Stepping into the amplified arena of music performance can be as easy as installing a pickup on your current instrument. A piezo transducer responds to pressure on the instrument's bridge (either in the wing slot, under the bridge feet, or from within the bridge itself). This makes piezo pickups the optimal choice -- if you're looking for great sound -- for bowed string instruments.
The standard pickup offered by Fishman attach to the wing slot of the instrument's bridge and usually require no alteration to the instrument. The Fishman V100 has decent output gain and is popular with more professional players.
For the more active performer who is willing to invest in a more ambitious setup which will involve alteration of the instrument, the L.R. Baggs bridge pickup offers a design that has the piezo carved inside an Aubert #7 Mirecourt bridge. (Diana Ladio of The Moxie Strings uses an L.R. Baggs pickup.) This provides more balance, greater output, and less attack noise, but the bridge requires installation by a qualified technician.
Another professional pickup is the Realist pickup designed by David Gage in collaboration with NS Design. The Realist is a transducer in a vinyl sleeve and rests between the bridge feet and the violin top, which puts it exactly where the sound is transferred from the strings to the sound board. Its mounting hardware is extremely compact and with such a high output gain it requires no external preamp. Though installation is relatively easy and can be done by the customer, the transducer raises the bridge height by about 1 mm and some players may want to have their bridge height lowered by a qualified technician.