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Shortest Way 51+ Amplifier

Shortest Way 51+ Amplifier

Regular price $627.00 USD
Regular price Sale price $627.00 USD
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Shortest Way 51+ Amplifier

This is a Class A, Single-Ended Triode (SET), output transformer coupled amplifier with no capacitors in the minimal signal path. Special attention was paid to minimize the number of components used in the signal path. All transformers are specially produced by a custom shop for the SW51 amplifier and are wound around specially selected steel alloys. The circuit has no additional feedback.

In classic SBAF and Zampotech tradition, this amplifier is also available with a bronze cat on the front.

Includes 1 matched pair of 6Ж51P vacuum tubes (6Z51P or 6J51P in English) tubes. Does not include a standard IEC power cable - An inexpensive power cable is sold separately as most users already have a box full of these stored away somewhere.

Nominal Specifications:

- Frequency range: 10Hz - 30kHz (+/- 1dB)
- Noise: -90dB
- Gain: 12dB
- Dynamic range at load from 24 - 600 ohm: 87dB
- Tubes: 2x 6Ж51P (6Z51P or 6J51P when translated into English). Also compatible with
EF184 tubes.
- Inputs: 10k ohm via RCA inputs
- Outputs: 27ohm low Z ¼” (6.3mm) output, 54ohm high Z ¼” (6.3mm) output
- Maximum Power Output: ~220mW at 32ohm (<0.7% THD)
- Maximum Power Consumption: 15W
- Power Cable: All North American units are configured for a nominal 115V mains voltage. Amplifier connector is via IEC C13 cable (common for many electronics in North America). 1A (minimum) current capacity (most IEC cables typically have 10A).
- Product dimensions: 7.8” L x 7.5” W x 5.1” H (195mm x 190mm x 130mm)
- Product weight: 9.25 lb (4.2kg)


CA Prop 65 Warning: This product contains nickel compounds within the vacuum tubes, which are known to the State of California to cause cancer. For more information, go to

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