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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.


Schematic for a three-speaker stereo arrangement which features a "null" in the center of its range.
AUDIO AMATEUR 3/1972 [Mar 1973] (v.3#3) pg. 24

Effects of speaker wire and fuse resistance on loudspeaker damping factor.
AUDIO AMATEUR 4/1972 [Jul 1973] (v.3#4) pg. 17
Added Info AUDIO AMATEUR 4/1973 [Aug 1974] (v.4#4) pg. 27, 28

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

A turn-on/turn-off/warmup transient eliminator is a time-delayed relay that installs between amplifier and speakers.
AUDIO AMATEUR 1/1978 [Mar 1978] (v.9#1) pg. 45

Tip on fabricating your own low level cables, power supply cables and speaker cables.
AUDIO AMATEUR 2/1982 [May 1982] (v.13#2) pg. 55

Better way to interface large, bulky speaker cables to terminals designed for smaller wire.
AUDIO AMATEUR 1/1983 [Apr 1983] (v.14#1) pg. 33

Use telephone cable to make your own "Super-Litz" speaker wires that are electrically comparable to commercial offerings and audibly better than ordinary Zip cord.
AUDIO AMATEUR 2/1984 [May 1984] (v.15#2) pg. 42

Tip on lowering the resistance of fuses used in audio power amplifiers or loudspeakers.
AUDIO AMATEUR 2/1984 [May 1984] (v.15#2) pg. 42

Tips on improving Magneplanar speakers. Looks at connections, fusing, wiring, and placement.
AUDIO AMATEUR 1/1987 [Jan 1987] (v.18#1) pg. 53

How to eliminate the adverse effects of loudspeaker cables by using four conductors instead of two.
AUDIO AMATEUR 2/1991 [Apr 1991] (v.22#2) pg. 62
Added Info AUDIO AMATEUR 1/1992 [Mar 1992] (v.23#1) pg. 56

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)

Speaker-cable impedance concerns. A look at the effect of speaker cable on the system.
AUDIOXPRESS Mar 2001 (v.32#3) pg. 62

Improved cable designs are used to connect a CD player to an amplifier and connect an amplifier to the loudspeakers.
AUDIOXPRESS Nov 2001 (v.32#11) pg. 80

Relays for loudspeaker protection. Everything you need to know about electromechanical relays to help you design better circuits to protect the speaker if the amplifier fails.
AUDIOXPRESS Aug 2002 (v.33#8) pg. 30

Damping loudspeakers in series. Effect of connecting two speakers in series is explored.
AUDIOXPRESS Nov 2002 (v.33#11) pg. 38
Correction AUDIOXPRESS Jan 2003 (v.34#1) pg. 61
Added Info AUDIOXPRESS May 2003 (v.34#5) pg. 57

How to wire a third speaker to a stereo.
BOYS' LIFE May 1978 (v.68#5) pg. 22

How to add a pair of remote speakers to a stereo system that is located on another floor.
CANADIAN WORKSHOP Dec 1986 (v.10#3) pg. 37

Remote security communicator. How to send control and voice/music signals hundreds of feet away through a common ac power line.
COMPUTERS & ELECTRONICS Apr 1983 (v.21#4) pg. 66

Speaker protector. This simple circuit will protect your stereo speakers from excessive DC voltages in the event of amplifier failure. Designed for use with solid-state amplifiers. Est. cost: $15.

Will beastie speaker cables improve your audio? Selecting speaker cables. Both heavy-gauge and traditional cables are compared.

Photoelectric automatic volume limiter for public address loudspeakers to prevent overload.
ELECTRONICS ILLUSTRATED Jan 1964 (v.7#1) pg. 100

Special transformer for adding a center speaker to a stereo system.
ELECTRONICS ILLUSTRATED Jan 1965 (v.8#1) pg. 72

Proper way to wire up extension speakers.
ELECTRONICS ILLUSTRATED Nov 1968 (v.11#6) pg. 70

Simple circuit to connect both the Left and Right outputs of a stereo amplifier to the same speaker.
ELECTRONICS NOW Jan 1993 (v.64#1) pg. 9

Problems of matching speakers to solid-state amplifiers. Includes details for adding loudspeaker to an existing hi-fi system.
ELECTRONICS WORLD Jan 1967 (v.77#1) pg. 23

How to add remote speakers to hi-fi stereo system.
ELECTRONICS WORLD Jan 1969 (v.81#1) pg. 31

