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Detailed entries for one subject from the INDEX TO HOW TO DO IT INFORMATION.
Click on a see also (sa) or tracing (xx) to view detailed entries about a related subject.
The entries are in alphabetical order by magazine name and then in chronological sequence.
To obtain a copy of any magazine article contact your local public library or the publisher.


Controlling those volts and amperes. Improving the fidelity in your audio amplifier's DC power source. Design and construction of three regulated power supplies for audio amplifiers.
AUDIO AMATEUR 1/1971 (v.2#1) pg. 11
Added Info AUDIO AMATEUR 2/1971 [Nov 1971] (v.2#2) pg. 23
Correction AUDIO AMATEUR 4/1971 [Jul 1972] (v.2#4) pg. 13

Op amps for audio. Part 3. Regulated power circuits (RC filter, voltage regulator, power supply).
AUDIO AMATEUR 4/1974 [Apr 1975] (v.5#4) pg. 14
Correction AUDIO AMATEUR 2/1975 [Nov 1975] (v.6#2) pg. 38

The speaker saver. An overview of the problem of "speaker thump" when turning-on or turning-off a solid state audio amplifier. Includes a relay circuit to connect the amplifier sources and speakers only after a time delay on power-up, but to disconnect them immediately on power-down.
AUDIO AMATEUR 3/1977 [Aug 1977] (v.8#3) pg. 4
Added Info AUDIO AMATEUR 2/1978 [Jun 1978] (v.9#2) pg. 51
Added Info AUDIO AMATEUR 4/1987 [Nov 1987] (v.18#4) pg. 51

Improving the Dynaco Mark III tube amplifier's power supply through regulation and filtration.
AUDIO AMATEUR 1/1978 [Mar 1978] (v.9#1) pg. 32
Added Info AUDIO AMATEUR 3/1978 [Sep 1978] (v.9#3) pg. 55
Added Info AUDIO AMATEUR 4/1978 [Nov 1978] (v.9#4) pg. 52, 54
Added Info AUDIO AMATEUR 1/1979 [Feb 1979] (v.10#1) pg. 53, 55
Added Info AUDIO AMATEUR 3/1979 [Jul 1979] (v.10#3) pg. 62
Added Info AUDIO AMATEUR 3/1980 [Jun 1980] (v.11#3) pg. 51
Added Info AUDIO AMATEUR 2/1982 [May 1982] (v.13#2) pg. 51
Added Info AUDIO AMATEUR 4/1989 [Oct 1989] (v.20#4) pg. 57

A family of power amplifier regulated power supplies. Schematics for both positive and negative regulator circuits are included.
AUDIO AMATEUR 1/1980 [Jan 1980] (v.11#1) pg. 6
Correction AUDIO AMATEUR 4/1980 [Nov 1980] (v.11#4) pg. 63
Added Info AUDIO AMATEUR 5/1982 [Jan 1983] (v.13#5) pg. 40
Added Info AUDIO AMATEUR 4/1989 [Oct 1989] (v.20#4) pg. 62
Added Info AUDIO AMATEUR 2/1990 [Apr 1990] (v.21#2) pg. 66
Added Info AUDIO AMATEUR 3/1990 [Aug 1990] (v.21#3) pg. 57
Added Info AUDIO AMATEUR 3/1991 [Aug 1991] (v.22#3) pg. 46

Eliminate audible turn-on transients in low level units, preamps, equalizers, ... etc. by modifying the power supply so it turns on slowly.
AUDIO AMATEUR 1/1980 [Jan 1980] (v.11#1) pg. 40

Super storage for the 410 amplifier. Provide an extra 148,000 uF of capacitance for the Dynaco ST-410 power supply.
AUDIO AMATEUR 1/1981 [Feb 1981] (v.12#1) pg. 38
Correction AUDIO AMATEUR 2/1982 [May 1982] (v.13#2) pg. 50

Classic circuitry. Schematics of the (1) Acrosound 100 watt amplifier with the TO-350 transformer and (2) power supply for 100 watt ultra-linear amplifier. (Circa 1960).
AUDIO AMATEUR 4/1981 [Sep 1981] (v.12#4) pg. 56

Schematic for a vacuum tube voltage regulated power supply for an audio amplifier (Child's amplifier, circa 1964).
AUDIO AMATEUR 1/1982 [Jan 1982] (v.13#1) pg. 56

