This particular amp appears somewhat different to the usual AC55. It has seven valves, and.......one of them is sticking out of the back of the cabinet !! In fact, the "seventh valve" is actually stuck into the voltage regulator which was made up of a valve base by Elpico on this particular version. A previous owner has inserted a valve instead of the usual bridging plug, All the valve is doing in fact is acting as a bridge to close the circuit and hence power up the amp! This amp does have 6 working valves - as usual with AC55s!
Also, the cabinet back has three ventilation holes instead of the usual five.
As usual though, inputs are provided for Mike 1, Mike 2 and
Gramophone with separate volume controls and
shared bass & treble.