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Aici aveti la dispozitie 515 trimiteri catre pagini audio si scheme.

1. Analog Music Zone Guitar Effects Schematics - efecte pentru chitara, compresoare, efecte de microfoane
2. Andrea's projects - circuite si documentatie
3. Audio Designs Guide
4. Audio Electronic Design - circuit hi-fi in limba Franceza
5. Audio Electronics Page - apmplificatoare, preamplificatoare, surse de alimentare
6. ESP A- from ESP Audi Foarte multe proiecte audio
7. Pro Audio Equipment Schematics Page - Alan Garren's excellent listing of vintage gear schematics including API, UREI, Altec, RCA and more
8. The Do-It-Yourself Audio Corner - cum sa-ti faci boxe
9. 10 Watt IC Power Amp - realizat cu TDA2030
10. 20 Watt IC Power Amp - bazat pe LM1875
11. 1.5V AF Amplifier - un amplificator foarte micut alimentat de la o baterie de 1,5v
12. 22 Watt Audio Amplifier - amplificator stereo foarte simplu realizat cu TDA1554
13. 2 Watt Amplifier -amplificator cu distorsiuni foarte reduse realizat cu componente discrete
14. 8 Watt Audio Amp - bazat pe LM383
15. A HIFI class D audio power amplifier - The purpose of this site is to share a pulse-width modulating class D audio power amplifier design with the world, in order to involve people that have an interest in this kind of technology. This is in effect an "open source project", i.e. the design is open and free, and those that have the interest and ability, are encouraged to feed back back into the project.
16. Cheap 10 W amp - based on TDA2003 IC
17. Cheap thingies to help you make some racket - small amplifier circuits using many amplifier ICs, from few watts to 200W
18. DIY Class-A Audio Amp - Proiect cu amplificator de 15W in casa A
19. Emitter-follower-power-amplifier - amplificator de foarte mica putere si foarte simplu
20. Hiraga Le Classe A 20W
21. Hybrid Amplifier "Surt" - amplificator cu tuburi in calasa A
22. Lidström Improved ZEN i - Amplificator in calasa a cu FET
23. Low distortion audio amplifier - amplificator de 30w cu distorsiuni foarte reduse
24. Low Power Audio Amplifier - facut cu LM386
25. New Audio Amplifiers with Current Amplifier Outputs - principiul de functionare a unui amp de 10W , other designs up to 75W
26. Power amplifier has transient rail-to-rail swing - special common-drain MOSFET-based power op amp circuit
27. anken Hybrid Audio Power Amplifier Data - technical data and application circuits for 10-50W amplifiers
28. Simple Class A Amplifiers - a 10W design by J. L. Linsley Hood
29. The 2-Channel Power Amplifier: Design and Testing - 4W amplifier based on NTE 1606
30. The Pass Zen Amplifier - 10 Watts of Single-Stage Single-Ended Class A
31. Zen Revisited poweramp - 10 Watts of Single-Stage Single-Ended Class A solid-state amplifier
32. 100W RMS Amplifier
33. 100 W Amplifier
34. 120 Watt Vertärker - Amplificator de putere 120W
35. 200 Watt Lateral Mosfet Amplifier - general purpose symmetrical MOSFET design for power between 50 Watts to 200 Watts into 8 Ohms
36. 50 Watt Amplifier - amplificator usor de construit de 50 wati
37. 60 Watt Into 8 Ohms Power Amplifier - a simple amp to build, uses commonly available parts and is stable and reliable
38. 75W Power Amplifier - AKSA is a highly refined push pull solid state stereo amplifier of 75W per channel
39. Ampli MOSFET - DIY high power MOSFET amplifier 200 Wrms 8 ohms - 350 Wrms 4 ohms
40. Cheap thingies to help you make some racket - small amplifier circuits using many amplifier ICs, from few watts to 200W
41. El-Cheapo - Amplificator foarte simplu de 60W
42. N-Channel Power MOS- quasi complementary HEXFET N - Channel Power Amplifier that gives 260 Watts RMS into 8 Ohms and over 400 Watt RMS into 4 Ohms, check also N-Channel Amplif
43. New Audio Amplifiers - many amplifier and accessory circuits
44. New Audio Amplifiers with Current Amplifier Outputs - basic 10W design, other designs up to 75W
45. P400 hi-fi high end audio power amplifier - amplifier with 382W to 8 ohms power rating, can drive speakers at 2-16 ohms range
46. Pass Laboratories DIY Projects - mai multe proiecte de amplificatoare
47. Power amplifier subcircuit hoy the UHER CV-140 amplifier
48. SDS Labs Schematics - solid state class A amplifiers
49. Single Chip 50 Watt / 8 Ohm Power Amplifier - uses LM3876 hifi amplifier IC from National Semiconductor
50. Single Ended MOSFET Po- uses HEXFET "mosfet" transistors and develops over 50 Watts RMS into 8 Ohms, check also Suitable PSU for the SE Two Stage Power MOSFET Am
51. Symmetrical Output Amplifier - FET amplifier with power rating of 230 Watts RMS into 8 Ohms Per Channel and 400 Watts RMS into 4 Ohms Per Channel, first published in Silicon Chip Magazine in June 1994
52. The Leach Amp - 120W power amplifier, latest update of the "Low TIM Amplifier", claimed to be a very good sounding design
53. The Leach SuperAmp - 270 watt Double Barreled Amplifier published in Audio magazine
54. The LM12 - chip which can be uased ot make simple 80W amplifier
55. Professional has full circuit diagrams of some of their PA amplifiers in their technical pages, power ratings from 2x80W to
56. service manuals and circuit diagrams of some of their amplifiers
57. Renkus-Heinz Schematics
58. 20 Watt Power Amplifier - designed to be used as car amplifier
59. Car amplifier information and schematics
60. Car Amplifier Schematic
