hand made quad 405 amps

Quad not only made electrostatic speakers in the 70’s. They made a 100 watt class A amp specifically to drive them. Naturally it would be a crime to drive them with anything but this amp. thankfully the design has been replicated in china and even improved upon. they can be ordered as a kit on ebay. The listing wasnt especially clear, and the price was alarmingly cheap, leading to me ordering twice as many as i required. but we built them all the same, and im sure in time i will find a way to use them for something good.


they started making these in 1975, They make a perfect introduction to soldering with those massive components.


Some other kits included these excessive bridge rectifiers and capacitor arrays to provide ample dc power.




future work:

  • I still need to build enclosures for these ( perhaps a nice job for the techshop water jet )
  • I may make one unit old school monobloc and another stereo unit combining a preamp giving me a chance to experiment with digital potentiometers.


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