Circuit for a capacitance multiplier used as a power amp supply.
AUDIO AMATEUR 4/1982 [Oct 1982] (v.13#4) pg. 40
Correction AUDIO AMATEUR 1/1984 [Mar 1984] (v.15#1) pg. 54

Measuring power supply output impedance in audio applications. Part 1.
AUDIO AMATEUR 1/1983 [Apr 1983] (v.14#1) pg. 13

Measuring power supply output impedance in audio applications. Part 2.
AUDIO AMATEUR 2/1983 [Jun 1983] (v.14#2) pg. 20
Correction AUDIO AMATEUR 3/1983 [Sep 1983] (v.14#3) pg. 56

Power up. An overview of power supply design for high-quality audio amplifiers.
AUDIO AMATEUR 3/1983 [Sep 1983] (v.14#3) pg. 16

Circuit to control the charging rate of large supplementary capacitors added to a Dynaco 400 amplifier. This prevents a large current drain at turn-on.
AUDIO AMATEUR 5/1983 [Jan 1984] (v.14#5) pg. 40

Classic circuitry. Schematic for the Dynaco C-100 add-on Energy Storage System which expands the Dynaco 416's capacitive storage to enhance the power supply.
AUDIO AMATEUR 5/1983 [Jan 1984] (v.14#5) pg. 48

Make the right match. How to meet your amplifier's power supply needs. At look at how power supply impedance affects the output signal. Includes setups to measure the power supply's impedance.
AUDIO AMATEUR 3/1984 [Jul 1984] (v.15#3) pg. 14
Correction AUDIO AMATEUR 1/1985 [Jan 1985] (v.16#1) pg. 53
Added Info AUDIO AMATEUR 1/1985 [Jan 1985] (v.16#1) pg. 55

Upgrading the voltage regulator circuits in an Acrosound Stereo 120 amplifier.
AUDIO AMATEUR 3/1984 [Jul 1984] (v.15#3) pg. 50
Added Info AUDIO AMATEUR 4/1984 [Sep 1984] (v.15#4) pg. 52

Soft turn-on circuit for audio amplifiers equipped with large storage capacitors will prevent blown fuses, damaged switches, etc.
AUDIO AMATEUR 4/1984 [Sep 1984] (v.15#4) pg. 46

POOGE-3. How improving common-mode and power-supply rejection can improve the audible performance of your amplifier.
AUDIO AMATEUR 4/1985 [Oct 1985] (v.16#4) pg. 39
Correction AUDIO AMATEUR 1/1986 [Feb 1986] (v.17#1) pg. 50
Added Info AUDIO AMATEUR 4/1986 [Oct 1986] (v.17#4) pg. 48
Added Info AUDIO AMATEUR 1/1988 [Feb 1988] (v.19#1) pg. 48

Inductance for your supply design. The benefits of incorporating inductor input filtering in solid-state audio power supplies.
AUDIO AMATEUR 4/1987 [Nov 1987] (v.18#4) pg. 22
Added Info AUDIO AMATEUR 2/1988 [May 1988] (v.19#2) pg. 51

Tips on adding a regulated power supply to a Dynaco Mark II amplifier.
AUDIO AMATEUR 2/1988 [May 1988] (v.19#2) pg. 60

Troubleshooting fuse-blowing problems in the Marantz 9 tube power amplifier.
AUDIO AMATEUR 3/1989 [Aug 1989] (v.20#3) pg. 57

A power supply regulator for the ADCOM GFA-555 power amplifier.
AUDIO AMATEUR 4/1989 [Oct 1989] (v.20#4) pg. 34
Added Info AUDIO AMATEUR 1/1990 [Feb 1990] (v.21#1) pg. 59
Added Info AUDIO AMATEUR 2/1990 [Apr 1990] (v.21#2) pg. 62, 65
Added Info AUDIO AMATEUR 3/1990 [Aug 1990] (v.21#3) pg. 5, 52, 58
Correction AUDIO AMATEUR 4/1990 [Oct 1990] (v.21#4) pg. 53
Added Info AUDIO AMATEUR 2/1991 [Apr 1991] (v.22#2) pg. 68

Ground loops revisited. Troubleshooting improper power supply grounding in phono amplifiers.
AUDIO AMATEUR 3/1991 [Aug 1991] (v.22#3) pg. 30

Megafarad power supplies. How and why to avoid too much capacitance in a power supply.
AUDIO AMATEUR 4/1991 [Oct 1991] (v.22#4) pg. 44

