Axe-Fx III Firmware Version 5.08

Added IR Length parameter to individual IRs in Cabinet block. Shorter lengths can be used to remove room reflections and/or decrease CPU usage.

Question as to general impact on frequency response past a certain point, if anyone knows for sure. I imagine as IR length gets shorter, low frequencies (e.g. cab resonance) might be cut off more?
 
Question as to general impact on frequency response past a certain point, if anyone knows for sure. I imagine as IR length gets shorter, low frequencies (e.g. cab resonance) might be cut off more?
No. It's complicated. Some people claim you don't need any more than 20 ms. For many cabs this is true. It depends on the "formants". A guitar speaker is approximately "constant Q" and minimum phase. The peaks and dips are caused by formants and the Q of those formants is roughly constant. This means low frequencies take much longer to decay than high frequencies. I've measured some cabs with a low frequency formant that takes much longer than 20 ms to fully decay. This is the whole reason for Ultra-Res.

There are no absolutes. Many cabs can be captured just fine with 10-20 ms. Others need more. If you want some of the room in there then you need more. Try the different settings and use the one that sounds best to you.
 
Added Low Cut and High Cut to individual IRs in Cabinet block. Filter slopes are also selectable from 6 to 24 dB/oct.

I bought the Far Field IR pack yesterday and as I was trying a few different IR combinations earlier today I was literally wishing for this exact functionality. Thanks for the update!
 
Thanks for this new fw.
I've a littte question on my side: why have defaulted individuals ir high cut @2khz (and not 20khz) on existing presets that require editing all manually.?
edit: it's seems to occur only on cab's linked to a global block
 
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No. It's complicated. Some people claim you don't need any more than 20 ms. For many cabs this is true. It depends on the "formants". A guitar speaker is approximately "constant Q" and minimum phase. The peaks and dips are caused by formants and the Q of those formants is roughly constant. This means low frequencies take much longer to decay than high frequencies. I've measured some cabs with a low frequency formant that takes much longer than 20 ms to fully decay. This is the whole reason for Ultra-Res.

There are no absolutes. Many cabs can be captured just fine with 10-20 ms. Others need more. If you want some of the room in there then you need more. Try the different settings and use the one that sounds best to you.
Does the window lenght also change when shortening the IR lenght?
 
Do we need to reset amp blocks for this update? There is definitely a change in the tone for my gigging presets with 5.08. Like a cut in the high end. Sounds kind of muddy. I went back to 5.07 and everything sounded great again. Loaded 5.08 back up and it's like a blanket over the tone.
 
Do we need to reset amp blocks for this update? There is definitely a change in the tone for my gigging presets with 5.08. Like a cut in the high end. Sounds kind of muddy. I went back to 5.07 and everything sounded great again. Loaded 5.08 back up and it's like a blanket over the tone.
There were no changes to the modeling. If you are using Global Cab Blocks you will need to adjust the Low/High cuts.
 
Do we need to reset amp blocks for this update? There is definitely a change in the tone for my gigging presets with 5.08. Like a cut in the high end. Sounds kind of muddy. I went back to 5.07 and everything sounded great again. Loaded 5.08 back up and it's like a blanket over the tone.
Make sure the Low Cut/High cut and filter slopes in the Cab block have not changed.
"Added Low Cut and High Cut to individual IRs in Cabinet block. Filter slopes are also selectable from 6 to 24 dB/oct."
 
There were no changes to the modeling. If you are using Global Cab Blocks you will need to adjust the Low/High cuts.
Yep, I sure am.
So I've been using the Low/ High cuts in the Preamp section of the Cab block before this update set at 85/8500.
Should I leave those as is and just fine tune with the new ones added on the Cab page or set the ones on the Preamp page back to factory defaults (20/10k I believe?) and use the new ones on the Cab block page?
 
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Yep, I sure am.
So I've been using the Low/ High cuts in the Preamp section of the Cab block before this update set at 85/8500. Should
I leave those as is and just fine tune with the new ones added on the Cab page or set the ones on the Preamp page back to factory defaults (20/10k I believe?) and use the new ones on the Cab block page?
Leave the Preamp Low/High Cut as-is. Set the individual Low/High Cuts to 20 and 20K which defeats them.
 
Thanks for this Cliff ! The individual low cut/high cut is something I'll use a lot, been longing for those for quite some time

I like to use a slight boost before the hi cut in the Para EQ block, are one of the new slopes equivalent to that ? Are there any graphs showing the eq curve for each slope setting ?
 
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