EDIT time...  
 
An integrated tone/volume (on 1 knob system) provides more real estate, and removes the need for two drilled holes.  

I think it is the case that Alembic doesn't do stacked pots.  I think it was an issue related to the quality of the pots.

I don't see why not... They are not sharing any circuits. This will be a check point...

I don't know much about pots.  I do know that Alembic uses sealed self-cleaning mil-spec pots, and that Alembic does not compromise on quality.  I think there are some earlier threads on the subject that may have more detail.

Hal,  
See Haddimudd's double neck bass
 
I believe it was quite a task and was unlikely to be repeated.
Mike

Maybe there are better quality ones now...

I remember we were discussing a volume/tonal locking system... Although it seemed a little far fetch, but from the perspective of minimizing knobs, an integrated tone/volume (on 1 knob system) would make the bass more sublime and give a minimal look and feel.  
 
 

I like it...Congrats....

I wanted stacked pots back when I was having mine done in 2004 and the answer was absolutely not.  
 
I have to say I'm no fan of this body shape from a practical perspective.  You seem to be forfeiting some real estate for the electronics cavity and moving the controls closer to the strings where they might be in the way for some playing styles.  If it suits you, though, then more power to you!
 
You also seemed to mock up the bass with a partial BTC.  Was that intentional, or just how you slapped things together?

Bob's right, no on the stacked pots - for a Series I or II, the bass would have to be much thicker to gang three sections of those huge pots. Take the backplate off your Series I. See how the filter pots are two sections each? Now add a third one and you'll see what I mean about how much more insanely thick the bass would have to grow.
 
Then you have the ugly knob issue. Stacked pots need long knobs that are easier to break, or wide ones that cover up too much wood.

Thanks Craig.
 
Bob, different strokes for different folks.  
 
After owning both types of Alembic Series Basses: The Omega Body (1979), and the Small Body (1976)
there were always people liking one style over the other... and you know what? That's cool because I still owned and loved both of them. You want to to know something else... I never seen an Alembic I didn't like.
 
Also, if the bass has to have 4 knobs, so be it... (It will still look great to me anyway).  
 
However until Mica tell me any different, 2 knobs will be the rule on this bass.
 
Frankly speaking, this bass was created to break rules -  
 
I done my time, with others designs...

Hi Mica,
 
I am glade you commented on the knobs... As you can see from the concept, I added the 4 knobs back. The knobs are over 1 1/4 from the edge;
and switches are end to end very well positioned for my taste.
 
The top crown, should match the uniformity of the body. I am working on a detailed design on the finger board.
 
Thanks  
 

By the way, there' a Dreaming for now board for threads like this.  Maybe this can be relocated to where it belongs?

I don't know what you're planning for neck woods, but you may be looking at a bass with poor natural balance.  If the body is smaller and lighter than an SC, then you're going to need a lighter neck to get balance.  Unfortunately, a thin neck made of lighter woods isn't going to be super stable.  You might want to use some dense wood in the neck to get better stability and tone in a smaller dimension.  Those woods, by definition, are heavy and may result in a bass with some neck dive.  You might want to consider lengthening the upper horn, or both horns if you want symmetry, so that your strap attachment point is closer to the headstock.

I am already aware of these things you mentioned...  
 
This bass will be balance, and it will be of quality in every way.
 
The design is special and I will not go any bigger or smaller...  
 
If I have to lighten up on the crown, so be it, no problem.  
 
If the neck have to be lighter, no problem.
 
A thinner neck was already discussed with Mica, so life is still be good.  
 
To be completely honest, being in a position to build you own instrument (especially if it's an Alembic) is great problem to have my anyway.
 
I am a blessed person with or without the bass Bill. I am not defined, I define. Human have this great parameters if they believe...  
 
So, I am not going to run away from one of my most cherished dreams in making myself the best bass in the world. It will get done, and done correctly.
 
Lastly, no strap pins would ever touch my horns.  
Nuff-Said there...
 
Thanks for your honesty, it is most appreciated.