Thoughts on FW 14 AST and other Clean-ish amps?

The new triode modeling is audibly more accurate when you compare it to the old algorithm. Especially at edge-of-breakup but also with regards to punch and overall dynamics. I did lots of testing and critical listening comparing just the preamp modeling with actual tube preamps. The new algorithm is so much better that I felt it was unwarranted to include a Global option to select the old algorithm. I could explain what is going on but I would be giving away some trade secrets.

I just tested the Deluxe Reverb again. I did my "double-blind" test where I randomize the A/B selection and then press the A/B switch to select between the amp and model and try to guess which is which. I failed and guessed that the model was the actual amp. I used to be able to pick things out that would give it away. Most notably that the model would sound more "direct", like the sound was coming off the face of the speakers whereas the real amp would sound like it was coming from around the speakers. V13 made a big difference in that and now with the new triode modeling I don't hear that difference anymore.
 
Most notably that the model would sound more "direct", like the sound was coming off the face of the speakers whereas the real amp would sound like it was coming from around the speakers. V13 made a big difference in that and now with the new triode modeling I don't hear that difference anymore.

That`s what i had criticque also here, and with FW14 a can`t reproduce it anymore. I´ve did a AB comparison some days ago with my Koch... but i did not hear the difference anymore. Axe is now in general superior to the Koch, although the Koch has it`s own "vibe" i really like...

Well done Cliff! :encouragement: We will do some AB comparison with some nice Tube Amps at the german Axe-Fest end of April, and i am really sure, we will match them now easily ... in sound & feel.
 
Parameters are never changed during a firmware upgrade, except when noted in the release notes.


Thanks for clarifying that Yek. I guess I sometimes overthink things and forget the obvious.

For the record, I've always stated that I love the AxeFX and I'm not knocking it, just curious to know where to look for answers. I'm really liking FW14, it is more punchy and dynamic for sure, and adjusting the gain parameters is no big deal.
 
I don't know about cleaner or not but I recorded my friend's Gretsch last night through the AST with the tremolo on and the tiniest bit of grit dialed in. His response was, "Wow!"

The break up was perfect and totally controllable with playing dynamics. I did notice at practice last week that I had to lower the gain on my main clean JTM45 jump patch last week, but it was more to dial back a bit of punch from the normal channel rather than reducing 'hair' or 'grit'.
 
I've just compared five of my reference amps with their models. Deluxe Reverb, Carr Rambler, Bandmaster, Princeton and Twin Reverb. The models are more accurate than ever. The only one that was off was the Bandmaster because the model assumes V1 has been removed and I had put V1 back in. Once I reduced the Master Volume to simulate putting V1 in the model was spot-on.

The breakup, pick response and response to rolling off the volume knob are so close that I cannot tell which is which when I do my blind A/B test.

Whether or not V14 is exactly the same as V13 I don't care. All I know is the models are uncannily accurate and sound great. When switching to the old modeling (which I can do in debug firmware) the pick response is not as accurate. It lacks power and punch and feels "congested" when picking lightly. It IS cleaner when picking lightly with the old modeling algorithm but it doesn't respond the same as the amps. The amps break up more when picking lightly. With the new modeling the breakup is the same when picking lightly.

FWIW my Deluxe Reverb is nearly impossible to get clean. With the volume on 2 it will still break up with my PRS (as will the model). Note that Fender amps are indicated from 1-10 whereas the Axe-Fx indicates from 0-10 so '2' on a Fender is approximately 1.1 on the Axe-Fx.

If we could step back in time.... oh... say 5-10 years and hear you say this (Heck, even 1 year) the guitar world would have to get pooper scoopers to pick their jaws up off the floor!

Sometimes I have to pinch myself knowing I have one of these incredible devices and even more so knowing that I have access to such a community of users and even the company that is creating and constantly improving this groundbreaking technology!

Amazing....

OK, time to poor another. :)
 
The new triode modeling is audibly more accurate when you compare it to the old algorithm. Especially at edge-of-breakup but also with regards to punch and overall dynamics. I did lots of testing and critical listening comparing just the preamp modeling with actual tube preamps. The new algorithm is so much better that I felt it was unwarranted to include a Global option to select the old algorithm. I could explain what is going on but I would be giving away some trade secrets.

I just tested the Deluxe Reverb again. I did my "double-blind" test where I randomize the A/B selection and then press the A/B switch to select between the amp and model and try to guess which is which. I failed and guessed that the model was the actual amp. I used to be able to pick things out that would give it away. Most notably that the model would sound more "direct", like the sound was coming off the face of the speakers whereas the real amp would sound like it was coming from around the speakers. V13 made a big difference in that and now with the new triode modeling I don't hear that difference anymore.

All I can say is:
1. On my rig with my guitars & my touch, v14 is easier to distort on several of these cleaner amps.
2. I understand there can be differences from one amp to another of the same kind. I also understand these amps are 40 +years older than when I used them & as all things do with age, they deteriorate to some extent. (unless all the parts have been replaced & then it's not a vintage amp anymore!)
3. I have never heard the amps Cliff used to model. ( I would love too!)
4. I have no reason to doubt Cliff when he says v14 is much more accurate.
5. v14 does sound great regardless of my concern.
6. I can make my peace with it, re-tweak & move on to more playing & less posting.:eagerness:
Even though I did not start this thread, the cleans are more important to me than the mid to high gain sounds so I had a very real concern. For me, this was never meant as a bash-fest on Cliff or Fractal & hopefully, it wasn't taken that way. (at least not by Cliff) Thanks for taking a look into this!
 
