Axe-Fx II "Quantum" Rev 9.01 Firmware Release

It seems my timeout and freeze last night may have indeed been a fluke. Been playing all night tonight while bouncing back and forth between the 5 or so patches I was goofing with last night when the crash happened. Been solid all night.

I also can't explain the difference coming from 8.02 to 9.01, but all of patches have improved. It seems pinch harmonics on the lower strings (especially on my 7) seem to react much better now and are clearer, sustain better. Thanks as always Cliff and team!
 
In the last few days, thanks to the discussion about using speaker comp when going thru a solid state power amp and cab, I've read a bit about how a speaker compresses and tried to understand what the new algo simulates exactly, taking into account the way Cliff described it.

Basically, if I got it right, since a tube amp has a relatively high output impedance it's very sensible to the load attached so every variation in the load impedance translates in a loss or gain of output power.
Being a vaper, I know that when a metallic wire is heaten its resistance (in this case impedance) rises according to the TCR (Temperature Coefficient of Resistance) of the material.
This probably also happens in the coil of a speaker and when it is connected to a tube amp this rise of impedance causes a loss of output power resulting in a compression of the signal.

The question is: does this also happen with a solid state power amp? The answer from what I understand is no, cuz it has a much lower output impedance so it's much less sensible to the load impedance and the loss of power is probably negligible. The same reason for which a solid state PA frequency response is not affected by the impedance curve of the speaker.

So the conclusion is that, even when using a SS power amp and a traditional cab, using the speaker comp is desirable, hence no need to have two amps and separate chains when using Frfr and pa+cab simultaneously.

Maybe there could be other causes of speaker compression like the difference of air pressure that arises when the cone moves inside a sealed enclosure, or friction between the moving parts of the speaker.. But these (if they exist at all), although likely in different amounts, probably happen in every tipe of speaker cabinet including FRFR, so no real need to simulate them.

Does this make sense to you?

Disclaimer: what I wrote above is just the result of my reasoning so it could be totally bullshit, if someone has more knowledge on the matter please chime in to correct me. :D
 
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In the last few days, thanks to the discussion about using speaker comp when going thru a solid state power amp and cab, I've read a bit about how a speaker compresses and tried to understand what the new algo simulates exactly, taking into account the way Cliff described it.

Basically, if I got it right, since a tube amp has a relatively high output impedance it's very sensible to the load attached so every variation in the load impedance translates in a loss or gain of output power.
Being a vaper, I know that when a metallic wire is heaten its resistance (in this case impedance) rises according to the TCR (Temperature Coefficient of Resistance) of the material.
This probably also happens in the coil of a speaker and when it is connected to a tube amp this rise of impedance causes a loss of output power resulting in a compression of the signal.

The question is: does this also happen with a solid state power amp? The answer from what I understand is no, cuz it has a much lower output impedance so it's much less sensible to the load impedance and the loss of power is probably negligible. The same reason for which a solid state PA frequency response is not affected by the impedance curve of the speaker.

So the conclusion is that, even when using a SS power amp and a traditional cab, using the speaker comp is desirable, hence no need to have two amps and separate chains when using Frfr and pa+cab simultaneously.

Maybe there could be other causes of speaker compression like the difference of air pressure that arises when the cone moves inside a sealed enclosure, or friction between the moving parts of the speaker.. But these (if they exist at all) probably happen in every tipe of speaker cabinet including FRFR, so no need to simulate them.

Does this make sense to you?

Disclaimer: what I wrote above is just the result of my reasoning so it could be totally bullshit, if someone has more knowledge on the matter please chime in to correct me. :D
+1

A definitive answer to this from Cliff would help a lot.
 
This might be a dumb question, but being relatively new to Fractal, I plead ignorance. Is 9.01 an official release or a beta? I'm asking because while it doesn't say it's a beta release, it's also not on the firmware download page. 9.0 is the most recent on the download page.
 
This might be a dumb question, but being relatively new to Fractal, I plead ignorance. Is 9.01 an official release or a beta? I'm asking because while it doesn't say it's a beta release, it's also not on the firmware download page. 9.0 is the most recent on the download page.

