Volume pedal retrofits = more consistency?

[sfr]

I have a passive Ernie Ball Jr. volume pedal.   Lately, I've started using it towards the middle/end of my chain, after a whole big mess of pedals; the only things after it were the trem and delay, now the flanger is there as well, simply because it's in the same box as the the latter two pedals.

Anyway, from a playing perspective, this position allows me greater versatility with the volume pedal.   The only problem is that the reacts wildly differently depending on what pedals are on before it, particularly distortions/boosts.  It's almost like throwing an entirely different taper pot in the damn thing every time I turn on pedals. 

I'm aware of some of the benefits of using something like the Anderton volume pedal retrofit - but I'm curious, will a solution like this help alleviate some of the inconsistencies I'm seeing?   Will I run into headroom issues, as I'm often running a very "hot" signal at this point in the chain?

[Mark Hammer]

The stock VPR actually allows for some custom-tapering of the control pot, since it merely serves as a source of current to feed to pin 5.  You could easily adjust the range of the pot with assorted series and parallel resistors if you wanted.

Missing from the basic schem, though (http://www.tonepad.com/getFile.asp?id=2) is any way of adjusting the input sensitivity, or compensating the output level for that particular input sensitivity.  You may be aware that 3080 OTAs are not known for their ability to comfortably handle hot input signals.  The input impedance also doesn't strike me as something to write home about.

In some respects, if one wanted a version of the circuit that could allow it to be inserted anywhere in the chain for any purpose, you'd probably want to add some sort of FET buffer ahead of the 3080, and add variable gain to the Bi-Fet op-amp.

You know, it's probably time for a redesigned stereo version of this, using a 13700/13600, with a proper input buffer.

[sfr]

You may be aware that 3080 OTAs are not known for their ability to comfortably handle hot input signals. 

That's what I was kind of thinking when I asked if I'd have "headroom" issues...

The thing is - *ideally*, I want a solution that sort of always works the same, regardless of what's on in my chain, whether I'm running the guitar signal straight, or I've got 6 pedals on before the thing.  Without switching a toggle, or changing modes on the volume pedal or having two volume pedals or anything.  (I suppose if I ever got that electronic switching implemented, it would be easy to have something change in the volume pedal circuitry when certain other pedals in the chain where on...) 

When the pedal is all the way up, I want the signal to be the same level as if the volume pedal wasn't there, (this is important, sometimes I'm running those very hot signals at that point for a reason) when the pedals full down, I want there to be no signal, and there should be a gradual taper between those two volume levels as things change.   

Of course, the problems I'm observing now are probably also coming from how our brains hear sound - running these hot signals, I can hear things like my trem reacting differently to the attenuated signal from from the volume pedal sooner in the sweep than I would hear a change out of the amp with my ears if the trem was off.  I'm sure the natural compression and overdriving of the tube amp at the end of the chain has something to do with this as well...   And this is something I use to effect - changing the "depth" of a trem by attenuating a hot signal, cleaning up the amp without drastic volume loss by attentuating the signal - So probably, I what I think I want and what I actually want are actually two things.  (Which is often the case) Or perhaps I actually want two different things. 

Of course, I want the single volume pedal in my chain to understand those two things and when I want either of them.  (Does anyone have a schemo/layout for a mind-reading device? )  And of course, getting my volume pedal to behave entirely differently is probably like switching between two drasticlly different guitars - the feel is different and it's a bit harder to do things blind.  (And being a singer and guitar player with way too many pedals, I end up doing a lot of stuff blindly.)

I guess I'm just thinking out loud again.