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Note that Fender amps are indicated from 1-10 whereas the Axe-Fx indicates from 0-10 so '2' on a Fender is approximately 1.1 on the Axe-Fx.
I just face-palmed myself for not realising this. Makes a big difference to the gain & also affects the tone controls. "3" on the dial is when a lot of Fenders can start to break up when hit a little harder, especially with HBs, which is a lot lower on the Axe:

Fender____Axe
__1______0.00
__2______1.11
__3______2.22
__4______3.33
__5______4.44
__6______5.56
__7______6.67
__8______7.78
__9______8.89
__10____10.00

Another reminder to "use your ears".
 
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Yes. It's a straight-line fit so use y = mx + b.

At 1 on a Fender it's 0 on the Axe-Fx therefore we can write 0 = m + b. At 10 on a Fender it's 10 on the Axe-Fx so we can write 10 = 10*m + b. Solving these two equations yields

m = -b
10 = 10*m - m
10 = 9*m
m = 10/9 = 1.11
b = -10/9 = -1.11

So, given the Fender knob value as 'x', the Axe-Fx equivalent value would be
y = 1.11 * x - 1.11.

You skipped 7 in you chart and things are off after '5'. Here is the corrected data:

Fender____Axe
__1______0.00
__2______1.11
__3______2.22
__4______3.33
__5______4.44
__6______5.55
__7______6.66
__8______7.78
__9______8.89
__10____10.00

Note that the pots used in guitar amps are notoriously poor tolerance and are "consumer" log taper. The Axe-Fx uses true log taper and the tolerance is perfect so there can be 10% or so mismatch at any given knob position.
 
Yeah, I did the calcs in Excel & when I copied it to the post the formatting got screwy & I must have accidentally deleted some points when trying to fix it manually. So my 6 was wrong & 7 was missing, the rest were Ok though.

Yep, good ole y = mx +b but made the Axe "x" & the Fender "y", so the 0 on the Axe was equal to b (i.e. 1) on the y axis for the Fender, with m = 9/10 i.e. 0.9, so:

y= 0.9x + 1, then solved for x:

x = (y-1)/0.9 = y/0.9 - 1/0.9 = 1.11x - 1.11
 
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Yes. It's a straight-line fit so use y = mx + b.

At 1 on a Fender it's 0 on the Axe-Fx therefore we can write 0 = m + b. At 10 on a Fender it's 10 on the Axe-Fx so we can write 10 = 10*m + b. Solving these two equations yields

m = -b
10 = 10*m - m
10 = 9*m
m = 10/9 = 1.11
b = -10/9 = -1.11

So, given the Fender knob value as 'x', the Axe-Fx equivalent value would be
y = 1.11 * x - 1.11.

You skipped 7 in you chart and things are off after '5'. Here is the corrected data:

Fender____Axe
__1______0.00
__2______1.11
__3______2.22
__4______3.33
__5______4.44
__6______5.55
__7______6.66
__8______7.78
__9______8.89
__10____10.00

Note that the pots used in guitar amps are notoriously poor tolerance and are "consumer" log taper. The Axe-Fx uses true log taper and the tolerance is perfect so there can be 10% or so mismatch at any given knob position.

This is great Cliff, and is exactly what I was originally asking, though I probably worded it poorly. Since the AST Volume is also "1-10", should we assume the same calculation?
 
One big positive out of this thread for me: it made me go explore this model, which I had skimmed over in previous FWs...

Good thing because after dropping the drive down to around 2, engaging the bright switch and bumping up the level it's right in my wheelhouse ;)
 
Only tiny comment on that

A e.g Vibro Champ would not work on Fender "1" needs min 1.5 to sound at all maybe that is due the high efficient Oxford speakers

Roland
 
Only tiny comment on that

A e.g Vibro Champ would not work on Fender "1" needs min 1.5 to sound at all maybe that is due the high efficient Oxford speakers

Roland

That's a very good point. My Atomic Jr behaves the same way; the dial goes from 0 to 11 but I typically don't get any sound until around 1-1.5 on the dial.
 
Yes. It's a straight-line fit so use y = mx + b.

At 1 on a Fender it's 0 on the Axe-Fx therefore we can write 0 = m + b. At 10 on a Fender it's 10 on the Axe-Fx so we can write 10 = 10*m + b. Solving these two equations yields

m = -b
10 = 10*m - m
10 = 9*m
m = 10/9 = 1.11
b = -10/9 = -1.11

So, given the Fender knob value as 'x', the Axe-Fx equivalent value would be
y = 1.11 * x - 1.11.

You skipped 7 in you chart and things are off after '5'. Here is the corrected data:

Fender____Axe
__1______0.00
__2______1.11
__3______2.22
__4______3.33
__5______4.44
__6______5.55
__7______6.66
__8______7.78
__9______8.89
__10____10.00

Note that the pots used in guitar amps are notoriously poor tolerance and are "consumer" log taper. The Axe-Fx uses true log taper and the tolerance is perfect so there can be 10% or so mismatch at any given knob position.

Maybe this should be added to the wiki ??
PM send to Yek.
 
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