Impulse convolver/guitarix

[autostatic]

AutoStatic, what IR files are you using??

The ones brummer recommends in Dave Phillips' article.
Exit my girlfriend's Pocket Pod. Together with Rakarrack Guitarix is a killer app.

[funkmuscle]

Hey funkmuscle could you share your IR files collection? I'm feeling lazy clicking and trying random links.

hey morko, I can't post the individual IR files up but I looked at these link on this site for anything saying cabinet speakers, guitar amp, etc... anything to do with guitar.
http://www.kvraudio.com/forum/printview ... 58&start=0

the best ones came from here:
http://www.guitarampmodeling.com/viewfo ... 7afad11741

[Chipfryer]

I'll be upgrading my system soon so hopefully I'll get a shot at trying this hopefully. Not getting JaMin to work was a real letdown for me but never mind its all a learning curve isn't it.
Cheers folks.

[brummer]

Hi

Some news from SVN

I have add a new tube today, based on the algorithm from swh ladspa valve plugin (Steve Harrison), it act as post processing plugin after the effect chain, and new, a flanger plugin.
Also new is a BiQuad filter witch simulate the impulse answer of a fender amp (by adegert).

adegert have also add a experimental effect cain, witch include a additional new tube model and a new (zita-resampler based) up/downsample unit. To use them, you need to configure guitarix with the

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--debug --experimental

flags.
Then you could open the Experimental widget, witch provide the controls, over the menu "Engine -> Experimental"

Please let us know, if you check out the new units, what you think about.

greats brummer

[funkmuscle]

brummer, I'm liking it... only thing is my old presets lost their tone...

I noticed now in qjackctl that you don't see jconvolver, only guitarix.. is that right?

also notice that guitarix sounds great without IR files which brings up a question. Guitarix now runs like my digitech RP90 pedal in which it sounds great with it's amp sim but the amp sim can be bypassed to use IR files(you know what I mean? one setting for direct to amplifier and a setting for mixer connection.)

I'm wondering if guitarix natural amp sound can be bypassed so it acts as a preamp? you know the sound? just that tinny sound like plugging a distortion pedal to the sound card...that sounds very thing until you route the distortion pedal-->soundard-->jc_gui then that pedal now sounds like an amp and with different IR files, many different amps.
I hope I'm not confusing you here...

[brummer]

brummer, I'm liking it... only thing is my old presets lost their tone...

Therefore only two reasons possible,
1.) when you have enable the --experimental flag and use oversample, for now you must make sure that you set the oversample level in the Experimental widget to 2. That will fixed next time.
2.) The new effects didn't switch the state when you switch a preset, you must disable them per hand after change a preset and save the preset again with the settings for the new effects included to avoid that.

I noticed now in qjackctl that you don't see jconvolver, only guitarix.. is that right?

.
Yes, the convolution engine is included in the guitarix engine, no extra ports needed.

also notice that guitarix sounds great without IR files which brings up a question. Guitarix now runs like my digitech RP90 pedal in which it sounds great with it's amp sim but the amp sim can be bypassed to use IR files(you know what I mean? one setting for direct to amplifier and a setting for mixer connection.)

Didn't understand you here, , you can bypass guitarix engine, (press "b"), but that mean that the input simply copy to the output, without processing the guitarix engine (include the convolution engine).
That could surly change to bypass guitarix engine and process convolution engine only, is it that what you mean ?

[funkmuscle]

Didn't understand you here, , you can bypass guitarix engine, (press "b"), but that mean that the input simply copy to the output, without processing the guitarix engine (include the convolution engine).
That could surly change to bypass guitarix engine and process convolution engine only, is it that what you mean ?

I knew it was confusing ... Let me try again.

The guitarix sound engine is a complete amp like any real amp. It has preamp, different voicing(the amp choices) power amp and it's own cabinet simulator.
IR files are optional.
I don't want to bypass the sound engine, just guitarix's built in cabinet simulator.

In other words, the bypass would be there to let guitarix act like an amp head so the IR files which are cab sims will complete it.
look at this link as an example:
http://www.ndzeit.org/guitar/dirthead.html
because this vst reminds me of guitarix. It has it's own preamp, power amp and cab section when the "Cabinet" button is active and when it's not, you only get the vst preamp section so you can now connect to IR files to complete the sound and also get different sounds.

EDIT:
actually, this may explain it here... this is how they explain it at a site where I first learned about IR files.
the following I copied from that site to explain it to you.:

Ok, how to use them?

If your amp-sim does not support an external impulses loader, you'll need a DAW (Cubase, Reaper, Sonar, etc...).
Load your ampsim and BYPASS THE CAB (this is IMPORTANT).

How to bypass the cab?
Guitar Rig: just CLOSE the cab (or matched cab) module. I mean CLOSE, not switch off! This is IMPORTANT. GR cab-sims even if switched off, do change the eq! So, you HAVE TO CLOSE IT WITH THE "X" BUTTON.
Amplitube 2: go into the cab section and activate the BYPASS switch you see in the upper right corner.
Wagner Sharp: you don't need to do anything. Wagner doesn't have a cab emulation.
Dirthead 0.6/0.8: switch off the "CABINET" button on the right of the interface.
BTE Juicy77: select "cabinet disengage" or something like that in the lower bar of the interface.
Simulanalog JCM900: you CAN'T bypass the cab... I know, that's bad...