61. Car Audio Schematics - car amplifiers
62. Car tube pre amplifier
63. Do It Yourself - This article is for those who wants to make their own car amplifier. The basics of calculation will be discussed below. If you have understand it you will be able to make car amplifier based on article by Mr. T. Gi
64. Bridging Adaptor For Power Amplifiers
65. DIY Massive Heatsink Case - suitable for high power amplifier or class A power amplifier
66. Loudspeaker Protection and Muting
67. Loudspeaker Protection circuit - DC protection circuit
68. Power Follower with Dinamic Current Source by Reinhard Haffmann - less wasted power than true class A but not as good sound
69. Power Amplifier Clipping Indicator
70. Speaker protector
71. A DIY Headphone-Amplifier with Natu- check also An Enhanced-Bass Natural Crossfeed
72. An Acoustic Simulator for Headphone Amplifiers - a simple RC filter that creates a more realistic sound image in headphones by electronically mimicking spatial hearing with "shaded" interchannel crossfeed
73. Build These Noise-Canceling Headphones - plus Binaural Microphone Headset, Audio Probe, and Parabolic Microphone
74. Designing an Opamp Headphone Amplifier - mai multe exemple de amplificatoare
75. HeadBanger Headphone Amp Construction Kit
76. Headphone Amplifier - designed for Sega Megadrive, but can be used with other line level signal sources, Originally published in ETI, December 1994
77. Headphone Amplifier from SDS Labs - uses a push-pull Class A MOSFET output stage, being driven by an op-amp
78. HeadWize Projects - many headphone amplifiers and related circuit
79. Kumisa Mk. II - DIY headphone amplifier project using AD844 and some special transistors
80. SDS Labs Headphone Amp - solid state amplifier
81. Stereo - takes input from one audio power amplifier and drives many headphones vith adjustable audio level, available as a kit from
82. Top-Level OTL Tube Headphone Amplifier
83. HJ-4P Professional headphone distribution box - drives up to 4 headphones from a single amplifier, has volume control and mono switch, product datasheet with circuit diagram in pdf format
84. HJ-6 Standard headphone distribution box - drives up to 6 headphones from a single amplifier, product datasheet with circuit diagram in pdf format
85. 100W Guitar Amplifier
86. Cool Schematics - solid state and tube guitar amplifier circuits
87. ALL-FET MC- phono preamp with 54 and 64 dB gain and RIAA accuracy is better than 0.2dB, from Borbel
88. A Pocket Headphone Amplifie - portable headphone amplifier for testing purposes using Burr-Brown OPA132 opamp in a non-inverting configuration, powered with 9V battery

1. Audio Preamp - simple preamp for electric guitar or microphone
2. Bride of Zen preamp - a very simple line-level preamplifier which contains just one medium-power MOSfet per channel
3. Fender Pre-amp with Horizonal Tube Mounting
4. Hi-Fi Preamplifier
5. High quality preamp (STUDER)
6. Hiraga MC -Moving Coil förstärkare
7. IC Phono Stage Design
8. Kaneda Linjeförsteg - includes phono and line inputs
9. Mic-Pre Pan Pot Circuit
10. Simple Car Preamplifier and Artificial Earth
11. Simple Guitar Preamplifier
12. Power Amplifier Design Guidelines
13. Cool Audio - application notes on PWM amplifiers
14. LM12CL - very compact IC for making good quality 80W audio amplifier, this IC has been used in some high quality active loudspakers
15. 25L6 Amp - design without a power transformer
16. A hybrid amplifier using a 5687 tube and Magnatec PowerMosFets
17. Ampage - tube amps and music electronics
18. Aren's Attic Tube amplifiers - 1626 SE amplifier, ECL86 SE amplifier and tube links
19. Bob's Music/Vacuum Tube Audio / Electronics page - many amplifier circuits
20. Build a tube amplifier - articles from HiFi magazine (in Finnish)
21. Car tube pre amplifier
22. Dynaco Mark 3
23. Dynaco stereo 70
24. Experimental SE Pre-Amplifier - single-ended tube preamplifier
25. Klassiskt 300B slutsteg
26. Klaus Schiffer's audio web site - tube amplifiers and tube information
27. KTA/KSA High End Tube Audio - many tybe amplifier projects
28. Les projets en cours - tube amplifiers
29. Musical Instrument Tube Amp Building, Maintaining and Modifying FAQ
30. Pure A class - 15W pure A class and push-pull
31. SDS Labs Schematics - solid state class A amplifiers, headphone amplifier, vacuum tube amps
32. Sheldon's Audio Designs - audio DACs and tube amplifiers
33. Soft start for power tubes
34. The Preamplifier - tube amplifier that features relay input selector, µ-follower linestage, balanced RIAA amplifier, DC heater supplies, and shunt regulator for the RIAA power
35. Tube Guitar Amp
36. Tube Buffer for CD Player
37. Tube Line-Stage Design - pdf file
38. Tube Microphone Preamplifiers V72 (Telefunken/Siemens/Maihak/TAB) - information about the amplifier and the schematic
39. Vintage Quad equipment circuit diagrams
40. Quad 22 - circuit diagram of commercial tube amplifier
41. Zero Feedback Stereo Pre-Amplifier with Balanced & Unbalanced Inputs and Outputs
42. Phantom Power Supply Circuit - A power supply for adding 48 volt phantom power to microphone preamps
43. Regulated 12 Volts DC Power Supply for Vacuum Tube Heaters - this 7812 based circuit circuit can be used with low-hum audio applications such as microphone preamps and for other applications that require well regulated 12 volts
