Looks to be a bargain gainclone and those using them want to
modify the power supply and get it off batteries.

I see the slot for this as a dedicated computer amp, but the
users are using it with their high end components like turntables
and getting a good response. Also some entrepreneurs are doing
upgrade tweaks.

• http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=300-952