based on the differences of taper from the two physical volume pots. Strangely, at a setting of 5 the Lead amp cuts by -13 dB and the Mega amp cuts by -15dB. In this case, there is a level difference, and it would happen in the real amp due to parts tolerances.

The full amp difference is a parts tolerance issue in the full amp. Comparing the master volume knob in the Lead model vs. the Mega model is NOT comparing the physical same knob. If a user wants to flip/flop between these two channel, just set the master to whatever value sounds best for a tonal response and then use the model's channel volume to level between the two.

Source:

Line6 Helix

For the Helix Native users - any of you use a pedal of any sort to, say, control a crybaby or some other parameter? If so, how? I've seen midi/usb pedals, could you connect one to your interface or computer and go from there? Typically my DAW (Studio One) is very easy about such things -...

www.thegearpage.net

The "Master on 1" is not a rule I permanently follow, I do check when the amp starts to squish and set it accordingly, of course I use my ears too.
Most high gain models start to compress at around 2 and in some cases 4 depending on how they modeled the master volume and if the original amp had more than one volume (channel -> master), also pot tapers, etc.

 

[James Freeman]

I pour Katana sauce all over my Helix tones and it sounds and feels great. Cue the gagging sounds

 

[Justincase]

I pour Katana sauce all over my Helix tones and it sounds and feels great. Cue the gagging sounds

Sweet Baby Ray says right on the bottle "The sauce is the boss"

 

[Boudoir Guitar]

I think Line 6 models all the pot tapers and tolerance from the real amps, that includes volumes, tone stacks, presence, resonance.
When they model an amp they literally measure everything, as Ben said many times each amp takes months and moths to model.

Some rare insight from Ben:


Source:

Line6 Helix

For the Helix Native users - any of you use a pedal of any sort to, say, control a crybaby or some other parameter? If so, how? I've seen midi/usb pedals, could you connect one to your interface or computer and go from there? Typically my DAW (Studio One) is very easy about such things -...

www.thegearpage.net

The "Master on 1" is not a rule I permanently follow, I do check when the amp starts to squish and set it accordingly, of course I use my ears too.
Most high gain models start to compress at around 2 and in some cases 4 depending on how they modeled the master volume and if the original amp had more than one volume (channel -> master), also pot tapers, etc.

How do they model the tolerances? Everytime you pull up a model the tapers are different, but fall somewhere within +/- 20%?!?

 

[James Freeman]

How do they model the tolerances?

What do you mean model tolerance? When they measure the real pots it includes all the tolerance differences of these specific pots.

If I would have to make an educated guess I would say that they measure several points across the pot travel range (say 0-10, so at least 11 points) and interpolate between them once they have the data.

You can see a paper cut guide on Volume 1&2 during modeling, just use your imagination as to why it's there.

 

[dk_ace]

I think Line 6 models all the pot tapers and tolerance from the real amps, that includes volumes, tone stacks, presence, resonance.
When they model an amp they literally measure everything, as Ben said many times each amp takes months and moths to model.

Some rare insight from Ben:


Source:

Line6 Helix

For the Helix Native users - any of you use a pedal of any sort to, say, control a crybaby or some other parameter? If so, how? I've seen midi/usb pedals, could you connect one to your interface or computer and go from there? Typically my DAW (Studio One) is very easy about such things -...

www.thegearpage.net

The "Master on 1" is not a rule I permanently follow, I do check when the amp starts to squish and set it accordingly, of course I use my ears too.
Most high gain models start to compress at around 2 and in some cases 4 depending on how they modeled the master volume and if the original amp had more than one volume (channel -> master), also pot tapers, etc.

I was wrong. L6 apparently does. The bit I was remembering and mixing up is that they have a volume compensation after amp model so that the volume change isn’t too drastic as you adjust the master volume control.

D

 

[Boudoir Guitar]

What do you mean model tolerance? When they measure the real pots it includes all the tolerance differences of these specific pots.

If I would have to make an educated guess I would say that they measure several points across the pot travel range (say 0-10, so at least 11 points) and interpolate between them once they have the data.

You can see a paper cut guide on Volume 1&2 during modeling, just use your imagination as to why it's there.

I was joking. You said they model the "tapers and tolerances". The specific pot has a specific value/taper. The tolerance just gives you an idea of how far off that specific value/taper may be from the nominal values. And this doesn't even get into age-related changes in value.