An amplifier/speaker protection circuit. Fault condition protection circuit features turn-on delay with fast turn-off, amplifier offset shutdown, adjustable thermal shutdown, fault indicator light, and modular topology.
AUDIO AMATEUR 2/1993 [Jun 1993] (v.24#2) pg. 26
Added Info AUDIO AMATEUR 1/1995 [Jan 1995] (v.26#1) pg. 38 (An upgraded version)

Hafler DH220 low-level regulators. Adding regulated power supplies to a Hafler DH220 amplifier.
AUDIO AMATEUR 4/1993 [Dec 1993] (v.24#4) pg. 16

Measured RFI differences between rectifier diodes in simple capacitor-input power supplies. Includes a simple RFI test setup to measure rectifier diodes under a realistic load without introducing other variables.
AUDIO AMATEUR 1/1994 [Mar 1994] (v.25#1) pg. 26
Added Info AUDIO AMATEUR 3/1994 [Sep 1994] (v.25#3) pg. 46
Added Info AUDIO AMATEUR 4/1994 [Dec 1994] (v.25#4) pg. 47

Use of battery power to produce a noise-free DC power source for audio applications is discussed.
AUDIO AMATEUR 3/1994 [Sep 1994] (v.25#3) pg. 49

Regulators for high-performance audio. Focuses on low-level power supplies (+5 to +/-20 volts) with current drains of 300mA or less. Includes detailed design, testing, and performance information on output regulators. Part 1.
AUDIO AMATEUR 1/1995 [Jan 1995] (v.26#1) pg. 8
Added Info AUDIO AMATEUR 2/1995 [Jun 1995] (v.26#2) pg. 45, 47
Added Info AUDIO AMATEUR 4/1995 [Nov 1995] (v.26#4) pg. 38

Regulators for high-performance audio. Part 2.
AUDIO AMATEUR 2/1995 [Jun 1995] (v.26#2) pg. 20

Regulators for high-performance audio. Part 3.
AUDIO AMATEUR 3/1995 [Aug 1995] (v.26#3) pg. 20
Added Info AUDIO ELECTRONICS 4/2000 [Jul 2000] (v.31#4) pg. 8 (Improved version)
Correction AUDIO ELECTRONICS 5/2000 [Sep 2000] (v.31#5) pg. 42 (Improved version)

Report on the Marchand PM2 power amplifier kit and PS11 dual 40V power supply. Includes construction tips and specifications.
AUDIO AMATEUR 3/1995 [Aug 1995] (v.26#3) pg. 42

Regulators for high-performance audio. Part 4.
AUDIO AMATEUR 4/1995 [Nov 1995] (v.26#4) pg. 34
Correction AUDIO AMATEUR 1/1996 [Mar 1996] (v.27#1) pg. 50, 51
Added Info AUDIO AMATEUR 2/1996 [May 1996] (v.27#2) pg. 46

Using differential circuits in AC power supplies and amplifiers to effectively reduce hum and noise.
AUDIO AMATEUR 2/1996 [May 1996] (v.27#2) pg. 36

Simple "soft-charge" circuit for extra power-supply capacitors that have been added to an audio amplifier.
AUDIO AMATEUR 3/1996 [Sep 1996] (v.27#3) pg. 39

Unleash your AC power line. A look at the limitations of the 120-volt power supply in the typical house when used to drive a powerful audio system. Advantages of using 240-volt power are explored along with other options.
AUDIO ELECTRONICS 4/1997 [Aug 1997] (v.28#4) pg. 18
Added Info AUDIO ELECTRONICS 2/1998 [Apr 1998] (v.29#2) pg. 38
Added Info AUDIO ELECTRONICS 1/1999 [Jan 1999] (v.30#1) pg. 48
Added Info AUDIO ELECTRONICS 5/1999 [Sep 1999] (v.30#5) pg. 54

Calculating optimum snubbers. How snubbers work in audio power supply circuits. Formulas to determine values for the resistor and capacitor components.
AUDIO ELECTRONICS 1/1998 [Jan 1998] (v.29#1) pg. 26
Added Info AUDIO ELECTRONICS 3/1998 [Jun 1998] (v.29#3) pg. 38, 39

Simple circuit uses a single bicolor LED to indicate the status of split power supplies.
AUDIO ELECTRONICS 6/1998 [Dec 1998] (v.29#6) pg. 46

