Axe-Fx III Firmware Release Version 13.01

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Sup? ;-)

It's Back!!!! Nice fix on the Global Input gain. I would not have looked there.
I have been Jamming on a Engl Savage patch that I have been working on and stopped having to really tweak it in 12.11. It recorded great and felt right even through the next couple of updates and (I always load Betas too.)
Anyway,, I made a couple of copies of the patch to different patch slots to play around with the new drives. this patch has a drive in it, left over from tweaking it till I didn't need it, but I don't have it on now. So,,I guess after loading the beta, I'm still playing around with the other patches and come back to my main patch and hmmmm it don't seem like it has the balls it did,, shit,,, did I change something?...load up my backup from the computer,,same thing,, Shit,,,"DID"? i have the drive on..after I save the backup IDK...been a couple rev. since I saved it, and It's got balls when it's on,,but I swear it was off,, even in the backup it's off,,, I'm like WTF,,, oh well maybe I did, after awhile I just step away.

I See this today, and think damn..another update?,, cool. I read the release notes and it hits me.....I load it up...BAM!!!! It's BACK! Thanks Cliff,, I thought I was going stupid.... as something for me is set and forget,, "I" would not have bothered to look at the global Input gain. and figured I just jacked something up.

MOSHON
DAVE
 
2112 said:
These videos have a pretty good breakdown of why op-amp choice doesn't really matter in something like a tubescreamer.



Click to expand...

Actually op-amp choice does play a role. It's measurable. There are two characteristics of op-amps that affect the response: Gain-Bandwidth Product (GBW) and slew rate. The Axe-Fx III models both of these. Slew rate is exposed to the user. GBW is hard-coded.

As you turn the gain up the bandwidth is reduced because of the GBW. The LM308 as used in the Rat has particularly poor GBW and that is partially responsible for it's unique tone. The ua741 and LM1458 also have poor GBW and were a popular choice due to low cost. Also the GBW tends to decrease as the amplifier is run at lower voltages. GBW is typically specified at +/- 15V but most pedals effectively run at +/- 4.5V.

Slew rate is a similar phenomenon but is a large signal limitation. It's usually caused by the compensation capacitor. The op-amp can only provide so much current to the compensation capacitor. If the output signal is rising or falling at a high rate the amount of current needed to charge/discharge the compensation capacitor is greater than can be supplied.

A third factor is the clipping behavior. If driven by a strong enough signal the op-amp will also clip in a Tube Screamer design. Sometimes this clipping is slightly asymmetric. I can't really divulge any more about this because it's one of the secrets of modeling a drive pedal.
 
well i did the update las night and for the first time doing updates i get this message,see attached picture,i followed the scren intruccions and i press exit and now the axe 3 is sounding bad like with lot of bass,harsh sound,it never happen to me before with the firmware updates
 

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NightWalker said:
well i did the update las night and for the first time doing updates i get this message,see attached picture,i followed the scren intruccions and i press exit and now the axe 3 is sounding bad like with lot of bass,harsh sound,it never happen to me before with the firmware updates
Click to expand...
For some reason your factory cabs got erased. Contact support and they will walk you through re-installation.
 
FractalAudio said:
Actually op-amp choice does play a role. It's measurable. There are two characteristics of op-amps that affect the response: Gain-Bandwidth Product (GBW) and slew rate. The Axe-Fx III models both of these. Slew rate is exposed to the user. GBW is hard-coded.

As you turn the gain up the bandwidth is reduced because of the GBW. The LM308 as used in the Rat has particularly poor GBW and that is partially responsible for it's unique tone. The ua741 and LM1458 also have poor GBW and were a popular choice due to low cost. Also the GBW tends to decrease as the amplifier is run at lower voltages. GBW is typically specified at +/- 15V but most pedals effectively run at +/- 4.5V.

Slew rate is a similar phenomenon but is a large signal limitation. It's usually caused by the compensation capacitor. The op-amp can only provide so much current to the compensation capacitor. If the output signal is rising or falling at a high rate the amount of current needed to charge/discharge the compensation capacitor is greater than can be supplied.

A third factor is the clipping behavior. If driven by a strong enough signal the op-amp will also clip in a Tube Screamer design. Sometimes this clipping is slightly asymmetric. I can't really divulge any more about this because it's one of the secrets of modeling a drive pedal.
Click to expand...

