Hammond 1750KA 50W Bassman 59 Reissue Output Transformer, 2 Ohm

The 1750KA is a 50 watt push-pull output transformer for tube guitar amplifiers, designed as a drop-in replacement for the original unit in the Fender Bassman 59 Reissue, Concert and Vibro King. It is listed as similar to Fender part numbers 36485, 125A9A and 022855, with reference chassis numbers 6G12, 6G12A, AA763, Blackface and Brownface.

Its 4,150 ohm centre-tapped primary drives a 2 ohm secondary. Typical DC resistance is 45.53 ohms brown-red and 49.09 ohms red-blue on the primary and 0.140 ohm black-green on the secondary. At 1.0 kHz, 1.0 V open circuit, the primary measures 11.3 H (71 KOhm) and the secondary 4.20 mH (162.10 ohm); primary leakage inductance is 5.16 mH.

Frequency response is 70 Hz to 15 kHz (0/-1.0 dB reference @ 1 kHz) with distortion under 1% at 70 Hz. The paper winding and materials were kept as close as possible to the original part to preserve the stock tone. It is rated 2000 VRMS dielectric strength and -40 to 105 degC.

The open-style transformer has generous 12.0 in minimum leads: blue and brown primary with red centre tap, black common and green 2 ohm. Drawing dimensions are A 4.050 in, B 3.280 in, C 3.500 in, D 3.500 in, E 2.050 in and F 2.570 in, with G 0.187 x 0.300 in. It is RoHS and REACH compliant and ships at 5 lbs (2.27 kg).