Yes i hear you shout, Ampeg make Bass amplifiers.  Yes but they also make guitar amps too! we know because we've seen broken Ampeg guitar amplifiers in for repair! 

Built to the high quality of all Ampeg bass amplifiers, their guitar amplifiers are solid and well constructed.  Repairs are rare however like everything general wear and tear faults develop.  

Fixing crackly pots 

Replacing capacitors causing hum

repairing intermittent problems with amp breaking down

Re valving and biasing 

Foot pedal repairs