hi, i´m thinking to build an ashbory like bass with rubber strings, but i´m doubing in what kind of pickup use (no dealer for original parts). i´m spanish and at my local music store they have a small stock, my options are:
-under saddle transducer for guitar
-twin disc transducer for double bass
-multipurposal single disc transducer
i don´t wanna spend much money in it so all this pickups are under 50$ and i´m going to use a homemade piezo buffer.
by the way, wood or metal bridge?

I would use the 2-disc bass pickup with a wooden bridge.

Check out Trout Cove's piezo sample pack, it's enough to get started for only $30US.

http://www.members.tripod.com/~tclutherie/page6.html

You can get Ashbory parts here:

http://www.largesound.com/cart/agora.cgi?cart_id=1417134.16168*tX7P74&product=Parts

They only show the parts they have in stock, but they can get everything you need.

Jeff

The twin disc piezos have much better output compared to an undersaddle unit. I use the K&K Sound pure bass and get a great woody sound, but I haven't gone with the solid body design yet. I do an ebony bridge & saddle with the 2 piezo discs mounted directly under the saddle- one disc for each string pair. Here's mine:

http://www.roadtoadmusic.com/files/010BB_w_octave_black.JPG

+1 for the twin piezos. I used the K&K bassmax, the most powerful DB piezo pickup I know. In 3 years (until lost :( ) I never managed to add the preamp in the chain, the sound was plenty strong without preamp.