I've reworked the amp circuit on this one. There is a buffer in the front end and a speaker out option (which would also be a serious Fuzz plugged into the input of a guitar amp) I put a treble boost and a gain control on this one as well. If you're using the internal amp and speakers you can plug another instrument in to the out put jack and then that instrument will go through the built in system too.
I haven't worked out pricing yet but he'll be looking for a home soon.