Monoprice Rechargeable Mini Headphone Amplifier for Guitar - Tube Overdrive

Sounds great, if you don't mind fiddling with the gain and volume, and being extremely careful about putting on headphones until you have the volume correct. If your jacks aren't very securely plugged in, you may only hear the right track.I found that if I follow this order, it works and I don't blow my eardrums:hook external source into the aux input jack *securely"connect headphones *securely*turn the amp onplug the amp into your instrumentadjust volume and gain until you can hear your external sourceadjust instrument volume until you can hear itput on your headphones.

Sucks. Horrible sound