More golden nuggets of wisdom! I really hope you release that drive pedal modeler you touted a little while ago.
 
FractalAudio said:
As you turn the gain up the bandwidth is reduced because of the GBW. The LM308 as used in the Rat has particularly poor GBW and that is partially responsible for it's unique tone. The ua741 and LM1458 also have poor GBW and were a popular choice due to low cost. Also the GBW tends to decrease as the amplifier is run at lower voltages. GBW is typically specified at +/- 15V but most pedals effectively run at +/- 4.5V.
Click to expand...

Regarding bandwidth/headroom/clipping characteristics for a drive pedal topology like the OCD, it can be run at 9-18 volts, and besides less abrupt clipping this seems to give more space and subtlety to the harmonics. It might be a psychoacoustic effect, but I'm wondering if changing the effective supply voltage of drives (~drive "variac"?) is something that makes sense as a way to control OD characteristics either for any drive model or something like the OCD. It might sound like crap (or not work) on some models but it might provide different sonic territory by scaling supply voltage up or down.

I imagine that adding more diodes (which we can already do) achieves similar ends but might be different than changing supply voltage.
 
yyz67 said:
Regarding bandwidth/headroom/clipping characteristics for a drive pedal topology like the OCD, it can be run at 9-18 volts, and besides less abrupt clipping this seems to give more space and subtlety to the harmonics. It might be a psychoacoustic effect, but I'm wondering if changing the effective supply voltage of drives (~drive "variac"?) is something that makes sense as a way to control OD characteristics either for any drive model or something like the OCD. It might sound like crap (or not work) on some models but it might provide different sonic territory by scaling supply voltage up or down.
Click to expand...
That's because the OCD has a gain of ~5 after the clipping diodes. If the diodes clip at 0.7V, say, then the output of the buffer is 3.5V which is right at the point where a typical op-amp will distort when run from 9V. Increasing the voltage will increase the headroom of the buffer stage and prevent it from clipping. IMO it's a bit of a design flaw. I would've reduced the gain of that stage slightly.
 
FractalAudio said:
That's because the OCD has a gain of ~5 after the clipping diodes. If the diodes clip at 0.7V, say, then the output of the buffer is 3.5V which is right at the point where a typical op-amp will distort when run from 9V. Increasing the voltage will increase the headroom of the buffer stage and prevent it from clipping. IMO it's a bit of a design flaw. I would've reduced the gain of that stage slightly.
Click to expand...
You know what might be cool... Is if you went through all of the Drive models and made some more 'FAS' versions, tweaked to what your idea of how you would have done it (like with the "FAS" Amp models). I know that there are a couple already, but a few more would be cool..
 
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Johnkenn said:
Sorry if this has already been answered...maybe this is just the way the Timmy pedals are set up...but I notice in the Austin Buddy presets that the Bass and Treble knobs on the Timmy drives is backwards. 1 is full bass, 10 is no bass...and same with treble. Maybe it's just because the AB presets haven't been updated?
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Yes, the Live Gold presets and Naked Amps were all created before Axe-Fx III Firmware 13.01. Amp sound are not affected, and most drives sound the same or better than I used and don't need adjustment. But yes, the Timmy drive was changed and controls reversed in new fw 13.x (for the better!).

It's an easy fix you can do on your own, and very very few of the Live Gold presets -- probably <10 out of 1000 scenes -- use the Timmy drive in channel D specifically as part of the tone design. I'm not in a hurry to do an TonePack update just because of that. And who knows what other goodness may be coming in firmware updates soon? :cool:
 
2112 said:
The headroom parameter is a really nice addition to the amp block - here's a quick little video demonstrating the effect MV has on the Recto 1 Orange Modern, with the headroom parameter providing visual feedback. Clips were normalised in post and the video is "unlisted" on YT so you'll need to access it from here.



Also, try an amp like the Atomica or BE set to a light crunch and boost it with the Compulsion Distortion (level 10, drive around 3, tone to taste) - it'll take you from a great rock rhythm tone to a fat, searing lead. Glorious!

Edit - Preset attached
Click to expand...


Hi! I do not speak English. Could you tell me where the headroom parameter control is? Thanks!
 
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