Adding a third channel for improved hi-fi ambience. Derived from present two stereo channels.
ELECTRONICS WORLD Oct 1970 (v.84#4) pg. 31

Professional tips on connecting speakers. Considerations of impedance, switches, volume control, etc.
ELEMENTARY ELECTRONICS Jan-Feb 1967 (v.3#3) pg. 29

Install switch-selectable remote speakers around your house and yard in order to monitor CB, act as an intercom or provide entertainment.
ELEMENTARY ELECTRONICS Sep-Oct 1976 (v.16#5) pg. 78

Use cut-off bobby pins as clips to route small speaker or telephone wire along baseboard, molding, etc.
FAMILY HANDYMAN #298 May 1989 (v.39#5) pg. 111

Single-ended amplifier output impedance. Part 1. Includes advice on interfacing the amp with loudspeakers.
GLASS AUDIO 3/1997 (v.9#3) pg. 42

Single-ended amplifier output impedance. Part 2. Effects at low frequencies.
GLASS AUDIO 6/1997 (v.9#6) pg. 28

Make your speakers behave like resistors. Improve speaker quality with junk box parts in one evening.
HANDS-ON ELECTRONICS Dec 1986 (v.3#7) pg. 68
Correction HANDS-ON ELECTRONICS Mar 1987 (v.4#3) pg. 4

What you should know about home audio equipment. Includes information on improving your loudspeaker wiring system.
HOMEOWNER Apr 1987 (v.12#3) pg. 67

How to hook up a single speaker to the left and right channel outputs of a stereo system.
MODERN ELECTRONICS [1] Feb 1978 (v.1#1) pg. 17

Wiring diagram shows how to parallel a stereo output to feed a single loudspeaker.
MODERN ELECTRONICS [1] Oct 1978 (v.1#8) pg. 7

Adding extension speakers to a stereo system. Practical installation methods to obtain better sound reproduction and additional listening areas.
MODERN ELECTRONICS [2] Nov 1984 (v.1#2) pg. 44

Speaker overload indicator alerts listener to speaker signal input problems that can damage the transducers. Monitors your amplifier for (1) too much output, (2) too much distortion and (3) too much positive or negative dc voltage.
MODERN ELECTRONICS [2] Dec 1988 (v.5#12) pg. 34
Correction MODERN ELECTRONICS [2] Feb 1989 (v.6#2) pg. 7

Build a woofer guard. Delay circuit protects speaker cone from surges when amplifier is turned on or off.
POPULAR ELECTRONICS [1] Jul 1970 (v.33#1) pg. 49

Connect extension speakers to your hi-fi system without wires. A wireless transmitter sends music to loudspeakers over your existing ac power lines. Operating in FM mode, it results in good quality sound without much noise. Frequency response is 30-to-17,000-Hz. Est. cost: $20 for transmitter; $29 for receiver.
POPULAR ELECTRONICS [1] Jan 1976 (v.9#1) pg. 35

Failsafe circuit will remove ac power from your amplifier should a dc level appear across loudspeaker outputs. This will prevent direct coupled speakers from being accidently "burned out".
POPULAR ELECTRONICS [1] Sep 1978 (v.14#3) pg. 75

Build a speaker protection circuit which sets an upper limit on the decibel level which a sound system can generate. Est. cost: $10.
POPULAR ELECTRONICS [1] Aug 1979 (v.16#2) pg. 54

Electronic bass boost for woofers. Add an extra octave of clean bass with an active filter. Est. cost: $30.
POPULAR ELECTRONICS [1] Nov 1981 (v.19#11) pg. 47
Correction POPULAR ELECTRONICS [1] Mar 1982 (v.20#3) pg. 8

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

Tip on using an ohmmeter to determine which cables are attached to which loudspeaker.
POPULAR ELECTRONICS [2] Feb 1991 (v.8#2) pg. 28

The truth about speaker cables. A comparison of the various styles available.
POPULAR ELECTRONICS [2] Jul 1995 (v.12#7) pg. 46

Adding extension stereo speakers all through your house.
POPULAR MECHANICS Aug 1964 (v.122#2) pg. 160

Master selector for stereo speakers automatically maintains a proper impedance load when speakers are turned off and on. Allows selection of three stereo pairs and one monaural extension.
POPULAR MECHANICS Sep 1970 (v.134#3) pg. 140