Now, if you have bypassed the cab correctly, when you play a distorted preset you'll hear a total shitty sound, fizzy as hell, no bass, harsh... it's ok, you're hearing how an amp sounds like without a cab.

[brummer]

The guitarix sound engine is a complete amp like any real amp. It has preamp, different voicing(the amp choices) power amp and it's own cabinet simulator.
IR files are optional.
I don't want to bypass the sound engine, just guitarix's built in cabinet simulator.

But guitarix didn't have a built in cabinet simulator.
The only cabinet simulation could set in the high/lowpass and high/lowcut part in the disstortion unit and with the parametric EQ's , when you know how to set it.
http://www.hexeguitar.com/diy-cabsims_e
Indeed, there is a buildin high/lowpass with fixed values (130/5000) in tube2 witch is in fact a dirty speaker simulation for a 12' speaker. This on can't disabled, because it's important for the tube sound here.

The different voicing(the amp choices), are a convolution filter witch is feed with different impulse response values(filter kernel) from different amp's, witch I have strip down to a range of 42 samples. This convolution filter do a time domain convolution, were Fons zita-convolver do a frequency domain convolution.
Time domain convolution is the choice for small kernel filters, here 42 samples. With bigger kernel filters you need to do the convolution in frequency domain, that's were zita-convolver is made for.

Anyway, the filter kernel's we use here, included the cap simulation already, so there is no way to disable them, without dissable the hole amp choice, or work out other filter kernels without the cab part.

To close or switch of, in guitarix, when you switch of a unit, it is of, indeed of, no influence any more then, they are bypassed then.

So, when you switch of tube2, the EQ's, low/highpass-cut section in the disstortion unit and the amp choise, then you get a sound without a cab simulation.

[brummer]

Hi

Have add the new upsample mode to the main widget, you could select the upsample mode (1x - 8x) now.
Note that upsampling will increase the CPU usage a lot (8x ~= 50% CPU), but it is it worse, special for distortion you can get new levels now(recommended levels are 2x - 4x).

Thanks to adegert we use Fons zita-resampler for that, I have add a new configure option,

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--includeresampler

to build guitarix with the local included version of zita-resampler, for now, please use this flag (recommended).

It's also possible now to build guitarix with zita-convolver included as a object file, use

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--includeconvolver

for that, if you wish.

so far, have fun
brummer

[brummer]

ups, have just notice a error in my includition of the upsample function, (lowbandcutaway ), have fix it in re@685

[funkmuscle]

will try over the weekend and give feedback

[funkmuscle]

best sounding yet....love it!!!!

[brummer]

Hi

I have play around with optimization flags for the g++ compiler the last days, and found some useful flags to reduce the CPU usage from guitarix. Therefore I have add a new configure flag

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--optimization

When use this flag, waf will check the architecture and the compiler for witch of the flags could be used.
Note that --optimization will have no effect, when the --experimental flag is in use.
Also new is, the

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--faust-float

flag, I switched to double precision as default now, to build with single precision, use --faust-float.

Please let me know if you found some trouble with the optimization flag enabled.

greats brummer

[GarryO]

Hi, Hermann.
I getting a build fail with the --optimization switch in svn689 (svn688 built ok )

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GUITARIX 0.09.0svn

CPU version                              : AMD Sempron(tm) 2800 
C++ flags                                : -Wall -std=c++0x -O3 -DNDEBUG -march=                                                                      
K6 -mmmx -m3dnow -msse -mfpmath=sse -fomit-frame-pointer -ftree-loop-linear -ffi                                                                      
nite-math-only -fno-math-errno -fno-signed-zeros -fstrength-reduce -pipe 
Use faust                                : no 
Use faust precision                      : double 
Use internal zita-resampler              : yes 
Use internal zita-convolver              : no 
Experimental Extensions                  : no 
Install prefix                           : /usr/local 
Install binary                           : /usr/local/bin 
Install ladspa                           : /usr/local/lib/ladspa 
Guitarix style directory                 : /usr/local/share/guitarix/skins 
Guitarix builder directory               : /usr/local/share/guitarix/builder 
Guitarix pixmaps directory               : /usr/local/share/pixmaps 

'configure' finished successfully (2.156s)
Waf: Entering directory `/home/g/guitarix-svn689/build'
[ 1/43] cxx: ladspa/crybaby.cpp -> build/default/ladspa/crybaby_1.o
../ladspa/crybaby.cpp:1: error: bad value (K6) for -march= switch
../ladspa/crybaby.cpp:1: error: bad value (K6) for -mtune= switch
Waf: Leaving directory `/home/g/guitarix-svn689/build'
Build failed
 -> task failed (err #1): 
        {task: cxx crybaby.cpp -> crybaby_1.o}

regards ~g

[brummer]

Hi Garry

Thanks for report back, okay so a Semperon isn't a K6 ,

Let me know please if rev@690 builds okay ?
And interesting for me is also if you get a better performance
(less CPU usage) with the --optimization flag enabled or not ?

greats brummer