44. Regulated Vacuum Tube Power Supply - regulator de tensiune cu tuburi 250-300 VDC
45. 3 Line Mixer -very basic circuit built around one transistor
46. 6 Input Mixer - 3 intrari de linie si 3 intrari de microfon
47. Active audio mixer with pan-control - This circuit is the mixing part of an audio-mixer.
48. Advanced- good article on large audio mixer design, read also Noise & Headroom in
49. An Automatic MicropAudio mixer for Ramsey FM10 transmitter: description, schematic also in Postscript
50. Audio mikseri - simple three channel audio mixer, text in Finnish
51. High Quality Sound Mixer - very ambitious and expected to be very expensive mixer project, modular design
52. Microphone Mixer - designed for three dynamic microphones
53. Portable 20 Watt Mixer/Amplifier - portable amplifier and mixer which will run from a standard 12V battery and liven up any outdoor event
54. Simple 4-input mixer
55. Simple audio mixer for two signal sources
56. Simple audio mixer design ideas
57. Single capacitor powers audio mixer - micropower and low-voltage op amps allow you to build high-performance analog-signal processors that require no batteries or wall transformers, this simple mixer is powered using one large capacitor such as a Supercap or Dynacap for some time
58. Stage and Recording Mixer - full featured modular mixer design
59. Stereo Mixer - can mix four separate audio inputs to one mono or stereo output signal
60. A Two-Channel Noise Gate
61. An Unbalanced Mute Circuit For Audio Mixing Channels - schema de utilizare in format PDF
62. A New Balanced Audio Input Circuit for Maximum Common-Mode Rejection in Real World Environments - 109KB PDF file
63. Audio Transformers - notes on using audio transformers for balanced signal interfacing
64. Additional RFI Protection for Line Input Circuits - 8KB PDF
65. External Isolation Transformer Box for Mackie (and other) Mixers Eliminates RFI Problems
66. High CMRR Balanced Interface for Crystal 18 or 20 Bit A/D Converters - pdf file
67. Internal Modification to Mic Inputs of the Mackie 1604 Mixer Eliminates RFI Problems
68. Instrumentation or true balanced input differential amplifier
69. JT-6110K-B at Input Stage for Crystal A to D Converters - high performance transformer balanced input stage for Crystal A/D converters, pdf file
70. JT-11P-1 Balanced Tube Line Input Stage
71. JT-11SSP-6M as Input Transformer for Crystal CS5367 A/D Converter - transformer balanced passive input circuit for CS5367 A/D converter, pdf file
72. JT-16-A Improves Performance of SSM2015 Mic Preamp IC
73. JT-16-A Improves Performance of SSM2017 Mic Preamp IC
74. JT-MB-C in Low Noise, High Isolation Line Receiver for Low-Z Sources
75. JP-11P-1 Input transformer improvement for electronically balanced input
76. Jensen Transformers Application Schematics - many circuit examples with transformers
77. JT-MB-C Isolates both Mic and Line Inputs of Inexpensive Mixer
78. JT-MB-C Mic Input Isolation for Mackie Mixers
79. JT-MB-C "Real" Mic Inputs & Phantom Power for Sony DAT
80. Making Differential Probes - for sensing audio signal voltages across devices which are not ground referenced
81. Simple differential amplifier - opamp balanced input circuit with unity gain and common mode rejection adjust
82. Subtleties count in wide-dynamic-range anal- article on balanced input designing with some example circuit topologies, article from EDN m
83. 12 dB Amplifier and High Current Line Driver with DC Servo
84. 20 dB Amplifier and High Current Balanced Line Driver
85. High Output Line Driver for Single Ended Power Supply - pdf file
86. JT-11-BM High Level Differential IC Output Stage with DC Servo
87. JT-11-BM High Level High Current Differential Output Stage with DC Servo
88. JT-123-S Line Driver with Feedback Around the Transformer
89. JT-123-BL High Level Low Impedance Differential Output Stage with DC Servo
90. Low Noise version of High Level Output Stage in 1031 - pdf file
91. Mixed feedback drive circuits for audio output transformers - using feedback eliminates transformer distortion and primary resistance
92. Non-inverting amplifier - opamp circuit which provides 15 dB gain and option for balanced output
93. Simple 0 to 24 dB Gain Amplifier and Balanced Line Driver - 18KB PDF
94. Balancing Acts - balanced and unblanced interface circuits using tubes
95. Balanced Line Driver & Receiver
96. Balanced Line Inputs/Outputs for Silicon Graphics Workstations - balancing using transformers
97. Balanced Line Technology - information article and example circuits for both input and output
98. Bridging Line Amplifier - transformer balanced input and output with amplifier in between
99. Transfomers for audio interfacing - discussion on using audiop transformers in equipment interconnections, read also
100. Line-level transformers in High-End Audio
101. Zero Feedback Stereo Pre-Amplifier with Balanced & Unbalanced Inputs and Outputs - tube circuit
102. Grounding and shielding in balanced inputs and outputs which are transformer coupled
103. JT-11-YZPC in Unbalanced Long Line Driver/Isolator
104. Long Lines Driver - high current output configuration is ideal for use as a transformerless long lines driver
105. Black Box Circuit - a 40dB pad/100:1 attenuator for running spaker output to DI-box, so if you put 100 Watts in you'll get around 275 mVolts out