Wiring and using a push-button selector for selecting up to five pairs of speakers in a hi-fi system. Est. cost: $40.
POPULAR MECHANICS Jun 1972 (v.137#6) pg. 114

Speaker switch for solid-state stereo amplifiers. Use it to select either or both of two pairs of speakers connected to an amplifier. Est. cost: $6.
POPULAR SCIENCE Aug 1967 (v.191#2) pg. 91

Simple technique for wraping and storing extra-long speaker wires on the back of the speaker.
POPULAR SCIENCE Sep 1989 (v.235#3) pg. 118

Speaker cables. How various types affect sound.
RADIO-ELECTRONICS Dec 1978 (v.49#12) pg. 60

Speaker overload protector circuit for lower-priced amplifiers.
RADIO-ELECTRONICS Dec 1981 (v.52#12) pg. 92
Correction RADIO-ELECTRONICS Aug 1982 (v.53#8) pg. 24

Circuit for a low-distortion audio limiter which attenuates sudden changes in volume. Use with any receiver. Ideal for use with earphones.
RADIO-ELECTRONICS Jul 1983 (v.54#7) pg. 74

Chart of recomended wire sizes when hooking up speakers. Shows the maximum wire length that can be used between the amp and the speakers so that line losses do not exceed 15% of the power.
RADIO-ELECTRONICS Jan 1986 (v.57#1) pg. 26

Tips on selecting speaker wire for a 100-watt system.
RADIO-ELECTRONICS Feb 1988 (v.59#2) pg. 12
Added Info RADIO-ELECTRONICS May 1988 (v.59#5) pg. 17
Added Info RADIO-ELECTRONICS Mar 1989 (v.60#3) pg. 15
Added Info RADIO-ELECTRONICS Jun 1989 (v.60#6) pg. 15
Added Info RADIO-ELECTRONICS Aug 1989 (v.60#8) pg. 12
Added Info RADIO-ELECTRONICS Dec 1989 (v.60#12) pg. 16

Tips on connecting an 8-ohm amplifier to 4-ohm speakers.
RADIO-ELECTRONICS May 1988 (v.59#5) pg. 13

Wireless stereo speaker system uses infrared communication.
RADIO-ELECTRONICS Aug 1988 (v.59#8) pg. 37, 66, 67

How to connect both the left and right outputs from a stereo amplifier to the same speaker.
RADIO-ELECTRONICS May 1990 (v.61#5) pg. 32

Will beastie speaker cables improve your audio? A comparison of heavy-gage speaker cables with conventional zip cord.
RADIO-ELECTRONICS Feb 1991 (v.62#2) pg. 50

Speaker protector. A simple circuit will protect your loudspeakers from excessive DC voltage in the event of an amplifier failure. Est. cost: $15 (kit).
RADIO-ELECTRONICS Aug 1991 (v.62#8) pg. 55
Added Info RADIO-ELECTRONICS Dec 1991 (v.62#12) pg. 14

Speaker cables. Results of tests performed on samples of new and exotic cables claiming to improve audio power transmission from amplifier to speaker.
SPEAKER BUILDER 2/1980 [May 1980] (v.1#2) pg. 6
Added Info SPEAKER BUILDER 3/1980 [Sep 1980] (v.1#3) pg. 43

Speaker protection schemes to prevent damage from overloads and transients. (1) Fuses. (2) Relay-controlled protector. (3) Peak-power limiting compressor. (4) Turn-on transient muter.
SPEAKER BUILDER 3/1980 [Sep 1980] (v.1#3) pg. 32

Evaluating the "zobel", a resistor and capacitor in series connected directly across the driver. It flattens out the frequency response by providing inverse characteristics.
SPEAKER BUILDER 4/1982 [Feb 1983] (v.3#4) pg. 14

Air tight cable connector for passing speaker leads through a sealed enclosure consists of a brass screw.
SPEAKER BUILDER 1/1983 [Jun 1983] (v.4#1) pg. 39

Level controls and balancing pads.
SPEAKER BUILDER 2/1983 [Aug 1983] (v.4#2) pg. 20
Added Info SPEAKER BUILDER 2/1984 [Jun 1984] (v.5#2) pg. 39
Added Info SPEAKER BUILDER 2/1991 [Apr 1991] (v.12#2) pg. 52
Added Info SPEAKER BUILDER 3/1991 [Jun 1991] (v.12#3) pg. 69

