Who's using ACTIVE tone stack in their *high gain* models?

[Tubed to Life]

I messed around with this a couple weeks ago, but went back to passive as it seemed the interactivity of the tone controls made for more 'liveliness' in the tone and feel. Going to try again, though, cos I'm curious.

Anyone else using the active stack?....can you post a patch?

 

[luke]

Active tone circuits have positive and negative movement whereas passives only have negative. Having everything on 5 on an active is the same as everything on 10 on a passive.

As a result, try halving your passive values. If you passive bass is 4, try 2, etc.

 

[Sebastian]

Active tone circuits have positive and negative movement whereas passives only have negative. Having everything on 5 on an active is the same as everything on 10 on a passive.

Where did you get that from? I think that's incorrect.

Both types should be equal at "noon", i.e. '5' on passive and ±0 (dB) on active.
Regardless of the amp type, the active tonestack always has movement from -12 dB to +12 dB.
The passive tonestack works just like the physical counterpart of the amp type, causing different values from amp to amp.
So it doesn't work like "halving your passive values".

 

[Rex]

Without knowing the actual code behind the amp block, I think luke is at least approximately right. Passive tone controls can only cut; they can't boost. So a maxed-out passive tone knob would have zero cut. It would be the same as an active knob that's set to noon.

 

[Sebastian]

Without knowing the actual code behind the amp block, I think luke is at least approximately right. Passive tone controls can only cut; they can't boost. So a maxed-out passive tone knob would have zero cut. It would be the same as an active knob that's set to noon.

Then think about it like that: at "noon"...
... the passive tone controls are half open
... the active tone controls are neutral and set to give the sound like regular controls at "noon"/value of 5.

Not that difficult

 

[Rex]

Then think about it like that: at "noon"...
... the passive tone controls are half open
... the active tone controls are neutral and set to give the sound like regular controls at "noon"/value of 5.

Not that difficult

Not that difficult at all to think about it that way, but that's not how it works.

Passive tone controls can only cut. That's the key. The most gain that a passive tone control can produce is 0 dB,and that's when it's cranked wide open (at 10). And 0 dB is right in the middle of the range for an active tone control (at noon).

To put it another way, when a passive tone control is half open, it's actually cutting the signal. An active tone control has to be below halfway to cut the signal.

 

[Deaj]

Not that difficult at all to think about it that way, but that's not how it works.

Passive tone controls can only cut. That's the key. The most gain that a passive tone control can produce is 0 dB,and that's when it's cranked wide open (at 10). And 0 dB is right in the middle of the range for an active tone control (at noon).

To put it another way, when a passive tone control is half open, it's actually cutting the signal. An active tone control has to be below halfway to cut the signal.

This is correct

 

[Sebastian]

Not that difficult at all to think about it that way, but that's not how it works.

Passive tone controls can only cut. That's the key. The most gain that a passive tone control can produce is 0 dB,and that's when it's cranked wide open (at 10). And 0 dB is right in the middle of the range for an active tone control (at noon).

To put it another way, when a passive tone control is half open, it's actually cutting the signal. An active tone control has to be below halfway to cut the signal.

You are right by your terminology but that's not the way it is implemented in the Axe-Fx.
I understand what passive and active means, no need to explain.

I've been "aboard" since before the introduction of "classic passive tonestacks" on the Axe-Fx; before that, there was just the active version.
Unless something has drastically changed along the way and without me noticing, the way these dual tonestacks are implemented in the Axe-Fx is just as I described:
- default passive setting is at noon which equals "5" on the scale. This gives motion in both directions. Per definition, a value of "8" is actually not more gain but less cut.
- default active setting is at noon which equals "0 dB" and gives the same sound as the passive tonestack at noon. The absence of cut does not mean that the equivalent setting of the passive tonestack would be "10"! It's "5" - knob at noon.

Given these facts, the notion that "halving passive values" to get to the active values can't be universally true, as the active controls always have the same amount of boost/cut (+/- 12 dB) while the passive controls differ from amp to amp (otherwise they could not reflect the knobs' settings on the physical counterpart, which is claimed by FAS).

 

[Rex]

You got me thinking. I played around a bit with the active and passive stacks with a couple of amp sims. I have to admit: at noon, there's very little discernable difference between active and passive.

 

[Deaj]

You are right by your terminology but that's not the way it is implemented in the Axe-Fx.
I understand what passive and active means, no need to explain.

I've been "aboard" since before the introduction of "classic passive tonestacks" on the Axe-Fx; before that, there was just the active version.
Unless something has drastically changed along the way and without me noticing, the way these dual tonestacks are implemented in the Axe-Fx is just as I described:
- default passive setting is at noon which equals "5" on the scale. This gives motion in both directions. Per definition, a value of "8" is actually not more gain but less cut.
- default active setting is at noon which equals "0 dB" and gives the same sound as the passive tonestack at noon. The absence of cut does not mean that the equivalent setting of the passive tonestack would be "10"! It's "5" - knob at noon.

Given these facts, the notion that "halving passive values" to get to the active values can't be universally true, as the active controls always have the same amount of boost/cut (+/- 12 dB) while the passive controls differ from amp to amp (otherwise they could not reflect the knobs' settings on the physical counterpart, which is claimed by FAS).

Interesting stuff. I've never used the 'Active' tone stack in the AxeFX. I just assumed that the active's implementation was similar to, say, a Rivera amps tone stack. With the active predating passive tone stacks in the AxeFX the Actives implementation as described here makes good sense. I think I'll play around with the active tone stack a bit. Thanks for the further clarification.

