Hammond 1750WA 100W Twin Reverb Output Transformer, 2/4/8 Ohm

The 1750WA is a 100 watt push-pull output transformer for tube guitar amplifiers, designed as a drop-in replacement for the original unit in the Fender Bassman 100, Quad Reverb 100, Showman, Super Six Reverb 100, Twin Reverb and Twin Reverb 65 Reissue. It is listed as similar to Fender part numbers 125A29A, 022689, 022889, 022899 and 037612, and adds multiple secondary taps for flexible speaker matching.

A 2,000 ohm centre-tapped primary (blue and brown with a red centre tap) drives 2 ohm (yellow), 4 ohm (white) and 8 ohm (green) secondaries from a black common. Typical DC resistance is 19.38 ohm brown-red and 20.23 ohm red-blue on the primary, and 0.048, 0.073 and 0.132 ohm on the black-yellow, black-white and black-green secondaries.

At 1.0 kHz, 1.0 V open circuit, the brown-blue primary measures 4.38 H (26.7 KOhm); secondary readings are 6.52 mH (101.6 ohm), 12.83 mH (192.9 ohm) and 26.41 mH (353.6 ohm). Primary leakage inductance is 88.36 mH. Frequency response is 70 Hz to 15 kHz (0/-1 dB reference @ 1 kHz), with distortion under 1% at 70 Hz.

The bobbin-wound, open-style unit has 12 in minimum leads. Drawing dimensions are A 4.063 in, B 3.450 in, C 3.500 in, D 3.500 in, E 2.250 in and F 2.800 in, with G 0.187 x 0.300 in. Ratings are 2000 VRMS and -40 to 105 degC. It is RoHS and REACH compliant and ships at 4 lbs (1.81 kg).