Bass tube preamp voicing's like Digitech BP8?

[davesisk]

Hi folks:

I have a used Digitech BP8, which is a bass guitar tube preamp + digital effects processor in a footboard configuration.  I love the tube preamp in this thing.  IMHO, it's up there in terms of sound with some of the high-end rack-mount bass tube preamps.  It has 9 selectable "voicings" (list posted below).  There are some things that I don't like about it (like the millisecond drop out when you switch patches, etc.)  I have toyed with the idea of building a bass tube preamp + analog effects in pedal form, since no one currently makes anything like this nowadays.   I'm thinking tube preamp w/several voicings + good analog compressor + flexible analog semi-parametric EQ + good analog chorus + good analog delay...something along those lines.

I generally use the Warm/bright voicing, as that adds some middle lows to my tone (the warmth) and some highs (the bright).   This is without doing anything with the onboard 4-band semi-parametric EQ...tube preamp section only. I also use the tube saturation voicing for a distorted bass tone, and am experimenting with some of the other voicings.

So, here's my first question:  What do they do to get the different voicings out of the tube circuitry?   Is it a matter of how much current or voltage you send where to the tube and/or transformer, or is there additional circuitry (like some sort of EQ circuit) involved?

Here's the list of the available voicings:
CLn1=Warm Tube,
CLn2=Warm Bright Tube,
CLn3=Punchy,
CLn4=Punchy Bright,
CLn5=Classic Tube,
CLn6=Classic Bright,
CLn7=Backbeat,
CLn8=High Definition,
CLn9=Full Five String,
CLn0=Modern Five String.
HSuS=Dark Distortion,
SAt=Saturated Tube Distortion,
Od=Overdrive Distortion

Any thoughts on this appreciated.

Also, I know what I want, but I know I don't have the skill to design and build this.  I do however have the skills to market and sell it with reasonable success.  If anyone would be interested in working with me on design/build of this as a business partner, please shoot me an email at davesisk@ipass.net.

Thx,
Dave