This is one cool little amp! This Single Ended tube mic pre & amp came out of a mid 50s RCA Tape recorder. In the 50s, when Tape Recorders were all the newest hi tech rage, the manufacturers HAD to make the audio better than the existing phonos in order to sell this expensive new toy. This little amp has an aluminum chassis, well designed class A amplification using a hot 5879 front end tube, into two stages thru a 12AX7 then into a 6AQ5 pentode output. The 6AQ5 tube is the subminiature version of the legendary 6V6,considered the cleanest pentode made. .This amp will do Hi Z mics, instruments in line in, and give sweet tube-essence, clean or dirty depending on input level. The amp has been 100% re-capped with vintage American caps, electros replaced with higher values. The tubes are all vint.US NOS. The amp runs cool and very quiet. Note the size of the Power and output transformers. Way oversize for a single tube audio output. The power transformer is separate to the chassis. This was done to insure minimum hum, away from the hum sensitive tape head. Transformer could safely (hum & noise) be mounted to rear of chassis. Please note...Tube gear uses hazardous voltages and should only be operated by persons familiar with this type of equipment. We pix other available goodies at our sites. At this one, youre bidding only on described item. Added 6/24/23: The mic input is high impedance. Any mic transformer Lo Z to Hi Z can be plugged into the Hi Z 1/4 TS (guitar type jack).Also the Speaker output is transformer coupled Lo Z and can be plugged into a line input. Ive put a line termination resistor across output to prevent transient overload.