Tip on replacing Dahlquist DQ10 speaker level controls.
SPEAKER BUILDER 2/1983 [Aug 1983] (v.4#2) pg. 26

Tips on adding impedance compensation to the Madisound 10" woofer and the Audax 10" woofer. Also tips on fiberglass lining and resistive attenuators.
SPEAKER BUILDER 4/1983 [Dec 1983] (v.4#4) pg. 42

Tip on connecting 10-gauge wire to speakers and amplifiers.
SPEAKER BUILDER 1/1984 [Mar 1984] (v.5#1) pg. 34

Quasi-Zobel network. Modify a Heath IB-5281 RCL bridge to obtain a quasi-Zobel network.
SPEAKER BUILDER 1/1985 [Feb 1985] (v.6#1) pg. 33

Measuring and understanding the driver parameters of a dual-voice-coil subwoofer driver. Advice on series -vs- parallel wiring.
SPEAKER BUILDER 1/1985 [Feb 1985] (v.6#1) pg. 43

Tip on weaving your own speaker cord from 16 gauge cable.
SPEAKER BUILDER 4/1985 [Nov 1985] (v.6#4) pg. 58

Bi-wiring the LS3/5A Mini-Monitor speaker system. Provide about 70% of the sonic improvements of bi-amplifying, while using only one stereo power amplifier.
SPEAKER BUILDER 2/1986 [May 1986] (v.7#2) pg. 30

Using an array of small, identical drivers in a series or parallel arrangement allows you to obtain the efficiency and power handling of a single large driver. Crossover and wiring arrangements shown.
SPEAKER BUILDER 2/1986 [May 1986] (v.7#2) pg. 40
Added Info SPEAKER BUILDER 3/1986 [Aug 1986] (v.7#3) pg. 58

Tip on attaching a wire lug to speaker wire larger than 16 gauge.
SPEAKER BUILDER 3/1987 [Aug 1987] (v.8#3) pg. 46

Modifying the Polk model 10 speakers to extract more of the ambience inherent in a stereo recording.
SPEAKER BUILDER 4/1987 [Dec 1987] (v.8#4) pg. 32
Added Info SPEAKER BUILDER 4/1988 [Jul 1988] (v.9#4) pg. 62
Added Info SPEAKER BUILDER 6/1988 [Nov 1988] (v.9#6) pg. 60

Loudspeaker tune up. Tips on wiring, crossover, speaker stand, etc.
SPEAKER BUILDER 2/1988 [Apr 1988] (v.9#2) pg. 29

Comment on using L-type attenuation between crossover and tweeter.
SPEAKER BUILDER 2/1988 [Apr 1988] (v.9#2) pg. 54

Electronic time delay line for speakers. The delay line is installed between preamp and crossover and before the amplifiers.
SPEAKER BUILDER 3/1988 [May 1988] (v.9#3) pg. 15
Added Info SPEAKER BUILDER 5/1988 [Sep 1988] (v.9#5) pg. 55
Added Info SPEAKER BUILDER 6/1988 [Nov 1988] (v.9#6) pg. 74
Added Info SPEAKER BUILDER 5/1989 [Sep 1989] (v.10#5) pg. 55

Tip on using a spade lug at the end of speaker cable.
SPEAKER BUILDER 2/1989 [Mar 1989] (v.10#2) pg. 53

Servo-controlling the AR-1. Convert a subwoofer into a servo-mechanical speaker. Using feedback from a microphone mounted close to the driver voice coil to automatically control the power being delivered to the driver.
SPEAKER BUILDER 3/1989 [May 1989] (v.10#3) pg. 24
Added Info SPEAKER BUILDER 5/1989 [Sep 1989] (v.10#5) pg. 62
Added Info SPEAKER BUILDER 1/1990 [Feb 1990] (v.11#1) pg. 53
Added Info SPEAKER BUILDER 3/1991 [Jun 1991] (v.12#3) pg. 74
Added Info SPEAKER BUILDER 4/1991 [Aug 1991] (v.12#4) pg. 89
Added Info SPEAKER BUILDER 2/1992 [Apr 1992] (v.13#2) pg. 68

Semi-universal noninvasive speaker muting switch. Closes the relay connecting loudspeakers to amplifier about 5-seconds after amplifier is turned on. This prevents turn-on transients from reaching the speakers. Also works to prevent turn-off transients.
SPEAKER BUILDER 3/1989 [May 1989] (v.10#3) pg. 33

