Hammond 1750Z 20W Paper-Wound Output Transformer, 10K C.T. Primary

The 1750Z is a 20 watt push-pull output transformer for tube guitar amplifiers, designed for drop in replacement of original units such as the Traynor Bass Mate YBA-2 (A1313). It is intended for technicians and owners maintaining Yorkville/Traynor amplifiers, and it also appears in the Gibson section of the series ordering table with the same ratings.

This paper wound transformer couples a 10,000 ohm center-tapped primary to an 8 ohm secondary. Typical frequency response is 70Hz to 15KHz (0/-1dB referenced at 1KHz), with distortion below 1% at 70Hz. Primary DC resistance measures 608.7 ohms (brown-red) and 651.5 ohms (red-blue); the black-green secondary measures 0.706 ohm. Primary inductance is 164H (64.0 K ohm) at 60Hz, 10.0 V, and primary leakage inductance is 141.8mH under the same test frequency.

Design specifications and materials were kept as close as possible to the original part to preserve the stock tone, and the unit is constructed to look similar to the original where possible. It is an open style transformer with primary and secondary leads at least 15 in long. Dielectric strength is 2000VRMS and the rated temperature range is -40 to 105 degC.

Drawing dimensions are A 3.688 in, B 2.400 in, C 2.308 in and D 3.125 in, with a 0.187 in mounting slot (G). Shipping weight is 1.7 lbs (0.77 kg). The 1750Z is RoHS and REACH compliant; amplifier model names are trademarks of their owners and are listed for reference only.