Riccardo,
Nice walnut top, the back will be the same. The 20th Anniversary model was released in '89, some basses were made and released in '90. I have the maple top/back version of this, number 041. It has a maple core, I believe the walnut basses have Alembic's standard mahogany core. If this is your bass then you have the elecronics figured out. If it's not your bass then the electronics are a such: each pick up has it's own master volume, low pass filter and Q switch ( add 6db boost to filter setting). The point knob is a pick up selector: neck, both, bridge, stand by. The little toggle next to the 1/4 jack is a mono/stereo output switch. Sorry if you knew that already.
The most similar Alembic model is the Mark King Signature. Replacement cost for a new bass is $9200. Thats based upon a MK Signature Standard with upgraded flame walnut top and back, purple heart neck laminates, omega cut out, Annniversary electronics and brass back plate. Price arrived at via the qoute generator. That's if you buy direct from Alembic.
Market price? Hmmm, 20th Anniv basses don't come up for sale very often. Maybe one of the regular ebay/price watchers would be able to provide realistic information. I'd pay about a third of the replacement cost for a used, in better-than-good condition 20th. But that's me and not to be taken a market indicator. The ability to reason can escape some people if the right instrument happens along.
Hope that helps. Beautiful bass.
Mike
