The Cerwin-Vega CVA series looks promising. A 2X8, one of which is coaxial, and a 400 watt continuous power amp. 99dB @ 1w/1m, 70 Hz to 20 kHz, 60 Hz @ -10dB, 48 lbs . Could be good for vocals, acoustic or electric guitar, violin, or mandolin. Add a CVA subwoofer for bass and keys. Looks like they recommend 2 or 3 of the 2X8's to match with the 21" sub, but I'd probably stick with the 15".