Popular Power Supply & Regulator Topologies for Hi-Fi Audio:
Including 3-Terminal, Jung, Sulzer, Shunt, Linear, Series. SMPS, etc.

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Below is what I believe to be a fairly comprehensive -- and growing -- list of modern voltage regulators, CCS's (constant-current sources) and power-supply designs. These high-performance designs are intended to be used for hi-fi audio and have been posted on myriad private and commercial web sites and Internet forums.

Please note: I do not sell products nor do I offer kits. Most of the "[products for sale]", noted below, are known to me only through web pages and forum group discussions. I only list commercial-product web sites to show you examples of specific designs or design execution. I have not purchased nor built most commercial products. Hence, I cannot confirm/deny the performance or reputation of any product. As a DIYer, I would encourage you to: (a) learn as much as you can about these regulators; (b) build some of the simpler designs; and (c) if you are pleased with your results, try building one of the more challenging projects. Purchase ready-made products only as a last resort.

Power Supplies (transformer + diodes + filter capacitors + regulator)

Diodes (for rectifiers and bridges)

  • soft + fast recovery rectifier diodes are best
  • other recommended rectifier diodes
    • low power: BYV-type (Sinterglass)
    • medium power: 8A HFA-type HEXFRED from International Rectifier
    • high power: 25A HFA HEXFRED, and the 25/50A FRED diodes from Infineon

Capacitors (filter, bypass)

  • Low ESR (Equivalent Series Resistance): low and medium power: Panasonic FC and FM, ELNA CERAFINE and Nichicon are capacitor brands to consider; electrolytic caps show increasing impedance at high frequencies (e.g. above 10kHz), so it is a good idea to parallel the electrolytic with film caps.
  • Choosing and Using Bypass Capacitors

Snubbers and Dampers

  • Snubbers: calculate best snubber values first for resistor, Rs, and capacitor, Cs. Install on power transformer secondary.
  • Damper: Install between transformer secondary (AC) and rectifier bridge and between bridge (and main and main regulator. Use low-value / high power resistor (0.5 to 5.0 ohms). Carbon best because of very little inductance (do not use wirewound). Power rating based on particular current and resistance value: P=I2R

Regulators (Linear: Series and Shunt)

Constant Current Sources (CCS)

  • Paul Hynes CCCS -- a "high-power [cascode] current-source module [which] has been designed for precision constant current source applications requiring high impedance over a wide bandwidth" [products for sale]
  • Peufeu's regulator design (See "Feeding the shuntregs" on this page)
  • PDK Shunt Regulator (uses CCS: The PDK Shunt regulator is a basic opamp-shunt using: (1) a three-terminal device as a constant-current source, (2) an opamp with a voltage reference for control, and (3) a power transistor as the sink device.)
  • Current Source on Wikipedia

Switching-Mode Power Supply (SMPS)

Battery Power Supplies

  • Articles and References
  • Examples
    • DDDAC.de [a private hobbyist in Germany discusses battery power for his digital-to-analog converter (DAC))
    • LessLoss.com [a small, commercial DAC company using a hybrid battery power supply; battery powers the digital section while rectified mains power the analog section]
    • Peter Burke's Audio Pages: Peter uses battery power exclusively for this DAC (a non-oversampling topology based on designs at DDDAC.de

Notes

(1) Martin from Acoustica.org.uk notes the following about the Flea regulator:

The flea didn't really start with the overall topology considered, but from the other end - the thought that in a regulator, for very small load currents only, the error amplifier could provide all the output current required. Using modern high performance op-amps could give exceptionally low output impedance across the audio band, exceptionally low noise - and wide bandwidth. So the flea started from there as a low-cost diy circuit that could be worth investigating.

Adding support circuitry to make it work at all owes much to the Sulzer reg in terms of keeping raw PSU noise out of the error amp and voltage reference, without the elaboration of Walt Jung's development of Mike Sulzer / Jan Didden's work.

The flea idea can be made to work as a shunt regulator rather well, but since its a bad idea to have high dissipation in the opamp, we stuck with a standard series regulator layout.

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Updated: Thursday, 2016-12-22 17:40 PST