Audio/Output Transformer Prices                              Single-Ended Ultra-Linear Hi-Fi Specs.              

    Push-Pull / Ultra-Linear Specs.                                  Single Ended Universal 3-25 W Specs

    Push-Pull Universal 3-15 W Specs                             Inter-stage Transformers

    RCA Radiola III Audio Transformer                             Power Transformers & Chokes

Whether you are into the clean, free-spirited "Single-Ended" tube output or high efficiency, high power, "Push-Pull" audio, we have the output transformer for you.

Hammond have been producing tube output transformers continuously for over half a century, constantly improving and tweaking their performance. The output transformer is one of the most critical components in an audiophile amplifier. These excellent designs have survived the years and have enjoyed a recent resurgence along with the tube industry.

Please note, our specifications are at FULL OUTPUT power. Hammond use -1db roll-off points to ensure a typical conservative rating, again at FULL OUTPUT POWER.

To ensure a long life and maximum versatility these units are built to and tested at a Hi-Pot rating of 2,000 volts AC!!! Hammond transformers are of an EI laminated design. Toroidal designs are not offered due to their inability to handle tube imbalance and their high manufacturing cost. More importantly, these transformers are "ear tested". After a new design has passed extensive testing, it has to sound good before it is put on the market. From Bach to Rock 'n' Roll and 3 watts to 280 watts, there is a Hammond Classic Transformer right for you. 

These high quality units are designed for maximum versatility and for both triode or pentode operation – Class A operation. 

All units include an optional use 40% screen tap (a proven “sweet spot”) for Ultra-Linear operation. The ratings shown are at full power and rated plate current. The lamination iron used is a high quality (M6) grade silicon steel for low loss and the lowest possible distortion at bass frequencies. A factory set core gap ensures against core saturation at full rating. All single-ended output models include multiple interleaved windings to maximize high frequency response. These windings are machine wound with high quality copper wire.

        SE specifications                 SE transformer prices 

These high quality units are also designed for maximum versatility. All units include an optional use 40% screen tap for ultra-linear operation. They are designed to be used with almost all power output tubes available today. 

The ratings shown are at full power and rated plate current. Epoxy potted series are also available for the ultimate in tube output 

transformers.

       P-P / U-L Specifications                  P-P / U-L transformer prices

HAMMOND Interleaved Windings

The reason for the sparkling high frequency response in Hammond transformers is the use of interleaved windings between primary and secondary. The number of interleaved windings is optimised to the size (wattage) of the unit. All output transformers (both single-ended and push-pull) include multiple interleaved windings to maximise high frequency response. These windings are wound with high quality copper wire. The multiple interleaved secondaries are wound (by series or parallel 

connecting them) to match to 4, 8 or 16 ohm load impedances.

The primaries of each transformer (including the “single-Ended” series) include Ultra-Linear taps at the 40% point.

Tube Output Transformers – Aesthetics 

Hammond has also paid close attention to the “look” of their transformers, as they are as much on display in some designs as the tubes themselves. They are manufactured with high-grade laminations (M6) and machine wound with high quality copper wire. The core is varnished and oven baked to ensure quiet operation – even at high ambient temperatures. Then the end bells are bolted on. These end bells are finished in a tough, low gloss, black powder paint finish to resist scratching. The end bells include knockouts for optional above-chassis wiring.  

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