K2 : BioSonic

Review:
If you managed to find one of these packs, consider yourself lucky. K2 released the Biosonic for the '03 season, and then discontinued it for '04 while they work on redesigning the speakers. That's right, speakers. K2 built a set of small, flat speakers into the shoulder straps, added a battery pack to power them, and put power and volume buttons on one of the straps. The result isn't best pack storage capacity or the best sound quality, but man is it ever a cool concept!

It is a smaller pack, so while it will easily hold a couple of extra layers and a few snacks, don't expect to take it on a major hike. The speakers get pretty loud before distorting, so you can provide the tunes for yourself and your friends on the hill. The pouch for the music player isn't very convenient, some kind of upper pocket like K2's Axon has would work, or even better a front pouch on the shoulder strap could easily be big enough to fit a music player without getting in the way.