106. AV-1 Tech Sheet (Direct box,) - DI-box product datasheet which includes full circuit diagram, has line level and speaker level inputs, pdf file
107. AV-1PV Tech Sheet - DI-box with line level and speaker level inputs, with input volume control, data sheet with circuit diagram, pdf file
108. CB-1 Direct Box - unixersal DI-box product which works with guitar and keyboards, product datasheet with circuit diagram in pdf format
109. DB-1 Direct Box - DI-box with instrument and speaker level inputs, product datasheet with circuit diagram in pdf format
110. DB-4 Direct Box - four channel DI-box with keyboard or dum machnine inputs, product datasheet with circuit diagram in pdf format
111. Direct Injection Box for Recording & PA Systems - passive and active DI-box designs
112. Jensen Direct Box Transformers - data sheets have example circuit diagrams
113. JT-DB-E Standard Musical Instrument or Synthesizer "Direct Box"
114. JT-10KB-D Isolates and Converts Speaker Drive to Line Level
115. JT-11-FL provides Isolated Line Output from Guitar Amplifier
116. JT-11-FL Isolates & Converts Guitar Amp Speaker Out to Line Output
117. JT-11P-1 Conversion of Unbalanced Input to Balanced
118. JT-DB-E Full-featured "Direct Box" Application Schematic
119. JT-DB-E "Direct Box" for Very High Level Signals - takes high level line signal and outputs balanced microphone level signal
120. JT-DB-E Standard Musical Instrument or Synthesizer "Direct Box"
121. PO-26 Passi- circuit diagram of Sescom PO
122. Direct Injection Box for Recording & PA Systems - passive and active DI-box designs
123. Electric Crayons, Anyone? (A Vacuum Tube Microphone Preamp / Direct Box Project) - published in January97 EQ Column
124. Mike Pads and Other Small Gadgets - includes Active Direct Box circuit
125. JT-11B-1 + "Phantom" Buffer Provide Balanced Guitar Output
126. JT-11P-1 in 4-Way Active "Guitar Splitter" - from one guitar to up to 4 guitar amplifiers

1. JT-10B-D Used in Line Level 2-Way Splitter/Isolator - active line level splitter circuit with input and output isolation
2. JT-11P-1 in 2-Way Passive "Guitar Splitter" - from one guitar to two guitar amplifiers
3. MS-2 Mic Splitter - send signal from one microphone to two mixers, product datasheet with circuit diagram in pdf format
4. MS-82P Microphone Splitter with Phantom Power Buss - 8 channel microphone splitter which can inject phantom power to microphone, product datasheet with circuit diagram in pdf format
5. PO-25 Kit 1 x 3- circuit diagram of Sescom PO
6. Theory and Construction of Mic "Splitters" - 5 page booklet in pdf format
7. Transformer Coupled Splitter - active amplified transformer isolated signal splitter that enables hum-free connection of one guitar to more than one amp as well as having a direct output
8. IT-1 Inline 600/600 ohm line transformer - audio signal isolation transformer, product datasheet with circuit diagram in pdf format
9. IT-4 four channel isolation transformer unit - audio signal isolation transformer, product datasheet with circuit diagram in pdf format
10. JT-11-DM Basic Hum Stopper Transformer isolation box - simple isolator for 600 ohm balanced audio lines
11. JT-11P-1 Unbalanced Automotive or Consumer Application - isolation transformer box for unbalanced consumer audio line signals
12. JT-11P-1 Conversion of Unbalanced Input to Balanced
13. JS-11SSP-6M 150 ohm line to 600 ohm load application - isolation transformer with impednace conversion
14. JT-11SSP-6M 600 Ohm Line Isolation Application - isolation transformer for 600 ohm balanced audio line
15. JS-11SPP-6M 600 ohm line isolator with line termination switch - for used with long 600 ohm lines which need termination
16. JT-11SSP-6M Universal Patchbay Isolation Application - for use with professional low impedance sources and high impedance loads
17. Dual JT-MB-C Microphone Combining Circuit - connect two microphones to one microphone input
18. JT-11SSP-6M Passive Stereo Matrix for M-S Mic Technique
19. MC-2 Microphone Combiner - product datasheet with circuit diagram in pdf format
20. Simple line mixer - mix two line level sources to one signal, includes separate volume controls for both signals, passive circuit
21. Simple two line output combiner - convert consumer equipment stereo signal to mono or combine audio signal from two different equipments to one input
22. Stereo to Mono Combiner for Balanced Systems
23. Interconnection of Balanced and Unbalanced Equipment - 4 page booklet in pdf format
24. JT-10KB-D & JT-DB-E Provide "J-Box" Consumer to Studio Interfaces - from -10dBV unbalanced to 150 ohm balanced microphone level (-45dBu) signal and from +4dBu balanced signal to -10dBV unbalanced signal
25. JT-10KB-D & JT-6110K-B "Pro" to "Consumer" Interfaces - from +4dBu balanced output to -10dbV consumer equipment input
26. Audio Transformer: The Ultimate Noise Killers - application note article on audio transformers
27. Grounding and Shielding - describes basic audio transformer uses like balanced in/out and signal splitters
28. Internal Modification to Mic Inputs of the Mackie 1604 Mixer Eliminates RFI Problems - adding transformer isolation increases common mode rejection and eliminates RF interference, pdf document
29. Jensen Transformers Application Schematics
30. JT-11P-1 as "Phase Splitter" with Symmetrical Outputs
31. JT-10KB-D Isolates and Converts Speaker Drive to Line Level
32. JT-11P-1 used as Unbalanced Polarity Inverter