Switcher. Heavy-duty loudspeaker switcher allows independent switching of left and right channels to facilitate comparison testing of loudspeakers.
SPEAKER BUILDER 3/1989 [May 1989] (v.10#3) pg. 40

Tip on using "Phantom Flex", a 12-gauge flat wire, for speaker interconnect.
SPEAKER BUILDER 4/1989 [Jul 1989] (v.10#4) pg. 59

An acceleration feedback system. Two ways to improve the problematic low-frequency (woofer) response of dynamic speaker systems. This unique DIY article also includes notes, ideas, formulas and considerations.
SPEAKER BUILDER 1/1990 [Feb 1990] (v.11#1) pg. 10
Correction SPEAKER BUILDER 1/1991 [Feb 1991] (v.12#1) pg. 81
Added Info SPEAKER BUILDER 1/1991 [Feb 1991] (v.12#1) pg. 82
Added Info SPEAKER BUILDER 3/1991 [Jun 1991] (v.12#3) pg. 74
Added Info SPEAKER BUILDER 4/1991 [Aug 1991] (v.12#4) pg. 89
Added Info SPEAKER BUILDER 2/1992 [Apr 1992] (v.13#2) pg. 68

Measuring resistance and inductance of voice coils. Designing and using Zobel networks to make the impedance of a woofer look like a resistor.
SPEAKER BUILDER 2/1990 [Apr 1990] (v.11#2) pg. 50
Added Info SPEAKER BUILDER 1/1992 [Jan 1992] (v.13#1) pg. 73

Formulas to determine values for impedance equalization and values for series notch filters when two identical drivers are used together.
SPEAKER BUILDER 3/1990 [Jun 1990] (v.11#3) pg. 3
Added Info SPEAKER BUILDER 3/1992 [May 1992] (v.13#3) pg. 75

Contact basics. Tips on achieving the optimum in a loudspeaker's electrical contacts (wire connections).
SPEAKER BUILDER 3/1990 [Jun 1990] (v.11#3) pg. 24
Added Info SPEAKER BUILDER 6/1991 [Dec 1991] (v.12#6) pg. 67

Constructing high-quality plaited loudspeaker cable from 20AWG wire.
SPEAKER BUILDER 5/1991 [Oct 1991] (v.12#5) pg. 42

Cable and sound delivery. A look at the complexities of loudspeaker cable behavior, experimental findings, and magnetic considerations.
SPEAKER BUILDER 6/1991 [Dec 1991] (v.12#6) pg. 43

Driver attenuation for matching. Table gives the values of the two resistors required in an attenuator circuit in order to match individual driver sensitivities.
SPEAKER BUILDER 6/1995 [Sep 1995] (v.16#6) pg. 53

Make a better speaker cable that has low inductance, pleasing aesthetics and low cost ($.15/ft.) by using computer ribbon cable.
SPEAKER BUILDER 2/1996 [Apr 1996] (v.17#2) pg. 16

A cheap, hi-tech loudspeaker cable is fabricated from multiple twisted pairs of small-gauge, Teflon-insulated, high-purity copper wire (digital trunk line).
SPEAKER BUILDER 6/1996 [Oct 1996] (v.17#6) pg. 66
Added Info SPEAKER BUILDER 1/1997 [Feb 1997] (v.18#1) pg. 47
Added Info SPEAKER BUILDER 4/1997 [Jun 1997] (v.18#4) pg. 51

Directionality in speaker cables. Results of an investigation.
SPEAKER BUILDER 3/1998 [May 1998] (v.19#3) pg. 30

Improving the sound from an audio system. (1) Delivering good clean AC power. (2) Using speaker stands. (3) Installing good speaker cables.
SPEAKER BUILDER 5/1999 [Aug 1999] (v.20#5) pg. 60

Speaker cables. How to construct your own long cables with low resistance and low inductance.
SPEAKER BUILDER 7/1999 [Nov 1999] (v.20#7) pg. 38
Added Info SPEAKER BUILDER 2/2000 [Apr 2000] (v.21#2) pg. 46

Stretching your stereo. A few simple gadgets and techniques can help you put music in every room, and make your stereo truly remote-controlled. It involves running wires to remote speakers.
SUNSET Mar 1992 (v.188#3) pg. 122