Hell yes. Do you also use Guitarix?
Off topic, but: me too! Nice.
1 Like
Yes, of course!
Still struggling with presets. Do you use midi controls? Thinking about replacing my live rig for rehearsals, but didn’t set up my foot controller yet.
Tom
We should probably split this off into a separate topic, but I’ve been playing with a lot of free IRs available and doing graphic EQ (just for a slight cut around 500Hz) -> main block -> Tonestack -> Convolver with cab IR seems to work pretty well for me. I don’t use MIDI controls at all, just a bedroom noodler for now.
Done!
I’m nostalgic about my Linux days so will keep an eye on this 
Thanks, Tommo!
I find Ardour perfectly adequate for my needs, combined with a Scarlett Solo and Guitarix run as a separate application. With a few free IRs you can get pretty decent tones out of the latter.
Thanks, Tommo!
Good idea as I still have a long way to go to make Guitarix usable enough to take it from “late night at home noodling” to a rehearsal replacement for heavy gear.
so, @eric_divers, you would recommend a good Cab IR + a good room IR?
Any hints for good free sources? Found some online, anything you could recommend?
What is the latency you can get out of your system without or at least almost without xruns?
Will give the midi switching a try tonight.
Thomas
So I found this pack here after some Googling: www.osirisguitar.com/wp-content/uploads/7deadlysins%20Impulse%20Pack.zip
There’s a gazillion impulses in there, just fool around until you find something you like, ha.
I really liked the Bogner Ecstacy IR and the Engl 4x12 cabs. I’m using the latter right now, with this setup:
It doesn’t seem possible to use multiple Convolvers at once in Guitarix (if you’re using an amp sim as a plugin to Ardour that might be possible, but I’m lazy), so I just use a regular reverb to keep the sound from being too icepicky. Also, I’m on a ThinkpadE530 from like seven years ago, so I have to keep things simple.
Turning off your wifi keeps you from getting too many xruns. Seriously, it took me like an entire day to learn that trick.
These settings in JACK give me latency that my ears find acceptable, but YMMV:
11ms is about a hundredth of a second. I definitely can’t detect that, but again your ears may be better than mine 
I do this entirely by ear. I don’t really know what I’m doing, so whatever lets me practice and sounds remotely tolerable is A-OK by me, hah.
Things I have learned: diming the level on the TS model in Guitarix and then diming the preamp gain with low drive gives you some very strange behavior that my ears find pretty unpleasant. I’d rather use a bit more drive (which with my old tube amp I never did).
Cutting the 500Hz range a bit seems to compensate for the ugly “plastic” sound you can easily get at higher gain. This could be in my head. I think a friend of mine told me about this, I can’t recall (first cup of coffee right now).
I’ll try to record something representative of the best lead and rhythm tones I’ve gotten out of this setup and upload later.
(Edit: after re-reading what you posted I doubt this will help you much, you’re probably way ahead of me already. But maybe it’ll help some other poor schmuck down the line )
2 Likes
Thank you a thousand times, @eric_divers!
No, I’m surely not ahead of you. I just started using guitarix for practicing at home after finding it a bit decadent to turn on my orange od120 to practice at bedroom levels for 3 hours producing more or less just heat and a little sound (which isn’t too good at these levels anyway).
I didn’t even know about the convolver module in guitarix and checked it out this evening, very nice, although I just used it for reverb. Maybe I’ll check out the cab responses over the next days. The 500 Hz cut also improved the results quite a lot for whatever reason.
I also got the midi preset switching up and running. Works perfectly.
One problem I still have is, that the tube amp model produces an audible click when switching from my “heavy” sound to my clean sound. The convolver module producing the reverb makes it go through the roof, so this is not usable for live/rehearsal settings 
We’ll see what I can find out.
Theoratically it should be possible to combine two impulse responses to one file, but I have yet to find a way. This way a nice cab + reverb could be used in guitarix.
I get by with 8 ms latency at the moment. Your 11 ms equal approximately a cab to ear distance of 3,5 m. (Should be about 10 feet, don’t know where you come from).
Tom
2 Likes
So, my initial reaction to this is that you should be able to simply convolve the two files together, but and I’ve realized I think that’s not right. If you’re convolving signal A with signal B, and then convolving that with signal C, you should get… look, can we get LaTeX code support on this forum?
Hold on, nevermind, figured out a way using the dark sorcery of “screenshots” and “copy and paste.” I think it should be possible if you can convolve the amp and room sound together:
We don’t know f (the incoming signal) a priori, but we do know g (the cabinet IR) and h (the room sound) and those can be convolved first by… Wikipedia says Fubini’s Theorem, I say “lol, fukken calculus magic.” What I don’t understand is how you’d control how much room sound you get, because linearity of scalar multiplication means that if you were to just multiply the room sound by a constant that would pull out of the integrals and simply weaken your overall amplitude by that same factor. I’m drinking just enough to pull calculus out of my arse Wikipedia right now, but not enough to think too hard about that particular problem 
@tommo is an actual physicist rather than an Nth-year grad student, though, so perhaps he can point out something I missed 
Edit: I have once more realized you probably already knew this and this was just an exercise for a starved lockdown brain. Don’t mind me
3 Likes
yup - you can simply run the one impulse as a sound file - thru the convolver with the other impulse - the resulting output will be a combination of the two impulses. You can then use that in your convolver
2 Likes
Thanks! I’m glad my overblown pontificating wasn’t totally off the mark 
1 Like
No problem - I love the nerdy stuff!
One I forgot to mention - dry/wet levels?
so how do you control the reverb dry/wet level when combining this way?
Well the very first singular sample in the reverb file is effectively the Dry level - you can edit that to control the levels (or change the levels of all the other samples - which ever is easier!).
And the math operation is communicative - so it doesn’t matter which impulse order you process it in.
Have fun
2 Likes
Sick, thanks.
Oh okay the omega-equals-0 element tells you how much of the original signal is included, right? So do you need to normalize the whole thing when you’re done?
Yes that’s correct. And that applies for both impulses - the Cab IR and the Reverb IR. If you wanted to tweak the cab IR and bleed in a little of your raw signal - you can edit the very first sample.
Be aware though - I have many many Impulse files that are not trimmed correctly and sometimes don’t include the Zero dry mix sample. That’s because different software does it differently. Some convolvers do the dry/wet mix outside the convolution operation and have zero first sample. And sometimes a impulse will have a few samples delay before the zero sample comes along - hobbyist tweaking/creation I think?
say you wanted 50 percent reverb mix - you could make the first sample double it’s size - if it’s a zero dry mix sample, and then normalize the whole impulse. Or you could select all the other samples apart from the first and change the amplitude. Which ever is easiest.
Have fun!
1 Like
Yes, I had a suspicion that the theory looks somewhat like this. I just have to find a way to do it with the software tools I have.
But thank you both, what you already discussed here is amazing, maybe we can share some of the combinations here.
And I’m sure that combined IRs will save some computation time for guitarix. Also using an older Notebook (Lenovo T420)
Thomas
I think I usually want a 100% wet level for the cab IR but of course just about 10% for the reverb.
So I convolve the Cab IR with the Room IR with a full peaked 1st sample and the rest gained to 10% of the initial sound file (assuming it was normalized) , right?
I think I have to do it this way, because mixing dry/wet afterwards is impossible, because the pre cab dry signal will creep in. Will give that a try.
Thomas
Yes - that’s all spot on!