33. JT-11-DM Converts Unbalanced Output to Balanced
34. JT-11SSP-6M Bi-directional Lo-Z Long Line Application - this circuit isolated and impedance matches under 100 ohm source to long cable line and that to over 10 kohm input
35. JT-6110K-B Isolates "70 Volt" Line and Converts to Line Level
36. JT-DB-E Converts Consumer Stereo Inputs to Mono Balanced Mic Output
37. JT-MB-C Isolates both Mic and Line Inputs of Inexpensive Mixer
38. JT-MB-C "Real" Mic Inputs & Phantom Power for Sony DAT
39. JT-MB-C Mic Input Isolation for Mackie Mixers
40. JT-MB-D Converts 600 Ohm Unbalanced Mic to 150 Ohm Balanced Mic Line
41. Mixed feedback drive circuits for audio output- technical paper from Lundahl Transformers in pdf
42. 2-wire Remot Microph- uses special amplifier module from Opa
43. Amplified Ear - Useful to listen in faint sounds 1.5V Battery operation, includes electret microphone preamplifier which runs from 1.5V DC and can directly drive 32 Ohms impedance mini-earphones
44. Audio preamplifier circuits - three transistor microphone preamplifiers
45. A Vacuum Tube Microphone Preamp / Direc- from January 1997 EQ Column, includes phantom power
46. Balanced mic/line amp with TUBES - uses two 12AU7 tubes in a class-A cathode-driven input stage, followed by a class-AB1 cathode follower output stage, 6db gain, requires 90VDC and 12VDC
47. Balanced Mic Preamp - based on SSM2017 and has option for 48V phantom power
48. Balanced Microphone Preamp Project - simple preamplifier with phantom power
49. Condenser microphone hookup
50. DIY Speaker Testing Microphone Preamp
51. Dual Phantom Power Microphone- information and full schematic of a kit available from PAiA Electronics, take also look at the circuit
52. ECM Mic Preamplifier - low noise electret microphone preamplifier
53. Electric Crayons, Anyone? (A Vacuum Tube Microphone Preamp / Direct Box Project) - published in January97 EQ Column
54. IC mic preamp uses Jensen Twin-Servo topology
55. Intercom preamp - a convenient way of making an intercom is to use a loudspeaker as a microphone
56. Jensen Transformers Application Schematics - includes many microphone preamplifier related circuits
57. JT-13K6-C in Simple One IC Stage Mic Preamp - 15KB PDF
58. Kondensaattorimikrofonin esivahvistin - simple preamplifier for electret microphone, text in Finnish
59. Low Noise Balanced Microphone Preamp - very low noise, close to the theoretical minimum, high hum rejection and variable gain with a single rotary pot, similar to that used in many professional grade mixing desks
60. Low Noise Microphone Preamplifier
61. Mic-Pre Pan Pot Circuit
62. Microphone preamp - very simple two transistor circuit
63. Microphone Preamplifier by Jason M. Neal - suitable for speaker measurements
64. Modern Microphone Preamplifiers - A paper originally published in R-E-P Magazine, contains general information but does not contain circuit diagrams
65. Mu Stage Tube Mic Pre - microphone preamp based on a Jensen transformer and an Alan Kimmel designed "Mu-mode" gain stage
66. PAiA Tube Mic Preamp
67. Simple microphone preamplifier - amplificator simplu cu un tranzistor
68. Simple Transistor Audio Preamplifier - for electret microphone
69. Standard Microphone Preamplifier Input Circuitry - pdf file
70. Taos Amp Solid State Mic Preamp - simple transformerless microphone preamp, includes circuit board design
71. Vintage Neve Class A Circuit Information - Neve BA283AV Class A Preamaplifier Circuit
72. Boundary-layer dish microphone - ideas for a directional microphone assembly
73. Build a pair of binaural microphones
74. Build These Noise-Canceling Headphones - plus Binaural Microphone Headset, Audio Probe, and Parabolic Microphone
75. Computer Microphone - adapting electret microphone to soundcards with dynamic microphone inputs
76. DAT-Heads Digest #195 - many electret microphone wiring tips
77. DIY microphone for Sony MD R35 minidisc recorder - simple electret microphone
78. Electret MIC Apps - an electret MIC is the best value for money omnidirectional microphone you can buy for 90% of microphone application
79. Electret microphone connection - how to connect electret microphone
80. Electret microphone powering circuits
81. Homemade Binaural Mics
82. Inductive pickup - simple device for detecting audio-frequency electromagnetic signals, such as those emanating from a loudspeaker, or it's cable
83. Interfacing Microphones to Computer Sound Cards
84. JT-MB-D Passive Stereo Matrix for M-S Mic Technique
85. JT-MB-C Used to "Phantom" Power the Realistic PZM Mic
86. Making a rugged, connectorized microphone from a Panasonic microphone capsule
87. Radio Shack Pressure Zone Microphone (PZM) Modifications
88. Schematics of old tube mics
89. Speaker Microphone - allows you to use a cheap loudspeaker as a poor microphone
90. Taos Amp Stereo Bar - how to build special microphone holder for two microphones for near coincident stereo techniques
91. Telefunken (Neumann) U47 FET Retrofit - inlocuirea tuburilor cu tranzistoare FET
92. Couch Drop: Momentary on/off floor switch for microphones - data sheet with circuit diagram in pdf format, includes no-pop mute function
93. Phantom Power Supply Circuit - Here is a simple phantom power supply that uses a voltage doubler circuit so that a commonly available low voltage transformer (such as a Radio Shack 273-1366A) can be used to produce 48 to 52 Volts DC.
