Creating Impulse Response (IR) files with Logic Pro 9 (Mac) for Axe II

Axeman

Axeman

Experienced
After reading many threads on IRs, I'm getting close to making my first one, but I'm confused on some points. Anyone out there with suggestions to my steps/questions below? Thx in advance!!!!

Here is what I've done so far (I may need to correct some things). I'm using Logic Pro 9 on Snow Leopard Mac Pro.

1) I was able to record a test tone. I used the tone oscillator in Logic. I triggered a 10 second sine wav that went from 20 to 20k hz over ten seconds.

2) I then added a particular plug in to the track that has a specific EQ curve that I want to use as an IR, and played the test tone on this track and recorded it onto another track. So now I have two .wav files in Logic which I exported as .wav files to my desktop. One file is the orig test tone and the other .wav file is the test tone that has been played through an EQ plug in (think of this as something similar to a custom reverb plugin).

3) I recorded them both at 48k and 24 bit, but I have to check if they were mono. I may have to redo this. What else do I have to look out for at this stage? One thing I don't understand is that the test tone is 10 sec and I'm reading the IR has to be very short or a specific size. I think the size goes down in a later step, no? How do I know if I've made a mistake at this point? Both .wav files seem to work (one is clean and the other is EQ'd).

4) So I was going to use Space Designer to deconvolve the two files, but Apple put this function in their Impulse Response Utility which I don't know how to use (I can't figure out how to load the two files into this utility). So I downloaded Voxengo Deconvolver for Windows (anyone have another alternative for this program for mac?) and ran it in Windows on Parallels. voxengo is easy to use and allows me to choose the base tone file and the tone file that I put through my EQ plugin. Voxengo worked and outputed a 37k .wave file. What I don't understand is how do I know I have the right size file at this stage? I saw posts saying the file had to be a certain size. Also, the Voxengo instructions suggested I bounce a small amount of silent space at the end of the EQ's tone file. I'm not sure if I have to bounce a particular size file or if later steps reduce it. My biggest issue is how do I know that Voxengo outputed the correct type and size of file?

5) Assuming I did previous steps correctly (I will redo them with if necesary), then I assume I can use the Axe-Fx IR converter to turn the .wav to a .sysex. Correct? Other suggestions? Does the Axe IR converter turn the IR file into the right size or do I have to manually do this in other steps?

I'm open to suggestions for programs that make this process easier.

Thx!!
 
Axe-Fx IR Converter

I came across another issue. I'm using the Axe-Fx IR Converter 2.0 downloaded from guitarlogic.org. I was able to load my .wav IR into the program. But I don't understand how to convert it into a sysex file. When I press "Save As..." it allows me to pick a folder and the file format says "Sysex Files (*.syx)" but the SAVE button is grayed out. It won't let me save the .wav IR into a sysex file. When I send it to the Axe-Fx (assuming the conversion is automatic during the send) the program crashes unexpectedly. My midi is working fine (I can send and receive presets over USB).

Anyone know how to use this converter. The waveforms look perfect in the program when I load a .wav file but I'l lost after this.

Thx!
 
I reported this to AlbertA some time ago but did not receive a response; I'm guessing that the problem is only on the Mac or he would have addressed it by now.

There are two ways I've found to work around the problem: use batch mode; or overwrite an existing .syx file. Or you could just use my utility. ;)
 
LMO said:
I reported this to AlbertA some time ago but did not receive a response; I'm guessing that the problem is only on the Mac or he would have addressed it by now.

There are two ways I've found to work around the problem: use batch mode; or overwrite an existing .syx file. Or you could just use my utility. ;)
Click to expand...

Thx LMO. I sent you a PM also. Where is your utility? Is your utility axomatic? I tried it and it created a sysex file that is 10.6kb in size. I sent it to the Axe but it didn't work. No sound and no name on the user 1 cab at bottom of screen. Green lights blinked during midi download. Maybe file is bad? The waveform looked good in Alberto's utility.
 
To import files into impulse response utility, they must be in AIFF format. All you need to do do then is drag 'n' drop.
 
antcarrier said:
To import files into impulse response utility, they must be in AIFF format. All you need to do do then is drag 'n' drop.
Click to expand...

Got it, thx. But it seems you can only drag one file into the screen. I need the program to take my original tone sweep file and then the file that is the tone sweep put through and EQ, and do the calc to turn the two files into an IR. In other words, I only want to use the IRU to do deconvolution. I dont want to use it to create the files or run the test tone. Other programs allow me to select the two files and it outputs an IR. There is no file open or select. I can drag the one file, but I need to do deconvolution on two files like in Voxengo Deconvolver.
 
You must log in or register to reply here.
Back
Top Bottom