The A40M. A case study in audio amplifier design. Part 5. Power supply.
AUDIO ELECTRONICS 3/2000 [May 2000] (v.31#3) pg. 28
Added Info AUDIO ELECTRONICS 5/2000 [Sep 2000] (v.31#5) pg. 42
Added Info AUDIO ELECTRONICS 6/2000 [Nov 2000] (v.31#6) pg. 38

A start-up delay circuit for vintage amplifiers can be easily removed to restore the amp to original condition.
AUDIOXPRESS Aug 2001 (v.32#8) pg. 50

Phase inverting by transformers. How to use transformers and vacuum tubes to drive push-pull amplifiers.
AUDIOXPRESS Sep 2001 (v.32#9) pg. 40

Zen variations. Part 2. The Penultimate Zen's current source.
AUDIOXPRESS Jul 2002 (v.33#7) pg. 8

Zen variations. Part 3. A power-supply regulator suitable for the Zen amplifier projects.
AUDIOXPRESS Aug 2002 (v.33#8) pg. 16

How to salvage the DC to DC inverter circuit found in disposable flash cameras and use it in the power supply for tube amplifier projects.
AUDIOXPRESS May 2003 (v.34#5) pg. 46

Schematic of the Merit Coil & Transformer Corp. A-2997 output transformer designed for the Norman Crowhurst twin-coupled amplifier (circa 1957).
AUDIOXPRESS May 2003 (v.34#5) pg. 72

Audio system power controller applies and removes 110-VAC power to a pre-amp and two main amps to avoid turn-on or turn-off artifacts (audible thumps).
AUDIOXPRESS Aug 2003 (v.34#8) pg. 46

DC protection and switch-on delay for audio power amplifiers.
AUDIOXPRESS Sep 2003 (v.34#9) pg. 34

Tips on turning an audio amplifier with a soft switch on/off using an X-10 module.
ELECTRONIC HOUSE Apr 1997 (v.12#2) pg. 58

Basic circuitry for power-supply decoupling to prevent audio crosstalk.
ELECTRONICS NOW Oct 1992 (v.63#10) pg. 13

Looking at vacuum tube rectifiers in an audio amplifier's power supply. Exploring the hypothesis that replacing solid-state rectifiers with tubes can have sonic benefits. Guidelines on powering vacuum-tube style amplifiers.
GLASS AUDIO 2/1989 (v.1#2) pg. 13
Added Info GLASS AUDIO 3/1995 (v.7#3) pg. 51

On the nature of power supplies. Simplified theory and computer analysis looks at the "sound" emitted by audio power supplies which affect reproduction quality.
GLASS AUDIO 2/1990 (v.2#2) pg. 14

Filament/heater supply and regulator circuit that eliminates the noise and hum directly introduced from other heater supplies.
GLASS AUDIO 1/1992 (v.4#1) pg. 38
Correction GLASS AUDIO 2/1992 (v.4#2) pg. 54

Tips on removing or avoiding DC interference on the AC inputs to an audio power supply for a vacuum-tube amplifier. Includes tip on using rechargeable batteries to supply the power.
GLASS AUDIO 1/1993 (v.5#1) pg. 32

Improving the vacuum-tube slow turn-on voltage and constant-current heating circuits in preamp and power amp supplies.
GLASS AUDIO 1/1993 (v.5#1) pg. 38

Tip on calculating the correct capacitor value for use in a regulated HT power supply.
GLASS AUDIO 1/1993 (v.5#1) pg. 39

Standard circuit for extending an amp's tube life by taking 40 seconds to bring vacuum tubes to full power.
GLASS AUDIO 4/1993 (v.5#4) pg. 37

Report on e/j Bloom Associates, Inc. "IMagine" switch-mode power supply kit. Includes a modification to supply the vacuum tube heaters in your amplifier.
GLASS AUDIO 1/1994 (v.6#1) pg. 36

Purist tube-regulated power supply. Part 1. Design.
GLASS AUDIO 3/1994 (v.6#3) pg. 1

Soft-starting control system for a vacuum tube amplifier.
GLASS AUDIO 3/1994 (v.6#3) pg. 14
Correction GLASS AUDIO 1/1995 (v.7#1) pg. 38

Rectifying your drivers. Build a tube rectifier circuit to pass current to your audio amplifier once the tube is warmed up, but not before. This provides the slow-start which is beneficial to vacuum tube amplifiers.
GLASS AUDIO 4/1994 (v.6#4) pg. 20
Added Info GLASS AUDIO 3/1995 (v.7#3) pg. 55
Added Info GLASS AUDIO 3/2000 (v.12#3) pg. 70
Correction GLASS AUDIO 5/2000 (v.12#5) pg. 50
Added Info AUDIOXPRESS Jan 2001 (v.32#1) pg. 100

