Audiophile Tube Output Transformers
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.
We have been producing tube output transformers continuously for over 75 years, constantly improving and tweaking their performance. The output transformer is one of the most critical components in a 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. Many "newbies" to the industry use frequency specification data at milliwatt ranges to inflate their claims. Check carefully when comparing manufacturers specs. We use -1db roll off points to ensure a typical HAMMOND 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 VAC RMS.
Our transformers are of EI laminated design, we do not offer toroidal designs due to their inability to handle tube imbalance and high manufacturing cost.
More importantly, our designs are "ear tested". After a new design has passed our extensive testing, it's got to sound good too, before we put it on the market! From Bach to rock & three watts to 280 watts, we have your output transformer IN STOCK.
Single Ended Tube Output Transformers
These high quality units are designed for maximum versatility. Designed for both triode or pentode operation - Class A operation. All units include an optional use - 40% screen tap (a proven pentode "sweet spot") for "Ultra-Linear" operation. The ratings shown are at full power and rated plate current. Available in 25-75 watt models (our 1627-1642 series) 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 ratings. All single-ended output models include multiple interleaved windings to maximize high frequency response. These windings are machine wound with high quality copper wire. If you do not need hi-fi ratings or are restoring older equipment using single ended audio output - refer to our economical 125SE series optimized for single ended - universal - general purpose use. Available in 3-25 watt models.
Push Pull Tube Output Transformers
These high quality units are also designed for maximum versatility. All units include an optional use - 40% screen tap (a proven pentode "sweet spot") for "Ultra-Linear" operation. They are designed to be used with most all power output tubes available today. The ratings shown are at full power and rated plate current. We have also added an epoxy potted series to our line for the ultimate in tube output transformers. Available in 10-280 watt models (our 1608-1650 series). If you do not need hi-fi ratings or are restoring older equipment using push-pull audio output - refer to our economical 125 series optimized for push-pull - universal - general purpose use. Available in 3-15 watt models.
HAMMOND Interleaved Windings
The reason for our sparkling high frequency performance is the use of interleaved windings between the primary and secondary. The number of interleaved windings is optimized to the size (wattage) of the unit. All high fidelity output models (both single ended and push-pull) include multiple interleaved windings to maximize high frequency response. These windings are machine wound with high quality copper wire The multiple interleaved secondaries are wound (series or parallel connecting them) to match to 4, 8 or 16 ohm load impedances. The primaries of each model (including the "single-ended" series) include Ultra-Linear taps at the 40% point.
Tube Output Transformers - Aesthetics
We have also paid close attention to the "look" of our units as they are as much on display in some designs as the tubes themselves. Our high fidelity units 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.
