PA66-S1 - Global Bias Switching for PA66 or PX66


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PA66-S1 provides a panel switch plus the relays that fit onto PA66 or PX66 for easy and/or remote global switching between cathode-bias and fixed-bias.

Where manual switches can be wired to PA66 for global switching of the bias method, using PA66-S1 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-S1 includes a panel switch plus the relays that solder directly to PA66 or PX66. Add our PA66-CR Cathode-Bias Switching Relays for each PX66 added to include these tubes in the global bias switching.

See PA66-S2 for independent bias switching with relays plus two panel switches included.

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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