There's many thousands of dollars between the retail price of a Series I and Series II, but most of that is in woodwork, LEDs, etc. The electronics differences that you would pick up in a retrofit are pretty minor if you are electronically inclined at all.
The Q-switches select between three resistor values to pick the EQ curves. On the CVQ, the switch and resistors are simply replaced by a pot that sweeps through those preset resistor values. The retrofit would require the right pot value (sorry, I was near a Series I but not a Series II, can look it up if you like later) and two solder connections each. You would probably want to order CVQ pots from Alembic, as there's not enough space were the switch is to take a full sized pot. You may have to enlarge the hole in the faceplate too.
Master volume is relatively easy too. You need to find the output wires from the pickup volume knobs before they run off to the output jacks then splice in a dual ganged volume pot to act as the master volume. On a Series bass, the two pickup outputs are kept completely independent through the output jacks, so you use a dual pot for master volume instead of a regular one. Again, you can get the part from Alembic. The output jack area is VERY complex on a Series bass, and you can make a tech turn completely white faced when you pull the back plate off. But if you do this by thinking about intercepting the individual outputs before you get to that part of the wiring harness, all is easy. You'll need the dual volume pot, a knob, and you'll have to drill a hole in the faceplate. You could get even trickier and put the pickup volumes on a stack pot then put the master in the hole you just vacated too.
Even if you bought the parts from Alembic, I doubt that there would be more than $50 here. It's all labor, but there's not even much of that if you look carefully at how this works.
I think the master volume is a worthwhile mod for any Series bass, if you are willing to have another knob. CVQ really is a personal taste thing.
David Fung
