FM3 General Discussion Thread

UltraRes is 170 ms - This states that UltraRes IRs will be truncated (further)
According to Jay Mitchell, an expert in the field, you only need about 20ms to capture the actual cab. Everything after 20ms is room reflections, and you need far more than 170ms to capture the actual room, so really it’s just added noise. I personally feel I get better results using the “Normal” 20ms IR + one of the great reverbs. There was a thread or two on here, I believe started by Cliff, talking about some of the benefits of shorter IR. After a fair amount of personal experimentation I think it’s a non issue. YMMV
 
No smoothing and IR length on the FM3 is a big bummer for me since they’re very important for the IR’s I use in the iii. I was thinking about getting an FM3 to replace my iii, but probably not anymore.
 
No smoothing and IR length on the FM3 is a big bummer for me since they’re very important for the IR’s I use in the iii. I was thinking about getting an FM3 to replace my iii, but probably not anymore.
You always could process the Ir outside the fm3 with cab-lab or another 3er party software. Maybe that could work for you
 
According to Jay Mitchell, an expert in the field, you only need about 20ms to capture the actual cab. Everything after 20ms is room reflections, and you need far more than 170ms to capture the actual room, so really it’s just added noise. I personally feel I get better results using the “Normal” 20ms IR + one of the great reverbs. There was a thread or two on here, I believe started by Cliff, talking about some of the benefits of shorter IR. After a fair amount of personal experimentation I think it’s a non issue. YMMV
I believe I've read somewhere on here that more than 20ms is needed to capture bass frequencies in some cases, but not in most. It seems that the industry standard is 20ms.
 
According to Jay Mitchell, an expert in the field, you only need about 20ms to capture the actual cab. Everything after 20ms is room reflections, and you need far more than 170ms to capture the actual room, so really it’s just added noise. I personally feel I get better results using the “Normal” 20ms IR + one of the great reverbs. There was a thread or two on here, I believe started by Cliff, talking about some of the benefits of shorter IR. After a fair amount of personal experimentation I think it’s a non issue. YMMV
I believe it was Cliff, an expert in the field, arguing that you do benefit from longer IRs... :p https://wiki.fractalaudio.com/wiki/index.php?title=Impulse_responses_(IR)#Length That's probably matter of the taste, but I prefer to have a choice.

I understand that UltraRes is 170ms, so if this means FM3 truncates to 170ms, we're probably fine, I just want to make sure it doesn't cut more. It's not stated clearly.
 
The FM3 also includes the entire speaker cab impulse response (“IR”) collection from the Axe-Fx III, with a stunning 2,200+ “Factory” choices and 1,024 “User” locations to store custom sounds from free or commercial producers.

Keep in mind Fractal has included the entirety of the factory cab library from the Axe Fx 3. Sure the IRs might get truncated down but would Fractal allow it to get past a point where they feel it negatively impacts the sound? I doubt it. Again the differences may be noticeable but nothing to worry about. The FM3 will still sound killer.
 
If I chug with my Recto and 412 cab, the cab often rings out for a good quarter of a second. I don't know how you'd get that same effect with a 20ms IR. And if you use the one reverb slot for just that, then you lose any room ambience you might need to add. :oops:
 
So the FM3 main outputs are XLR ONLY. On the AX8 there were also unbalanced 1/4" jacks for Output 1. I am using a FRFR solid state power amp (Seymour Duncan Powerstage 170) into a GUITAR cabinet / speaker (V30). My power amp only accepts 1/4" input. I don't like using XLR to 1/4" cables because they are not readily available most places and I sometimes forget a cable when loading for a gig (I try not to, but inevitably it happens). So I was going to use Output 2 to connect to the power amp instead of Output 1 since I can then use standard 1/4" to 1/4" TS guitar cables. In the FM3, I will turn off the speakers cabs globally, copy Outoput 1 to Output 2, and sum the stereo output to mono.

Is there any disadvantage to using Output 2 instead of Output 1 in this scenario?
 
I believe it was Cliff, an expert in the field, arguing that you do benefit from longer IRs... :p https://wiki.fractalaudio.com/wiki/index.php?title=Impulse_responses_(IR)#Length That's probably matter of the taste, but I prefer to have a choice.

I understand that UltraRes is 170ms, so if this means FM3 truncates to 170ms, we're probably fine, I just want to make sure it doesn't cut more. It's not stated clearly.

Lately Cliff prefers shorter IRs. Read this (Nov 2019) https://forum.fractalaudio.com/threads/ir-length.155295/
 
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According to Jay Mitchell, an expert in the field, you only need about 20ms to capture the actual cab. Everything after 20ms is room reflections, and you need far more than 170ms to capture the actual room, so really it’s just added noise. I personally feel I get better results using the “Normal” 20ms IR + one of the great reverbs. There was a thread or two on here, I believe started by Cliff, talking about some of the benefits of shorter IR. After a fair amount of personal experimentation I think it’s a non issue. YMMV
And I just don't agree. I have often tested UltraRes IRs in normal mode and I always prefer UltraRes mode.

Edit: 20 ms may be enough to capture the sound of the speaker, but not the cab. Try hitting a 4*12 with a hammer and listen for is response - longer than 20 ms.
 
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Note IRs are not only cabs. There are classical and acoustic guitar IRs, which seem to fit nicely in 150ms. I haven't done much testing about it, but I'd prefer not to be forced to cut them earlier.
 
Note IRs are not only cabs. There are classical and acoustic guitar IRs, which seem to fit nicely in 150ms. I haven't done much testing about it, but I'd prefer not to be forced to cut them earlier.
Hmmm.... Hadn't thought of that application. I actually used acoustic instrument IRs regularly on the AX8, so I'm very curious how they would be affected.
 
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