The download at the top of this thread is an official release of 9.01, not a BETA. Sometimes it takes a little time for the releases to make their way to the download page.
 
In the last few days, thanks to the discussion about using speaker comp when going thru a solid state power amp and cab, I've read a bit about how a speaker compresses and tried to understand what the new algo simulates exactly, taking into account the way Cliff described it.

Basically, if I got it right, since a tube amp has a relatively high output impedance it's very sensible to the load attached so every variation in the load impedance translates in a loss or gain of output power.
Being a vaper, I know that when a metallic wire is heaten its resistance (in this case impedance) rises according to the TCR (Temperature Coefficient of Resistance) of the material.
This probably also happens in the coil of a speaker and when it is connected to a tube amp this rise of impedance causes a loss of output power resulting in a compression of the signal.

The question is: does this also happen with a solid state power amp? The answer from what I understand is no, cuz it has a much lower output impedance so it's much less sensible to the load impedance and the loss of power is probably negligible. The same reason for which a solid state PA frequency response is not affected by the impedance curve of the speaker.

So the conclusion is that, even when using a SS power amp and a traditional cab, using the speaker comp is desirable, hence no need to have two amps and separate chains when using Frfr and pa+cab simultaneously.

Maybe there could be other causes of speaker compression like the difference of air pressure that arises when the cone moves inside a sealed enclosure, or friction between the moving parts of the speaker.. But these (if they exist at all), although likely in different amounts, probably happen in every tipe of speaker cabinet including FRFR, so no real need to simulate them.

Does this make sense to you?

Disclaimer: what I wrote above is just the result of my reasoning so it could be totally bullshit, if someone has more knowledge on the matter please chime in to correct me. :D


I don’t know if you were correct or not, however I do appreciate thinking through the issue on your part.

That being said, most amp models I’ve tried so far (being a “real cab user“) do not respond well to any amount of speaker drive above 1.5. Otherwise it sounds muddy and far too compressed. Assuring that you match volumes is important, otherwise Fletcher Munson may trick your ears.

I find that Usually setting speaker drive to zero is the clearest tone for me.
 
Hey just out of curiosity, did the latest firmware releases reset the noise gate settings? Or did something change with the input circuit? I have noticed considerable change in the noise floor pretty much across the board. I checked and it looks as though my noise gate settings have been reset to essentially off. I did do several install/re-install of firmwares, past and present and the noise floor change appears to be the same.

Just thought I'd check to see if anyone else had a similar experience.

Thanks!

edit: yeah there's definitely more input noise across the board. I was running several of the amps with no noise gate and now they have to be run with a noise gate to be useable. Strange behavior indeed. Maybe something changed with the 808 drive block tone circuit?

More investigating...
 
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Hey just out of curiosity, did the latest firmware releases reset the noise gate settings? Or did something change with the input circuit? I have noticed considerable change in the noise floor pretty much across the board. I checked and it looks as though my noise gate settings have been reset to essentially off. I did do several install/re-install of firmwares, past and present and the noise floor change appears to be the same.

Just thought I'd check to see if anyone else had a similar experience.

Thanks!

edit: yeah there's definitely more input noise across the board. I was running several of the amps with no noise gate and now they have to be run with a noise gate to be useable. Strange behavior indeed. Maybe something changed with the 808 drive block tone circuit?

More investigating...
I am experiencing the same issue with the Noise Floor, I checked my settings and they haven't changed, but the noise is considerably loud, as before I had practically none, utilizing the Input Noise Gate on high Gain settings of course. Anyone else with this issue...?
 
PS. I did not experience this with the 9.01 Beta 2 that I can remember, I will check again later tonight, by reloading both and checking the noise Floor.
 
I don’t know if you were correct or not, however I do appreciate thinking through the issue on your part.

That being said, most amp models I’ve tried so far (being a “real cab user“) do not respond well to any amount of speaker drive above 1.5. Otherwise it sounds muddy and far too compressed. Assuring that you match volumes is important, otherwise Fletcher Munson may trick your ears.