94. Hi-Fi Preamplifier
95. Phono Preamp - realizat cu tuburi
96. Phono Preamps For All - a collection of phono preamps and equalisation circuits, one of which is sure to meet your requirements
97. Preamps (phono RIAA) - 10 RIAA preamplifier schematics
98. QSX Mark II - The extreme phono (RIAA) amplifier
99. The ampage schematic collection - guitar and bass preamplifiers
100. A Better Volume Control - how to create a log pot that is better than the "real" thing
101. Add-On Stereo Channel Selector - electronic switcher for 4 stereo sound channels
102. CMOS IC makes low-cost digital potentiometer
103. Digitally control gain over a ±40-dB range - digitally control an amplifier's gain over a ±40-dB range gain resolution of 1.25 dB
104. Digital stereo potentiometer - in pdf format, text in Finnish
105. Digital Volume Control - based on DS1669 Digital Pot IC
106. Dual-Channel Digital Volume Control - this circuit could be used for re-placing your manual volume control in a stereo amplifier
107. Elektroninrn potentiometri - Potentiometru electronic cu push butoane, text in Finnish
108. Inexpensive relays form digital potentiometer - build a digitally controllable isolated potentiometer which can tolerate voltages up to 60V dc
109. Linear potentiometer implements logarithmic gain control - trimmer potentiometers are ubiquitous components and are available in a variety of packages, resolutions, and temperature stabilities but none of these potentiometers implements anything but the usual linear function of resistance vs shaft position as useful in many audio applications
110. Single stage gives logarithmic gain steps - by placing a variable component in the positive feedback loop of an op amp, you can vary the gain of the stage logarithmically with respect to a linear resistance or conductance
111. Tack a log taper onto a digital potentiometer - idea to convert linear digital potentiometer to a logarithmic digital potentiometer
112. Variable-gain stage uses voltage-output DAC
113. Voltage controlled amplifier - three different circuits
114. Voltage Controlled Audio Panner - variable gain amplifier circuit
115. Voltage-controlled stereo signal attenuator
116. 10 band audio equalizer - ascii drawing of simple circuit
117. Adjustable 60Hz Filter - to filter out any HUM that may be picked up by a noisy power supply or long wire connection
118. "A" Weighting Filter For Audio Measurements - design based on an old Ampex circuit
119. 3 KHz low pass filter plus audio amplifier - circuit uses a switched capacitor filter IC MF6-50 from National Semiconductor to filter signals with frequencies higher than the 3KHz needed for voice audio, pdf file
120. Basic Active Filter Circuit Blocks
121. Five Band Mono Graphic Equaliser - basic mono unit originally designed for improving the apparent sound quality when dubbing video
122. A Basic Introduction to Filters - application note on active, passive and switched capacitor filters, document in PDF format
123. Active Filters - Butterworth, Bessel and Linkwitz filter example circuits and equations
124. Audio Graphic Equaliser - simple 7 band equalizer
125. Basic gyrator design - basic building block of graphic EQ
126. Designing A Pocket Equalizer For Headphone Listening
127. Filters - examples of very many different filter types, good page for filter design information
128. Have Ya Ever Been Too High?? - filter that is intended to take the harshness off some sources of sound that have an upward response tilt, go to the end of page to find this circuit
129. applicati
130. Multiple Feedback Bandpass Filter
131. Musical Instrument (Expandable) Graphic Equaliser - standard equalizer plus bonus distortion unit
132. Notch Filter
133. Parametric And Sub-Woofer Equaliser - simple parametric equalizer circuit
134. Tone Control Circuit - classic Baxendall tone control circuit
135. Tone Control - based on TDA1524A tone control IC
136. Tone controls wi- check also
137. 24db/octave Linkwitz-Riley
138. 3-way 4th Order Active Crossovers for Car Audio
139. A 2nd Order All-Pass 80Hz Active Crossover
140. Hifi 100/1 aktiivi alipäästösuodin - modified version of Hifi 100/1, only lowpass filter section, text in Finnish
141. High Pass Filter - second order active low-pass filter with equation to calculate component values for different frequencies
142. Low Pass Filter - second orrder active low-pass filter with equation to calculate component values for different frequencies
143. Renkus-Heinz Schematics - includes some crossover and speaker controller schematics
144. Schematics Of Various Tubed Crossovers
145. Subwoofer filter - 12 dB/octave low pass filter for subwoofer, includes subsonic filter
146. Audio Amp Output Power Limiter
147. Audio level control device - compressor circuit based on LED and photodiode
148. Compressor using photoresistor - very basic circuit based on LED, LDR and OPAMP
149. Designing A Limiter For Headpho- review of diode-based limiter design, HeadWize Desig
150. Dynamic Range Processor - this stereo unit allows the dynamic range of a signal to be increased (expansion) or decreased (compression) by a variable amount up to 3:1, based on the SSM2120 dynamic range processor IC
151. Fast Audio Peak Limiter
152. Q&D Compressor - A complete guitar compressor/limiter design based on SSM2165
153. Q&D Compressor 2 - based on SSM2166
154. Stereo Broadcast Limiter Circuit for the Ramsey FM10a/FM2- also available in Postscript
