PA66-S2 - Independent Bias Switching for PA66 or PX66


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PA66-S2 provides a panel switch plus the relays that fit onto PA66 or PX66 for easy and/or remote switching between cathode-bias and fixed-bias.

Where manual switches can be wired to PA66 for independent switching of the bias method, using PA66-S2 greatly simplifies this step. Power for the relays is readily attained from the AUX supply of any of London Power's PSU power supply kits for power amps, including PSU-TPA, PSU-10, PSU-25, PSU-50 or PSU-100.

PA66-S2 includes the relays that solder directly to PA66 or PX66. Two included panel switches provide independent control over the bias method for the tubes on PA66 or PX66.

One PA66-S2 is required for each PA66 and PX66 board.

Wiring diagram is included.

About London Power

London Power was founded in 1990 by Kevin O'Connor, after two decades of research into innovative audio amplification techniques. Kevin is an audio designer, author and speaker, known for his proprietary methodology called Power Scaling, and for his eleven books on audio subjects. Whether you seek amps, kits or information, you'll find useful answers here on not just the "how" but the "why" of audio amplifier design. Please enjoy the information on this site, and don't hesitate to contact us with questions.

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