VOX AC30 Model - Tone Cut Knob Emulation

pmella

Member
Hi Everyone,

I was searching for an answer to this question, but I could get it. Does anybody know how to emulate the tone cut knob that the AC30TB has? Is it the hiCut param?

Thanks in advance.
 
Also, AFAIK, the Vox AC30TB model in the AXE has been corrected by Cliff, and it will NOT behave or sound like the real AC30TB because of this. This correction was done by giving some mids to the model. This correction makes the model sound warmer and more bell-like than the real AC30, and it will take away the characteristic chime of the amp.
You can hear this on this video:



Both sound really similar, but you will notice than the AXE is warmer. This is due to those mids.

However, if you want to omit this correction, and regain the original behaviour and ear splitting chime of the AC30, simply set the Mid knod fully CCW. This will make it sound bright and chimey just like a real vox.

(I'm 99,99% sure that Axeman didn't know about this when he shot that video)

This is the thread Cliff talked about it:

http://forum.fractalaudio.com/axe-fx-ii-wish-list/61800-wish-top-boost-eq-section-works-like-real-thing.html#post768768

Also, Cliff, please correct me if I'm wrong. I was trying to figure out why Edo couldn't get the model to sound like his real AC30s, and I asked him if he had ever tried this before. He said he wasn't aware of this, and as far as he knew, the mid knob had to be kept at noon to keep it authentic. This may be the reason he could never get it to sound autentic?

P.D: Presence works as the Hi-Cut on this model.
 
Also, AFAIK, the Vox AC30TB model in the AXE has been corrected by Cliff, and it will NOT behave or sound like the real AC30TB because of this. This correction was done by giving some mids to the model. This correction makes the model sound warmer and more bell-like than the real AC30, and it will take away the characteristic chime of the amp.
You can hear this on this video:
Both sound really similar, but you will notice than the AXE is warmer. This is due to those mids.

However, if you want to omit this correction, and regain the original behaviour and ear splitting chime of the AC30, simply set the Mid knod fully CCW. This will make it sound bright and chimey just like a real vox.

(I'm 99,99% sure that Axeman didn't know about this when he shot that video)

This is the thread Cliff talked about it:

http://forum.fractalaudio.com/axe-fx-ii-wish-list/61800-wish-top-boost-eq-section-works-like-real-thing.html#post768768

Also, Cliff, please correct me if I'm wrong. I was trying to figure out why Edo couldn't get the model to sound like his real AC30s, and I asked him if he had ever tried this before. He said he wasn't aware of this, and as far as he knew, the mid knob had to be kept at noon to keep it authentic. This may be the reason he could never get it to sound autentic?

P.D: Presence works as the Hi-Cut on this model.

Sorry, but you are wrong. Please read that thread again.
 
Sorry, but you are wrong. Please read that thread again.

Thanks for your reply!

I understand that's how you limited the midrange notch to avoid that mid drop when the bass goes over a certain point.

So the mid knob at noon doesnt add any more mids than the knob at 0? IOW, the mid knob has no impact on the sound but rather on the behaviour?

Thanks!
 
Thanks for your reply!

I understand that's how you limited the midrange notch to avoid that mid drop when the bass goes over a certain point.

So the mid knob at noon doesnt add any more mids than the knob at 0? IOW, the mid knob has no impact on the sound but rather on the behaviour?

Thanks!

Read it again. You're still not quite getting it.
 
Let me explain it. The original request in that thread:
"The Top Boost tone stack has what I always assumed was a flaw, in the sense that when the bass control is set over about 9.5, the midrange 'notch' goes through the floor - drops by over 12dB."

Cliff explained that he "intentionally limited the midrange notch since, IMO, it's a design flaw in that tone stack" - but that "you can recover that behavior by setting the Mid control fully CCW".

In short: The AC30 models are absolutely accurate, except for that eccentric behaviour of the bass knob. When maxed it doesn't notch the mids like the original, because he "de-flawed" it... but if you want the sound of that midrange notch, just notch the midrange yourself. Whack it down and there you have it.
 
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So:
1. Original TB amps would notch the mids if bass knob was almost all the way up
2. That was a design flaw
3. Newer AC30s don't have that flaw
4. Axe FX version pretty much corrects that design flaw
5. If you still want to emulate that flaw, turn the bass way up and the mids fully down

That's what I think I'm reading in the linked thread?
 
So:
1. Original TB amps would notch the mids if bass knob was almost all the way up
2. That was a design flaw
3. Newer AC30s don't have that flaw
4. Axe FX version pretty much corrects that design flaw
5. If you still want to emulate that flaw, turn the bass way up and the mids fully down

That's what I think I'm reading in the linked thread?

#3. AC30's without the tone boost circuit don't have that flaw. (because they have a different tone circuit design)
 
Let me explain it. The original request in that thread:
"The Top Boost tone stack has what I always assumed was a flaw, in the sense that when the bass control is set over about 9.5, the midrange 'notch' goes through the floor - drops by over 12dB."

Cliff explained that he "intentionally limited the midrange notch since, IMO, it's a design flaw in that tone stack" - but that "you can recover that behavior by setting the Mid control fully CCW".

In short: The AC30 models are absolutely accurate, except for that eccentric behaviour OF THE BASS KNOB. When maxed it doesn't notch the mids like the original, because he "de-flawed" it... but if you want the sound of the midrange notch, just notch the midrange yourself.

Oh, thanks a lot!

I thought of the mid knob at noon acted as some sort of bass pot ground lift to fix the flaw, and turning it fully CCW would ground it again. Kinda like mids at noon: Corrected tone stack, Mids at 0: Authentic tone stack.

Thanks again for explaining this to me!
 
Oh, thanks a lot!

I thought of the mid knob at noon acted as some sort of bass pot ground lift to fix the flaw, and turning it fully CCW would ground it again. Kinda like mids at noon: Corrected tone stack, Mids at 0: Authentic tone stack.

Thanks again for explaining this to me!

Nope.

Mids at 5.0 authentic unless Bass > 9.5 in which case set Mid to 0.
 
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