I find that Usually setting speaker drive to zero is the clearest tone for me.
And you're probably right (if you were talking about speaker comp).
Today I searched more on the matter and found a couple sources that seem more reliable:

https://www.google.it/url?sa=t&sour...XD40QFghRMAs&usg=AOvVaw0JnvXprRw-_dOASO533qN7

http://www.transcendentsound.com/Amplifier_Output_Impedance.html

What they say is that power compression happens regardless of the power amp type. Assuming a constant output voltage (like in solid state amps) from the amplifier, when the voice coil heats up its resistance increases and the watts decrease. For example when the coil reaches about 250°C the impedance essentially doubles and the power is cut in half and this results in compression.

In tube amps the same thing happens but there's something more going on: having an higher output impedance the output voltage is not constant but varies according to the load impedance (this is why the frequency response is affected by the impedance curve) and when the load increases the voltage across it increases too. This, from what I understand, translates in a (not so) slight power increase that partially counteracts the main power loss.
So, unless there's some other variable I don't know, a tube amp actually exhibits less speaker compression than a solid state one!

Anyway I think only an expert can give us the definitive answer, and probably @FractalAudio is the only one on this forum who can.

Regarding the original question, at this point I think the best practice (after the "use your ears" one) for those using a guitar cab would be to completely turn off speaker comp. This way, in terms of authenticity, you'd lose the "variable impedance curve part" of the simulation though.
Maybe the definitive solution (if it's doable) would be to separate this part from the "compression part" of the algorhythm and offer two independent controls?
 
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Hey just out of curiosity, did the latest firmware releases reset the noise gate settings? Or did something change with the input circuit? I have noticed considerable change in the noise floor pretty much across the board. I checked and it looks as though my noise gate settings have been reset to essentially off. I did do several install/re-install of firmwares, past and present and the noise floor change appears to be the same.

Just thought I'd check to see if anyone else had a similar experience.

Thanks!

edit: yeah there's definitely more input noise across the board. I was running several of the amps with no noise gate and now they have to be run with a noise gate to be useable. Strange behavior indeed. Maybe something changed with the 808 drive block tone circuit?

More investigating...
So something interesting happened when I was making a video to demonstrate the differing noise levels between the amp models. Basic layout, noise gate off, amp block, cab block, nothing else. I scrolled from the first amp on the first page giving 2 seconds each and when I reached BRIT AFS100 2, my axefx froze. So far it's totally unresponsive. Maybe there;s a bug in that amp model or maybe it's a shared Marshall model bug IDK just guessing, Cliffs the genius here so I cant say. However I did notice much higher noise floor on the 50W plexi models than I did on the 100W plexi models, and more on those than i did on the 800 models. Anyway just some observations. I'll post the vid when it's finished. Back to trying to unfreeze my axe....

update: power cycled my axefx and attempted to get the hang up to repeat but it did not hang. Cycled through all the amps without issue but still quite a bit of noise on some that I wouldn't expect and none on some I would (Dirty Shirley has very little noise floor vs 50 watt plexi hi 1 &2 has quite a bit more). More tracking......
 
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+1

A definitive answer to this from Cliff would help a lot.
+1
Ya, could be thermal resistance, but isn't there a harmonic 'compression' from the ballistics near the limits set by the spider and surround?
I imagine that would put a kink in the impedance and waveform. Whatever it does, I can't wait to try it.
 
here's a quick vid I did to document what I have going on. Just want to make sure this is newly normal behavior as I dont remember this being the case before I upgraded fw

Thanks!


Noise gate is off in your vid, when activated you still have the floor noise ?
 
Noise gate is off in your vid, when activated you still have the floor noise ?
Yes the noise gate works fine. I left it off in the vid to show the differences in noise floor I am experiencing with my unit after the fw update.
I primarily use the plexi models and the Freidmans (low gain) and haven't had to use the noise gate on them previously, but now they are not usable without the noise gate.
Like I said if my experience is the new normal, that's fine I just want to know if my experience is a shared one.

Thanks!
 
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