Hello all.  I have been viewing several Youtube videos regarding the use of low cost acoustic exciters (Dayton appears to be the brand name, and they can be purchased on Amazon for under $10 each in low wattages).  They seem to be best mounted on 2 inch thick rigid styrofoam (tm) placed to avoid the creation of resident frequencies.  It is possible to produce a set of nice sounding speakers for about $30.  

An interesting property of the speaker system is that, because they lack the cones of a conventional speaker, the sound is equally dispursed throughout the room (much the same as when you wear head phones).  Frequencies below 150 hertz are not effectively produced by the exciters, so a sub woofer is often recommended.

I think that it would be possible to mount a low wattage acoustic exciter on a violin or cello (positioned on a "dual bridge" arrangement instead of the standard adhesive pad and held in place with the strings).  This would cause the violin to act as a speaker and may help to "play in" a new or restored instrument.

The exciters I have viewed appear to be 4 ohm, and a standard receiver operates on 8 ohms.  Two exciters could be wired in series to achieve 8 ohms.