155. Stereo Compressor
156. Teletronix LA-2A Leveling Amplifier - a vacuum tube-type leveling amplifier (more commonly known today as a compressor) for professional audio recording and broadcasting use originally made during the mid to late 1960s
157. Ultra Simple Bass Guitar Compressor - based on LDR connected to signal cable and lamp connected to speaker output
158. Analog Music Zone Guitar Effects Schematics - guitar effects, compressors
159. Digital Echo Unit - mono unit for producing special effects for amateur dramatics
160. Distortion Effect (for guitars) - three distortion circuit ideas
161. Distortion effect for guitars
162. Effect Rack Unit - contains very many guitar effect unit circuit diagrams
163. Effectronics Schematics - audio processing and effect circuits
164. Guitar Amplifiers Overdrive & Distortion Effect Circuits
165. Guitar Effects Boxes - guitar effect schematics and articles

1. Guitar Effec Circuits - Wah, Fuzz and sustain circuits
2. Guitar Fuzz Effect - very compact circuit
3. Guitar Reverb Pedal - circuit for a guitar spring reverb pedal, it has dry, wet, and drive controls for a wide variety of sounds
4. Guitar-related Circuits - effect circuit collection
5. Guitar Vibrato Unit
6. Ha- contains effect information, schematics and constructi
7. Humbucking & Noise-Reducing Electronics for guitars
8. Improving a guitar - information on rewiring an electric guitar
9. MOS Doubler - clean sounding version of an octave up, uses CMOS logic
10. Musical Instrument (Expandable) Graphic Equaliser - standard equalizer plus bonus distortion unit
11. Not Just Another Headphone Amp - battery-powered musician's practice and monitoring amplifier for guitar
12. Spring Reverb Unit For Guitar
13. Stage Center Reverb Unit - simple spring reverb unit
14. The GEO-Fex collection of vintage and new-design effects and musical related DIY
15. The Guitar Effects Oriented Web Page - FAQs and circuit diagrams
16. Vox AC30 Guitar Amplifier Simulator
17. CD Buddy - Karioke device
18. How to filter out voice in music - very simple method
19. The Truth About Vocal Eliminators - sometimes a vocal can be removed almost completely, but just as often the results are disappointing, just information without circuit diagrams
20. Build A Stereo Synthesizer - different frequency ranges appear at the two outputs, depending on the setting of the controls and create a stereo effect
21. Burwen audio processor documentation - dynamic noise filter and eliminator circuit diagrams
22. Digital Potentiome- information about digitally-controlled solid-state electronic potentiometers from Dallas Semico
23. Dynamic Noise Reduction Circuit - reducator dinamic de zgomot
24. Mixed feedback drive circuits for audio output- technical paper from Lundahl Transformers in pdf
25. Square wave to sine wave converter circuit
26. Stereo Width Controllers - vary the width of the "sound stage" when listening to stereo recordings
27. Synthfool - many musical instrument and effect circuit diagrams
28. Simple Surround Sound Decoder - three simple surround decoder circuit ideas
29. Surround Sound Decoder MK1 - designed to extract the rear channel from Dolby-encoded film soundtracks, very simple design
30. Surround Sound Decoder Mk2 - fully featured surround decoder
31. The PTI SD-PL1 surround sound decoder - This circuit takes a stereo audio input from any true stereo source and outputs 4- or 5- speaker surround sound. The effect sounds ridiculously similar to Dolby ProLogic.
32. Andrew's S/PDIF Stuff - S/PDIF converter circuits
33. CD-ROM to MD - get toslink signal from your CD-ROM drive
34. Cheap TOSLINK Transmitter
35. Coax Digital Out to MD - Convert the coax signals to TTL signals for Toslink module
36. Coax to TTL conv- check also circuit board
37. Optical output for Creative Infra CD-ROM - little circuit to connect your MD or DAT to your CD-ROM drive with standard optical S/PDIF cable, based on TOTX173
38. SPDIF Circuits - input and output interfacing circuits
39. S/P-DIF I/O Using the Epoch SoundPro HT-1869V+ Card - circuits for S/PDIF to TTL interface and TTL to S/PDIF coax
40. SPDIF RCA to (Optical + RCA) Adapter
41. S/PDIF to TOSLINK
42. TTL to Toslink converter circuit
43. A SCMS k- should work with all DAT decks that have a Sony CXD2601 signal processor, published in September 1992 in "Stereoplay", also available at ftp://ftp.cs.ruu.nl/pub/MIDI/DOC/pbsc
44. Copybit deleter - sets the copybit in digital audio signals to enable copying of digital recordings
45. Audio Crafters Guild Articles & Essays - DAC building articles
46. JT-DAC No. 3
47. SDS Labs DAC Page
48. CS8420 is asynchronous sample rate converter c- includes example circuits, pdf file, check also evaluation board
49. CDplayer's Project - information to make and upgrade a CDPlayer at home
50. CrystalClear AC'97 AMR Audio Modem Riser card reference design
51. Digital Delay Unit For Surround Sound
52. Passive circuit monitors AES data - you can display the data waveform on an oscilloscope easily with this circuit
53. -30dBm to +30dBm Audi- circuit with balanced input and adjustable gain to drive needle type VU meter, uses special amplifier module from Opa
54. Audio LED VU meter - built around discrete components
55. Audio Millivoltmeter
56. Audio Output Level Meter - This unit is designed for monitoring the audio output level across a loudspeaker when carrying out alignment of radios.
