HF-QS - Hifi Quiet Supply Design


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HF-QS is used to provide extraordinarily smooth DC voltages to solid-state power amplifier front-ends or preamplifier circuits.

  • active hum filtering
  • symmetric supplies
  • voltages limited only by capcitor selection
  • board size 2.6x1.2" 66x31mm

HF-QS provides filtering for both plus and minus supply rails all on one board. There is provision for HF-QS to also act as a voltage regulator, while retaining its hum-reducing performance.

The free version of this info package, HF-QS FREE (249KB), includes enough info for the hobbyist to make his own printed circuit boards using the following PDFs:

  • schematic
  • parts overlay
  • top foil
  • bottom foil
  • bill of materials

Click HERE to download HF-QS FREE.

HF-QS COMPLETE (753KB) includes all of the above info plus notes about how it works, how to adjust the filtering effects, how to use HF-QS as a regulator, along with Gerber and Excellon files for a professional PCB. HF-QS COMPLETE includes:

  • schematic
  • parts overlay
  • top foil
  • bottom foil
  • comprehensive notes - 4 pages
  • Gerber and Excellon files
  • safety notes

Click "Add to Cart" above to order HF-QS COMPLETE.

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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