Guitarix: Tubes, Amp Impulses, overall usability

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sysrqer
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by sysrqer »

uns4ph3 wrote:
Thu Nov 12, 2020 12:41 am
They show up in my lv2 list as "Gx{name}" - the Tonestack just shows up as Amplifier.

Do you have Carla to try my preset? It should go a long way towards helping you answer this and get a usable tone. You'll need to load your own IRs in the signal chain (I recommend LSP Impulse Reverb for this since you can load more IRs and configure them a little more granularly than it's other Impulse plugin).
I tried your preset but have not added any IRs yet. What do you recommend?

This is an interesting thread. I always find guitarix a bit baffling because I know next to nothing about amps, just used to plug into a combo amp and play, so I never really know what to use or in what order.

merlyn
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by merlyn »

robin wrote:If that tells me anything, than that this preset was made using a much lower input signal which needed to be gained up hard to even trigger the compressor.
Or your input level is too high for this preset. High output humbuckers by any chance? :) clean_clean does not have extreme clipping here.
robin wrote:I think it's a bad design choice to name-drop and build the whole software around the tube types while not nearly replicating their real behaviour. It really makes it feel like a toy at first sight for people who use different tube amps on a regular basis.
I don't agree with this at all.
robin wrote:It gave me good sounds after 10 minutes of playing around ...
Guitarix will take more than ten minutes to get to grips with.

uns4ph3
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by uns4ph3 »

sysrqer wrote:
Thu Nov 12, 2020 3:43 pm
I tried your preset but have not added any IRs yet. What do you recommend?
For IRs I recommend the Ownhammer paid IRs but there are tons of free ones out there if you don't want to pay for theirs.

Signal chain wise, this is what I use.
- tuner
- noise gate
- optional: preamp. I have added this since i posted that preset to Dropbox. Good for gain control on the input signal
- distortion pedals for higher gain setups
- amp
- EQ
- Chorus/flanger/phaser
- impulse response
- reverb
- delay

robin
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by robin »

merlyn wrote:Or your input level is too high for this preset. High output humbuckers by any chance?
Not really, standard JB4s while testing. Shouldn't make a difference anyway if using Hi-Z input. My input level is about -20 to -5dB depending on playstyle and guitar (I don't use active pickups), so no danger there. Since I always record the dry signal to have reamping options I can tell you this preset clips, while other plugins do not, using the very same input signal. This preset seems to expect a line-in signal from an onboard sound card.
merlyn wrote:I don't agree with this at all.
That's perfectly fine, I don't hold the one and only truth, sadly :)
Do you disagree with it beeing a disgn-flaw, or that it' not close to the real deal?
Just for the latter case, I would like to back up my opinion and explain why it feels that way to me.
Many people describe tube sounds as "warm", so mostly but not exclusively budget modelers in the early days tried to avoid sounding digital by cutting out some high frequencies that came with the solid state or digital distortion. This compensation was overused by some very popular devices, so that became the new standard modeling sound. So not sounding digital was the holy grail, failing to see that lots of tube amps have that kind of digital sound to it natively. Therefore the technology was not achieving the professional breakthrough on a larger scale and ended beeing a beginners tool primarily. As I said, that was in the early days, modeling has come a long way to today's possibilities.
Especially the damping when increasing gain leads me to the conclusion that this is by design in guitarix, but that's not what tubes do in my experience. And that's why I think the plain Distortion is actually closer to a real sound than the "tube" emulation.

tramp
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by tramp »

Hi

Guitarix founder and maintainer here.

I've started this project back in 2008, at this time, computers wasn't as powerful then this day's, hence we chose a tube simulation which didn't overrun those old CPU's.
This day's, guitarix is widely spread, and changing the model will destroy the workflow of those who use it for long time.
Hence we are more in a maintainer mode with guitarix then doing actual development on it.
Still, that doesn't mean that the project is dead, but changes will only be picked wisely.

However, this day's, we've the LV2 plugin format on Linux and I focused more on doing some amp simulations as plugins then changing the model used in guitarix itself. As you noticed, you could easily bypass the guitarix amp and replace it with a Amp plugin load into the rack.

