Originally Posted by Barongket
My son's music teacher gave it to him. He didn't know much about it and it has no instructions. It has four dime sized copper discs that attach to the bridge. My question is do we attach to the top or bottom and what type of adhesive do we use. Do we tape it or glue it? I thought someone might be able to help. I didn't know they had different types.
That's called the Double Big Twin. It's good for pizzicato, not as preferable for bowing because it's close to the strings and gets a lot of the "scratchiness" in the sound. A preamp is strongly recommended, as it has less gain (it's "stuck on" rather than under pressure) and the impedance buffering for this particular pickup is very helpful.
The pickup originally came with adhesive (like a very strong double-stick tape) and each pickup is adhered under each string, about 1/4" away or so from the top of the bridge. You can experiment with some putty (Poster-tack, plumber's Mortite, etc. all work) to see how you like it, and then use superglue to put them on. I can also send you some of the adhesive for a nominal cost.
PM me with an email address, and I'll send you some helpful instructions.