Harmon Kardon XT4 xt 4 input transformer sut step up mic in tube

Grommes Precision Mic Input Transformer Step Up sut

Altec 1588 Transistor Transformer Microphone Preamp Octal. Tested

Altec 1579A Transistor Preamplifier MAG PHONO RIAA W/ Transformer ISO output

DON McGOHAN MC-2 MICROPHONE PHONO STEP UP TRANSFORMER (AS ALTEC 4722)

UTC O-5 Ouncer Transformer Vintage Rare

Bogen T200 Step Up Transformer Pair on mount sut Mic in

Moving Coil Transformer SUT Box For Altec/Peerless 4722