Here are some of my latest amp sims.
https://github.com/brummer10/XTinyTerror.lv2
https://github.com/brummer10/XDarkTerror.lv2
https://github.com/brummer10/FatFrog.lv2
https://github.com/brummer10/GxVBassPreAmp.lv2
https://github.com/brummer10/GxUVox720k.lv2
https://github.com/brummer10/GxSVT.lv2
https://github.com/brummer10/GxSupersonic.lv2
https://github.com/brummer10/GxPlexi.lv2
https://github.com/brummer10/GxMicroAmp.lv2
https://github.com/brummer10/GxCreamMachine.lv2
https://github.com/brummer10/GxBottleRocket.lv2
https://github.com/brummer10/GxBlueAmp.lv2
https://github.com/brummer10/GxFenderizer.lv2

maybe one of them suite you needs, maybe not, who knows.

regards
On the road again.

merlyn
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by merlyn »

A valve amp I like is a Fender Deluxe Reverb. If you only have ten minutes to spare to get a sound then this is the amp for you. The normal channel has three knobs -- volume, bass and treble. No drive, distortion or sparkle knobs. I have no idea why you think adding drive or distortion is going to get a Fender-y sound. :)
robin wrote:Shouldn't make a difference anyway if using Hi-Z input.
Hi-Z means high impedance. Z is the symbol for impedance in the same way R is the symbol for resistance. I'm sure you'd agree that there would be a difference in level between a telecaster plugged into a high Z input and a Les Paul plugged into the same input. Guitars need a high Z input because pickups have a high impedance. Otherwise there is 'tone-suck' which I'm sure you've heard about in marketing materials.

If you understand a bit of electronics marketing horseshit is less effective. Treble can be lost when there is an impedance mismatch -- this is why direct boxes are used when plugging a guitar or bass into the low impedance balanced input on a mixing desk. On the subject of technical terms used as marketing -- you mentioned 'class A' in a post above. Just out of curiosity what does class A mean to you?
My input level is about -20 to -5dB depending on playstyle and guitar (I don't use active pickups), so no danger there.
For recording with 24 bit -18dB is a good nominal level. Peaking signals quite high was relevant for analogue tape and 16 bit digital. 24 bit digital recording has a much bigger dynamic range so -18dB is good.
This preset seems to expect a line-in signal from an onboard sound card.
I'm not using the onboard sound.
Do you disagree with it beeing a disgn-flaw, or that it' not close to the real deal?
I disagree that it's "name dropping". tramp clarified that these are CPU efficient simulations.

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bluebell
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by bluebell »

tramp wrote:
Fri Nov 13, 2020 10:54 am
Hi

Guitarix founder and maintainer here.

I've started this project back in 2008, at this time, computers wasn't as powerful then this day's, hence we chose a tube simulation which didn't overrun those old CPU's.
This day's, guitarix is widely spread, and changing the model will destroy the workflow of those who use it for long time.
Hence we are more in a maintainer mode with guitarix then doing actual development on it.
Still, that doesn't mean that the project is dead, but changes will only be picked wisely.

However, this day's, we've the LV2 plugin format on Linux and I focused more on doing some amp simulations as plugins then changing the model used in guitarix itself. As you noticed, you could easily bypass the guitarix amp and replace it with a Amp plugin load into the rack.

Here are some of my latest amp sims.
https://github.com/brummer10/XTinyTerror.lv2
https://github.com/brummer10/XDarkTerror.lv2
https://github.com/brummer10/FatFrog.lv2
https://github.com/brummer10/GxVBassPreAmp.lv2
https://github.com/brummer10/GxUVox720k.lv2
https://github.com/brummer10/GxSVT.lv2
https://github.com/brummer10/GxSupersonic.lv2
https://github.com/brummer10/GxPlexi.lv2
https://github.com/brummer10/GxMicroAmp.lv2
https://github.com/brummer10/GxCreamMachine.lv2
https://github.com/brummer10/GxBottleRocket.lv2
https://github.com/brummer10/GxBlueAmp.lv2
https://github.com/brummer10/GxFenderizer.lv2

maybe one of them suite you needs, maybe not, who knows.

regards
Is there some documentation available which amps they simulate? Not everything is that obvious like Fenderizer.
Linux – MOTU UltraLite AVB – Qtractor – https://soundcloud.com/suedwestlicht

robin
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by robin »

@tramp Thanks for giving this insight, it makes things way clearer for me. I honestly didn't think about the fact that having a large userbase makes a conservative approach basically the only way to go. I'm definitively going to check your gits as soon as possible

@merlyn I'm not as deep into electronics as you seem to be (more of a math guy...), my basic interpretation was "high impedance - low current" which may well be incorrect or inaccurate. What I do know for sure is that I have a little knobby on my interface where I can level the input signal, which I would do if my input ever clipped or any other problems than "one specific preset in one specific software clips whithin its own signal chain" would occur. As I mentioned before I've used this setup for several years without any issues or anyone getting the recordings complaining. I would actually like to know how bitrate and desired peak correlate because I never heard of that, but that may be a little too OT, just as the question what types of sound one can create with an american tweed amp. I'm thinking about opening a thread about the bitrate-thing though, and hope for your reply if i do ;)