On the one hand, the Fractal wiki and the cataloged words of the guys from Line6 can be somewhat useful in terms of figuring out what's going on in different models.

On the other, those same resources are really good at sending folks down hours long rabbit holes that lead to no better results than just using a general understanding of how certain amps are traditionally used and/or designed to be used.

 

[TubeStack]

While I haven't tried it in a long time, I've really disliked any modeler (FM3, Stomp) into the effects return of my Electra Dyne. Sounded muffled and weird and just made me want to play the actual amp (although I didn't spend a lot of time tweaking it). And, if I'm going to bring a big tube head somwhere, I'm going to use it as the amp it is, and the modeller only for effects.

I have actually really enjoyed my Stomp into the Power Amp In on my Katana 100 MkII head with a Lone Star 2x12. Albeit this was at home at “loud TV levels“ and not band volume. Going to try the same with the FM Turbo when it gets here later this week. :). If I like it enough, I may pick up the PowerStage 700 and try it…

So to follow up on this, I've now got the FM9T and have been getting really good sounding/feeling results using either the IIc+ or FAS Rhythm models, again with the Power Amp In on my Mk II Katana 100 head and my Lone Star 2x12. I've got the Katana in 100W mode and the Volume knob around 10 o'clock.

I'm VERY new to this, but the whole SS PA into a real cab thing has greatly increased the enjoyment factor for me with modelers. Sounds and feels way more inspiring to me than my "FRFR" experiments.

A few things that have helped make it even better with the FM9 (aside from the insanely great amp modelling): setting Speaker Thump, Drive, and Compression to '0' in the Speaker tab of the amp block and Compliance to 100%. Also, for some reason, the 4x12 C90 Impedance Curve sounds and feels better than the LS 2x12 one (I think it's called Tex Star 2x12 or something), even though the latter one would seem to better match the actual cab I'm using.

Anyway: question about “Katana sauce”: does the Mk II Power Amp In skip any power amp modelling/sauce and give you the straight Class AB power amp?

Thanks.

 

[Bob Zaod]

I'm not up on the technical aspects but I will say what has been working best for me going into the Power Amp In on my SpiderValve MKII 2x12 is setting the Helix out to instrument, diming the big knob on the Helix and then I mess with the master volume and channel volumes on my Helix amp blocks. I typically end up around 2.5-3 on master and 6 or so on channel to get to gig/rehearsal volumes. I get natural and musical feedback on my gain amps easily and yes it sounds fantastic.

 

[Alex Kenivel]

Anyway: question about “Katana sauce”: does the Mk II Power Amp In skip any power amp modelling/sauce and give you the straight Class AB power amp?

AFAICT there is no power amp modeling within the amp channels. I have some reservations about this "Katana Sauce" and believe people just don't like the speaker. The poweramp is very clean, although the effects return is a tad bit darker than the labeled Power Amp In

 

[Bob Zaod]

AFAICT there is no power amp modeling within the amp channels. I have some reservations about this "Katana Sauce" and believe people just don't like the speaker. The poweramp is very clean, although the effects return is a tad bit darker than the labeled Power Amp In

The only sauce I get with Katana is awesome sauce

 

[TubeStack]

AFAICT there is no power amp modeling within the amp channels. I have some reservations about this "Katana Sauce" and believe people just don't like the speaker. The poweramp is very clean, although the effects return is a tad bit darker than the labeled Power Amp In

Thanks.

Yes, there’s a helpful Katana superfan over at TGP ( @BenoA) who says that, when plugged into the Power Amp In, you can’t edit anything with desktop editor except for this:

 

[Alex Kenivel]

Thanks.

Yes, there’s a helpful Katana superfan over at TGP ( @BenoA) who says that, when plugged into the Power Amp In, you can’t edit anything with desktop editor except for this:

Yep, pretty limited. If you use the effects return instead you can tweak the response with EQ, which is what I do. I have the high shelf on the Parametric EQ and the 125hz slider from the Graphic EQ assigned to two panel knobs for some quick bass and treble cuts

 

[andergtr]

i have used the helix 4CM into my bogner ecstasy, and when switching between the helix amp models and the preamp section of the ecstasy, you don't hear that the modeler obviously sounds like a modeler.

in other words, yes...have a real guitar power amp section makes a huge difference. just make sure you aren't using a cab or IRs.