This Deluxe Reverb was built in 1970, which means it still retains the AB763 circuit, as indicated by the tube chart inside the cabinet. Because of this it's a great value buy, when compared to AB763 amps from the Blackface era - and many would argue the sound is very close. The sound on this amp in particular is excellent, regardless of comparisons it is a very good representation of the classic mid-sized Fender amp. Internally, it's has a changed power cord and electrolytic caps, but is original otherwise, retaining all of it's stock resistors and coupling caps.