I think with tramps explanation the questions I had were almost completely answered, everything left to say is opinion (in my opinion).
To recap the questions real quick:
Tubes: CPU friendly but maybe not the most accurate simulation, based on a 2008 algorithm, widespread and accepted by many and therefore difficult to change
Amp Impulses: *googled, unverified* seems to be the output of the little known or at least not very prominent "specmatch" feature of guitarix, that Auto-EQs the sound to match a given recording by impulse response. Goes after the cab or instead of it, depending on how its made, independent of the tonestack if thats correct
Overall usability: Seems to work great for a lot of people, but I'm not one of them

@merlyn and @uns4ph3 Thank you for the lively discussion, I made interesting finds "en passant" and I'm looking forward to the next one :)

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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by tramp »

bluebell wrote:
Fri Nov 13, 2020 8:44 pm
Is there some documentation available which amps they simulate? Not everything is that obvious like Fenderizer.
Not that much, for some of them here is written which schematic inspired me for the simulation:
https://github.com/brummer10/GxPlugins.lv2#amplifiers

@robin
The Amp impulses been indeed the linear responses of some Amp's.
I use them mostly before the preamp.
Also, for clean sounds, you may try the BiQuad Filter before the Amp (instead a ampimpulse).
robin wrote:
Fri Nov 13, 2020 8:49 pm
Tubes: CPU friendly but maybe not the most accurate simulation, based on a 2008 algorithm, widespread and accepted by many and therefore difficult to change
We use this model: http://www.normankoren.com/Audio/Tubemo ... ticle.html
which is from 2003, but still used in many Ampsimulations this day's. Even the KPP one use it.
Just we striped it down to non linear response tables for every model instead calculate the response on every sample.
That may lead to a inaccuracy at some points, but measurements shows that the inaccuracy is below 1%.
Also, we use high/low pass filters around the models, which are needed to keep the response below the Nyquist-Frequenzy when roll in higher distortion levels, to avoid digital clipping.
That may disturb your experience with clean sounds. Using the BiQuad Filter before the Amp helps on that.

However, I long understand that Guitarix couldn't suite any Guitarist out there, and gladly we've alternatives on Linux this day's. :D
On the road again.

tramp
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by tramp »

So, this discussion has lead to some changes in guitarix.
It was decided to remove the high-pass filters we've had around the tube simulation to give more bottom end frequency's.
Also we removed some low/high-pass filters which was extra around the push-pull tubes.
And, we add volume controls (In/Output) for the power amp plugin, to give control over the added saturation from the power amp stages.
Discussion was here:
https://github.com/brummer10/guitarix/issues/22

@robin
as you was unsatisfied with the tube simulations, you may give guitarix a other try from our git repository.
On the road again.

robin
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by robin »

Woah, didn't expect that, I'd be honored to have taken part in improving guitarix :D
I'll definitively give it a shot soon!
By the way, I only had time to test some of your git projects so far but really liked the TinyTerror on a first glance :)

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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by Basslint »

I thinks this thread shows how great a project Guitarix is and how @tramp should be an example to all libre software developers.

I think the importance of Guitarix can only be understood by those who've been on GNU/Linux enough to see what was there before. And I am saying this as someone who kind of likes Rakarrack!

@tramp, if you think Guitarix is dragged down from legacy design decisions, why not release a major version and do away with the baggage? But I believe being able to run on older computer is still a selling point for Guitarix.
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tramp
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by tramp »

robin wrote:
Wed Nov 18, 2020 7:57 am
Woah, didn't expect that, I'd be honored to have taken part in improving guitarix :D
I'll definitively give it a shot soon!
Constructive critic is always welcome.
Basslint wrote:
Wed Nov 18, 2020 8:40 am
@tramp, if you think Guitarix is dragged down from legacy design decisions, why not release a major version and do away with the baggage?


Oh, I don't think so. There are no plans to drop guitarix.
On the road again.

Basslint
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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by Basslint »

tramp wrote:
Thu Nov 19, 2020 5:25 am
Oh, I don't think so. There are no plans to drop guitarix.
While this is certainly good news, as I am a long-time user, I wasn't talking about dropping Guitarix, I was talking moving to the next major version to introduce backward-incompatible changes if necessary and leave the current version in maintenance mode, moving the main development to the next version.

Also, Guitarix deserves a Wikipedia page, I wonder why nobody created one...
The community of believers was of one heart and mind, and no one claimed that any of his possessions was his own, but they had everything in common. [Acts 4:32]

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Re: Guitarix: Tubes, Amp Impulses, overall usability

Post by kirjis »

Hmm, now I have to build Guitarix from source, that filter removal is too important change for me to wait for packagers... :shock:
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