Tone Balance Schematics

• Digital Volume Control
• Digital Volume Control with DS1669
• Bass-treble, Volume, balance and Loudness control
• 2nd Order Opamp Filters
• Low-Sensitivity, Lowpass Filter Design
• Low Pass Filter
• DC accurate low-pass filter
• Galaxy Noise Filter Schematic
• Subwoofer Low pass filter
• Audio stereo Panner
• Panner Waveform Generator
• Active SubWoofer
• Feedback Bandpass Filter
• Audio Tone Control
• Auto Loudness Control
• 60-Hz, High-Q notch filter
• Active Tone Control
• 12dB / Octave Linkwitz Riley Crossover
• Filter For Audio Measurements
• Bass -Treble Tone Control
• TDA1524 Stereo Tone Control
• Tone Control Schematic
• low pass filter subwoofer
• Equal-element filter improves passband performance
• Single Op-Amp Bandpass Filter
• Highpass filters use modified equal-element design
• Parametric And Sub-Woofer Equaliser
• Battery-Powered Stereo Balance Control Features Low Distortion
• Stereo Width Controllers
• Active Filters: High Pass
• 3KHz LOW PASS FILTER & AUDIO AMP
• Cascade bandpass filters for higher Q
• Bandpass Filter
• Band-pass filters
• Tone Control Circuit
• AUDIO AMP + 3KHz FILTER
• 3KHz LOW PASS FILTER PLUS AUDIO AMP
• Closing the loop deepens notches
• Tiny 1MHz Lowpass Filter Uses No Inductors
• LowPass Filter
• ELECTRIC FIELD DISTURBANCE MONITOR
• High Q Notch Filter
• Stereo Width Controller
• Active Sub-Woofer and Controller
• Hum filter
• 20 Hz audio bandpass filter
• Adjustable high-frequency notch filter
• Adjustable filter provides lowpass response
• Tone Control
• Bass-treble tone control circuit
• Lowpass filter uses only two values
• Audio Notch Meter
• LOW PASS ACTIVE FILTERS
• Schematic of Low-Pass Active Filter
• "Brick-wall" lowpass audio filter needs no tuning
• Active filter has wideband tuning range
• Lowpass filter has improved step response
• Multiple Feedback Bandpass Filter
• Bass-treble tone control circuit
• RC Notch Filter (Twin T)
• Guitar Tone Control
• DPPs program key parameters of bandpass filter
• Baxendall Tone Control

Equalizers Schematics

• Graphic Equalizer
• 10 Band Graphic Equalizer
• 3 Band Equalizer
• 6-Band Graphic Equalizer
• Stereo Equalizer and Balance
• Parametric and Graphic EQ's
• Spectrum Analyzer and Equalizer
• Subwoofer Equaliser
• 3 Band graphic equalizer
• Parametric SubWoofer Equaliser
• Reverse RIAA Equaliser
• Subwoofer Equaliser
• 10 Band Audio Equalizer
• RIAA Phono Equaliser
• 10 Band Audio Equalizer
• 5 band graphic equalizer using a single IC/chip
• Better Volume (and Balance) Controls
• Digital-Controlled Graphic Equalizer
• 5 Band Graphic Equalizer
• Parametric MID Frequence EQ
• 10 Band Graphic Equalizer
• Audio Graphic Equaliser
• A Pocket Equalizer For Headphone Listening
• 6-Band Graphic Equalizer
• 3 Band graphic equalizer
• (Expandable) Graphic Equaliser
• Ibanez Graphic Equalizer
• Electro Harmonix Graphic Equalizer
• 6-Band Equalizer
• Graphic Equaliser 527
• Graphic Equaliser 533
• Graphic Equaliser 545
• Graphic Equaliser 537
• 5 band graphic equalizer using a single IC/chip

