Hammond 1642SE 75W Single-Ended Triode Output Transformer, 5000 Ohm

The 1642SE is the high-power model of its series: a 75 watt single ended output transformer with a 5000 ohm primary and a 300 mA DC bias rating. It is designed principally for high impedance triodes, with parallel 211, 572, 811A or 845 suggested, making it a candidate for builders of large, high-output single ended triode amplifiers.

The 1627-1642 Series is "over designed" for high fidelity, single ended, Class-A tube output circuits. Each transformer is enclosed (shielded) and uses high quality (M6) grain oriented silicon steel laminations, with a gapped core to reduce core saturation in Class-A amplifier circuits. Insulated flexible leads are 8" minimum, and the case uses four slot, chassis Type "X" mounting with 0.20 x 0.38 in (5 x 10 mm) slots.

The 1642SE does not include the 40% screen tap found on most of the series. The secondary offers 4, 8 and 16 ohm connections, listed primary inductance is 53 Henrys, and the hipot test rating is 3500 VRMS, higher than the 2000 VRMS of the 30 W models. Frequency response for the series is at least 20 Hz to 20 kHz at full rated power (+/- 1 dB max., ref. 1 kHz). RED connects to B+ and BLUE to the tube plate.

This is a substantially larger unit: overall dimensions are A 4.38 in (111 mm), B 7.50 in (191 mm), C 5.25 in (133 mm), D 3.50 in (89 mm) and E 5.88 in (149 mm), and it weighs 28 lbs (12.70 kg). Mounting slots are 0.20 x 0.38 in (5 x 10 mm). RoHS and REACH compliant, UPC 623980208206.