57. LED Audio VU Meter - logarithmic scale with 3 dB steps, based in LM3915 IC
58. LM3916N bar graph driver - datasheet in pdf format, drives a 10 LED bar graph with VU proportions (3dB/step)
59. Medidor de Señal de Audio (VUmetro) - Vumeter circuit, schematic and PCB. Text in spanish.
60. Peak Reading Audio Level Meter - indicates peak audio response on an analogue meter, similar to a tape recorder recording level meter
61. Peak Reading Level Meter Using Indicator Tubes
62. Sound Level Meter - one chip replacement for the standard analog meters, based on LM3915 audio level IC
63. Stereo VU Meter - A simple, low cost stereo VU meter that uses two LM3915 dot/bar display driver ICs to drive 2 rows of 10 LEDs moving bar display, pdf file
64. Three-Level Audio Power Indicator - Battery-operated 3 LED display that connect it to loudspeaker output
65. Understanding Peak-Reading Meters - includes one example circuit diagram
66. VU And PPM Audio Metering - circuits using analugue needle meters
67. VU Meter - 5 led VU meter, in pdf format, includes circuit board, text in Finnish
68. VU Meter Amplifier
69. VU Stereo Meter - will indicate the volume level of the audio going to your speakers by lighting up LEDs, based on LM3915 IC
70. Room Noise Detector - One LED monitors three levels: 50, 70 & 85 dB
71. A-weighting filter
72. A Weighting Filter For Audio Measurements
73. A-B Switch Box For Amplifier Comparisons
74. Build a Microphone Polarity Tester
75. Building the L-R Test Set - helps you to set up left/right channel balance on audio broadcasting ystems
76. Linkwitz Cosine Burst Generator - part of speaker measurement set described in the construction article
77. Microphone Circuit Test Oscillator - tone generator for testing XLR microphone lines
78. The ESP SIM (Sound Impairment Monitor) - a method of determining just how much your amplifier modifies the original signal
79. Distortion Analyser - filters needed in distortion measutements
80. Distortion measurement circuit
81. Power Amplifier Clipping Indicator
82. Pre-Distortion Techniques: Build a Tape Linearizer and a Distortion Analyzer
83. Self Oscillating Amplifier for Distortion Testing - allows the home constructor to make quite accurate measurements, without having to spend a lot of money on a low distortion oscillator
84. DIY Speaker Testing Microphone Preamp
85. Measuring Input and Output Impedance - input or output impedance of any two terminal network or electronic equipment can be determined by measuring the small signal ac currents and voltages
86. Simplified Measurement of Output Impedance - suitable for measuring audio circuits
87. Spectrum Analyzer and Equalizer Designs - for audio frequencies, article first appeared in the February 1982 issue of Recording-engineer/producer magazine
88. Burwen TNE7000 Transient Noise Eliminator - Schematics and Lineup Instructions
89. Burwen DNF1201A Dynamic Noise Filter - Schematics and Lineup Instructions
90. Laser Link Communicator - audio transmission up to few hundred meters
91. A Better Volume Control - use linear potentiometer and one tran resistor to make almost logarithmic response curve
92. Amplifier Thermal Protection and Shutdown Circuit
93. Amplifier Timer - Turns-off your amplifier when idle for 15 minutes, fed by amplifier tape-output
94. Ask the Applicat- a collection of articles from its "Analog Dialog" newsletter in pdf format from Analogue Devices, useful info for people designing aDC and DAC
95. Audio Auto Shutoff - purpose of this circuit is to automatically turn off any device plugged into its power outlets after a certain period of time of silence
96. Class A Amplifier Design
97. Determining Output Transformer Impedance - When replacing the audio output transformer on a radio, the replacement should match the impedance of the original as close as possible
98. DIY class A amplifier chassis & massive heatsink
99. Dual +/- 15 volt power supply - suitabe for powering many opamp circuits
100. George Krilov audio schematics page - page is about transistor audio power amplifiers, contains articles about power amplifiers shematics, design, construction and SPICE simulation, page is partially in English and partially in Russian
101. Guitar Effects FAQ
102. Jensen Transformers Application Schematics - many practical circuit ideas using audio transformers
103. JT-115K-E90 "Sync" Conversion for Magna-Tech 69C Repro Amplifier - sync track tape head preamplifier
104. Load Sensing Automatic Switch - apply power to the entire audio system by turning on one item, simple circuit
105. Loudspeaker Protection and Muting - information and circuits
106. Low Noise Audio Input Stage - idea for audio input stage for magnetic pickup or microphone using three transistors from Zetex, design note in pdf format
107. Main principles of amplifier wiring - how to wire operational amplifier circuits
108. Mixed feedback drive circuits dor audio output transformers - using feedback eliminates transformer distortion and primary resistance
109. Mosfet Power Amplifiers - A discussion of the benefits of the lateral Mosfet output devices used in todays High Power audio amplifiers
110. NE555 drives a speakes: Pulse Width Modulation Amplifier
111. Philips SAA1099 Sound Generator
112. Proper Grounding Inside Equipment Avoids Ground Noise Coupling (aka"Pin 1 Problems") - 15KB PD
113. Pushing the Limits of Audio Power Amplifiers
114. Removing the "DC Thump" from Audio Circuits
115. Signal Detecting Auto Power-On Unit - switches on relay when detects sound input
116. Sheldon's Audio Designs - audio DACs and tube amplifiers
117. Simplest Ever Amplifier Bridging - a design for a simple add-on bridging adapter for stereo power amplifiers
118. Simulation Electronique SPICE - some hifi circuits and simulation of them using SPICE, text in French
119. Soft-Start Circuit For Power Amps - redusces the current spike large transformers take when switched on
120. Subtleties count in wide-dynamic-range analog interfaces - transporting high-dynamic-range analog signals from one piece of equipment to another is not a trivial task, this article gives some help to it
121. The ALTMANN "SPLIF" Amplifier Topology - something about how to get some of the feedback out of our HIFI amplifiers
122. Thermo-Fan To Keep Your Amp Cool - fan controller which controls fan based on temperature
123. Variable Amplifier Impedance - idea of being able to vary the output impedance of a power amplifier
124. Andrea Ciuffoli Document Page
125. "Anti-RIAA" Equalizer for Line to Mag Phono Converter
126. Infrared Cordless Headphone -Proiect de cost redus pentru a reproduce sonorul prin infrarosii
127. JT-11P-1 used as Unbalanced Polarity Inverter - transformator pasiv bazat pe inversor audio de curent
128. JT-11P-1 Unbalanced Automotive or Consumer Application
129. Model Train Diesel & Horn Sound Module
130. Cirrus Logic Consumer & Professional Audio ICs - linkuri spre produse si documentatie
131. Cirrus Logic CS4334/35/36/37/38/39: 8-Pin, 24-Bit, 96 kHz Stereo D/A Converters
132. TDA1387T; Stereo Continuous Calibration DAC (CC-DAC)
133. CS3310: Stereo Digital V- from Cirrus Logic, verifica si IC datasheet
134. DS1267 Dual Digital Potentiometer - form Dallas Semicondictor
135. Analog record and playback IC's - raport studentesc
136. CS8401A/2A: Digital Audio Transmitt