 

[luke]

I see this has dissolved into a semantics argument.

If you normally have your passive bass set at "8", you are performing a 20% CUT.

"Noon" on an active is relatively the same as wide open "10" on passive system, to have a similar tone, you need to subtract 20% from "noon". Since we associate "noon" with "5" on the dial, 5 x.8 = 4.

Since 4 is HALF of 8, I stand by my initial statement.

Of course they do not translate EXACTLY, as we assume the virtual pots taper as the amp's would. However, halving the values will get you close.

The pots are really parametric EQs and I'd assume the resonant frequency and Q of the active option is different than the passive tonestack the amp normally has, which will yield variation from an absolute translation of halving.

 

[Tubed to Life]

In the POD manual, it says an standard passive control amp is: bass and treble boost from 0-10, mid reduces cut from 0-10. Hence a 'flat' eq is bass and treble at 0, mid at 10.

The pots are really parametric EQs and I'd assume the resonant frequency and Q of the active option is different than the passive tonestack the amp normally has, which will yield variation from an absolute translation of halving.

I assumed only the decibel level was affected in either case - a logarithmic response for passive, and something else for active (kind of like the difference between just and even tmeperaments).

Anyways, so I'm still wondering whether anyone has any patches they're using and wish to share. I haven't gotten to this, because I've been re-doing and consolidating my amps.

 

[Trazan]

Yes, passive eq can only attenuate, not boost. But saying that a passive eq at max will be the same as an active at 0 is wrong. A passive eq design will often be designed to have a fixed loss across all frequencies in their "flat" position. Thus, even though the overall level in such a design will be attenuated, each filter will act as a boost.

There's not much "flat" in a guitar amplifier design, and how the different filters are implemented in the Axe, I have no idea...

 

[Sebastian]

I see this has dissolved into a semantics argument.

This was not my intention, but the misunderstanding kept going on, so I had to explain in more depth.
Actually it's you and has been Rex who are stuck in the semantics; you're arguing by pure terminology/theory, disregarding what's actually going on in the Axe-Fx.

If you normally have your passive bass set at "8", you are performing a 20% CUT.

This can only be analytically true if the control works linear; from my understanding this is rarely the case.

"Noon" on an active is relatively the same as wide open "10" on passive system, to have a similar tone, you need to subtract 20% from "noon". Since we associate "noon" with "5" on the dial, 5 x.8 = 4.

No! On the Axe-Fx "noon on active" is not the same as "wide open 10" on passive. Noon is the same for both. The active tonestack at noon (= 0 dB) "inherits" the sound of the passive tonestack at noon.

Since 4 is HALF of 8, I stand by my initial statement.

It's based on wrong notions.

The pots are really parametric EQs and I'd assume the resonant frequency and Q of the active option is different than the passive tonestack the amp normally has, which will yield variation from an absolute translation of halving.

The active tonestack is totally different to the passive tonestack. There's no interaction between b/m/t and all of them have the same cut/boost, and their Q probably stays the same over the whole range.
The passive tonestack differs heavily from amp to amp, there're all kinds of interaction between b/m/t going on and so often they do more to the toneshaping than a simple "less" or "more" of what they're named after. Ever increased the treble and actually increasing the preamp drive by that?

I don't think this discussion is useless as it helps understanding what's going on in the Axe-Fx and which setting may be useful for what approach.
But after all only one "rule" is important: use your ears!
Doesn't really matter how to "calculate" passive settings to active; dial them in to sound well.

Seb

 

[Stratoblaster]

I've played with the active tone stacks since my Ultra days and had a couple of presets in the II FW6.x using them. The interaction of a conventional passive TMB can be, at times, frustrating and limiting for me. I've not played with the Active stacks in 7 presets yet, but will be since I like flexible EQ's, etc.

In a perfect world, you could set the individual Q and Frequencies for the Active tone stack; full parametric EQ in that part of the circuit would be very useful and it would be interesting to really play with the voicing/EQ in that stage of the circuit.

 

[symphx]

I didnt read all the above debates, however I used to use active but it seems to compress the sound all around, I used to think it was cool but now I just tweak the passives to taste.

 

[Tubed to Life]

I don't think this discussion is useless as it helps understanding what's going on in the Axe-Fx and which setting may be useful for what approach. But after all only one "rule" is important: use your ears!
Doesn't really matter how to "calculate" passive settings to active; dial them in to sound well.

Seb

Carry on, my firm-minded bro.

I didnt read all the above debates, however I used to use active but it seems to compress the sound all around, I used to think it was cool but now I just tweak the passives to taste.

[re-thinking/writing my last] Well, sure, that's what I've been doing. But having, most recently, come from using a Rocktron Taboo Artist, where it has a 4-band fully parametric eq, and liking some tones a bit (as much tone as the thing can give, anyways), I was curious what might come from a similar approach using the active tone stack. I've tried similar using a PEQ block, with both passive and active tone stacks, in the latter leaving the stack zeroed, and using the PEQ block for tone shaping.

So I'd been neglecting this, and jumped on the wagon for a spell to give it due. But I'm removing it because i'm not happy with at least the 'mixed' effort. I'll return with something simpler.

 

[Sebastian]

Carry on, my firm-minded bro.

I'm not sure I understand you...

But anyay, I was just pointing out matters of fact, leaving my mind out of the equation.