I'd be curious to know the purpose of each of these 14 knobs!
I'd say he's just another Phil Lesh wannabe.
Seriously, though, from here:
http://deadsources.blogspot.com/2013/12/spring-1971-phil-lesh-interview.html :
Harrison: So the new bass is quadriphonic, which will allow an array of effects across the stage out to the audience. And you can stagger these effects as you see fit?
Phil: Yes. I have a six-position switch which Ron Wickersham has designed. This switch has the percussive distributions that I want.
and:
Harrison: This new bass also has a second stage which is still under development, is that right?
(and)
Phil: Actually, one is the bass and the other is the little black box with the pedal controls, which has some extra toys in it. The bass also has regular pickups with modern, efficient tone controls that actually boost certain frequencies and in certain band widths. Then it has the quadriphonic or the individual string pickup option. This, then, approaches a bass synthesizer concept. The foot-pedal black box would have four channels. It would essentially be the same thing as all of my four Fender pre-amps. It would have four inputs, and it would distribute itself to the four inputs in which I would have volume, treble and bass controls and a bright switch for each channel –
Harrison: What is stage three?
Phil: This is the one that has to have the relays built into the neck.
Harrison: Oh…the computer!
(leading to):
Phil: Exactly. The only control on that bass, hopefully, would be a master volume and a function switch which will indicate pickups, quadriphonic, or computer, or whatever. Of course, the individual pickups would have volume controls on them for balance, but there would be very few tone controls.
So after all that I still don't know what each knob is for. :glee:
Edit:
In comments on the interview one of the posters says this:
"Phil goes into great detail about his new bass, and the future designs that Ron Wickersham is working on for him. Blair Jackson gives some more info on this bass in Grateful Dead Gear, p.108 - it was introduced by Alembic in winter 1971, shortly before the interview.
"The entire bottom half of the guitar [was] devoted to an easily accessible electronics compartment and 14 knobs... [As of early '71 there were just 12 knobs.] There were three Alembic pickups: two low-impedance trapezoid pickups with external hum-canceling coils, and one that was quad (an output for each string). The extensive network of electronic modules allowed for control of bandwidth, frequency response, resonance, and various filtering (highpass, lowpass, bandpass, and notch...). 'My goal...was a kind of infinitely flexible tone control,' Phil comments today, 'but it took too many knobs to do it.'"
Harrison is curious about the quadraphonic possibilities of the new bass, but it's hard to say how much Phil actually used that aspect of it, since we don't hear the effect of each string coming from a different speaker, except on a few tapes from late '72/early '73.
And there you have it.