Purist tube-regulated power supply. Part 2. Construction and testing.
GLASS AUDIO 4/1994 (v.6#4) pg. 22

Tip on using NTC resistors in series with the primary winding of the power transformer to provide a soft start.
GLASS AUDIO 4/1994 (v.6#4) pg. 40

Soft-start for power tubes. A power switch modification that turns the power amp on or off without extra tube stress.
GLASS AUDIO 3/1995 (v.7#3) pg. 30

Tips on reducing filament hum when restoring old vacuum tube amplifiers by changing the power supply transformer and/or changing the DC heater supply ground scheme.
GLASS AUDIO 2/1996 (v.8#2) pg. 44
Added Info GLASS AUDIO 2/1997 (v.9#2) pg. 64

Single-channel power-supply circuit to improve the performance of an ST70 Dynakit stereo amplifier.
GLASS AUDIO 2/1996 (v.8#2) pg. 50

EZ start power controller. A stand-alone soft start power controller for audio amplifiers (or other electronic equipment) slowly ramps up the line voltage from 0% to 97% in 25 seconds and then goes to 100%. A good way to extend the life of vacuum tube equipment.
GLASS AUDIO 3/1996 (v.8#3) pg. 54
Correction GLASS AUDIO 5/1996 (v.8#5) pg. 62

Big mother power supply. A large, dual/mono, one-chassis, cost-no-object amplifier power supply that includes a regulated circuit board for the small tubes and the screen grids of the output tubes. Two versions described.
GLASS AUDIO 2/1997 (v.9#2) pg. 46

Ripple reduction in full-wave center-tapped power supplies. A simple, low-cost modification that allows reduction of the power frequency ripple component by about 20 dB.
GLASS AUDIO 3/1998 (v.10#3) pg. 12

Smart soft-start and standby circuit for tube amplifiers. A simple circuit, but requires some knowledge of electronics and your amplifier's operation in order to install it.
GLASS AUDIO 3/1998 (v.10#3) pg. 22

Vacuum diode models and PSpice simulations. Using computer simulation in the design phase to select the correct vacuum diode as a rectifier element in audio amplifier power supplies.
GLASS AUDIO 4/1998 (v.10#4) pg. 38
Added Info GLASS AUDIO 2/1999 (v.11#2) pg. 57

Tips on fixing a diode-switching noise problem on audio power supplies.
GLASS AUDIO 6/1998 (v.10#6) pg. 76

Correct way to wire the vacuum tubes in amplifiers to guarantee that all tubes will receive the same heater supply voltage.
GLASS AUDIO 1/1999 (v.11#1) pg. 67

Audio classroom. Reprints of 1950's articles focuses on the basics to help you better understand tube design. Power supplies. Part 1. Power transformers and rectifiers.
GLASS AUDIO 3/1999 (v.11#3) pg. 48
Added Info GLASS AUDIO 2/2000 (v.12#2) pg. 69

Audio classroom. Power supplies. Part 2. Power-supply filters.
GLASS AUDIO 4/1999 (v.11#4) pg. 44

Techniques to reduce hum more efficiently in high-voltage power supplies fitted with a filter choke.
GLASS AUDIO 4/1999 (v.11#4) pg. 67

Audio classroom. Power supplies. Part 3. Decoupling networks and voltage regulation.
GLASS AUDIO 5/1999 (v.11#5) pg. 56

Diode ripple killer. Audio amp power supply circuitry which uses a diode in line with the first voltage-dropping resistor to prevent any backward flow of supply voltage caused by a large current pulse being drawn.
GLASS AUDIO 6/1999 (v.11#6) pg. 78
Added Info GLASS AUDIO 4/2000 (v.12#4) pg. 58

Delay timer circuit for a stereo amplifier eliminates the loud "pop" caused when power is turned on by keeping the loudspeakers off-line for about 4 seconds.
POPULAR ELECTRONICS [2] Mar 1990 (v.7#3) pg. 26

Timer-controlled turn-off delay circuit for a tape deck/amplifier arrangement which eliminates audio thump.
POPULAR ELECTRONICS [2] Apr 1993 (v.10#4) pg. 73
Correction POPULAR ELECTRONICS [2] May 1994 (v.11#5) pg. 89, 28