Microphone Schematics

• 2Channel + Microphone Stereo Mixer
• Op-Amp Microphone Preamp
• Portable Microphone Preamplifier
• Dynamic Microphone Preamp
• Computer Microphone preamp
• Portable Microphone Preamplifier
• Computer Microphone Schematic
• Condenser Microphone amp
• Dynamic Microphone Preamplifier
• Dual microphones separate voice from noise
• Dynamic Microphone driver circuit
• Electret Condenser Mic Preamplifier
• dish microphone
• Balanced Microphone Preamp
• Bionic Ear
• Speaker Microphone Circuit
• Sony C-37A Condenser Microphone
• Portable Mic Preamplifier
• Audio Perimeter Monitor
• Microphone uses phantom power
• The Simplest FM Mic
• Microphone pre-amp
• Low impedance microphone amplifier
• Microphone Voice-Over Circuit
• Underwater microphone
• 24 Watt Audio Amplifier
• Speaker Microphone
• Mike Pads
• Balanced Microphone Preamp
• electret mike amp
• simple mic preamp
• 100 - 108 Mhz Wireless Microphone
• Line level to microphone input adapter
• Condenser mic audio pre-amplifier
• Microphone Clap Switch
• Electret Microphone Preamplifier
• Loudspeaker as a Microphone
• Simple microphone preamplifier
• Mic Phantom Supply
• Low Noise Microphone Preamp
• Interfacing Pro Microphones to Computer
• Low impedance microphone amp
• FM Wireless Mic
• Spy-Mic with FETs
• TTL Mic-spy
• Shortwave Mic
• Mic Circuit Test Oscillator
• Simple Microphone Mixer
• Microphone Polarity Tester
• MINIATURE FM SPY MIC
• POP free mic on/off circuit
• Simple microphone pream
• Mini Microphone preamplifier
• MIC SPLITTERS
• Powering microphones
• Dynamic to electret microphone circuit
• Preamplified Wireless Mic

Mixers Schematics

• 4 input Portable Mixer
• 1 Transistor Audio Mixer
• two line output combiner
• Headphone driving for soundcards
• 2 CD-ROM drives to one soundcard
• Isolator transformer for audio lines
• Stereo Audio signal Isolator
• Hi Fi mini mixer
• 3 input audio Mixer
• 4 lines Stereo Mixer
• Audio Line Driver
• 2 lines FET Audio Mixer
• Speaker signals to line inputs
• line mixer
• Audio Modular MIXER with 6 and up input Channel
• 6 Input Mixer
• Mini Mixer Project
• Simple Line Mixer and Patchbay
• Portable Mixer
• Elevon Mixer for Transmitters
• 6 Input Mixer
• Voice-Over Circuit
• Six-channel Mixer and Amplifier
• High Quality Audio Mixer
• FET Audio Mixer
• Microphone Mixer
• Stereo Mixer
• 3 Line Mixer
• Simple line mixer
• Voiceover Schematic
• Audio Mixer - Transistorized
• Stereo Mixer Schematic
• 3 Line Mixer
• 2 Line Mixer

Vacuum Tubes Schematics

• ZUPER POWER AMPLIFIER
• Vacuum Tube Preamp
• 15 Watt Valve Amp
• Tube Amplifier Schematic
• Class A Amp with 5687 dual triodes
• Phono tube Preamp
• Class A2 SV811-10 Stereo Amp
• Vacuum Tube Theremin Schematic
• 845 20W A1 class monotriode amplifier
• A class and push-pull
• Tube Headphone Amplifier
• 60 Watt Tube Power Amplifier
• 2x45 Watt Tube Amplifier
• Push - Pull 24 Watt A Class Amplifier
• Push-Pull Class A 2A3 Stereo Amp
• 15 Watt Tube Amplifier
• CLASSIC MINIMALIST AMPLIFIER
• Pushpull Amp
• Tube dual opamp
• The Emperor's New Amplifier
• 500KW Transmitter Schematic
• Transmitter FM 45W with valve
• 3 - 5 Watt Class-A Audio Amplifier
• Tube power amplifier 5W with EL84
• Headphone tube amplifier
• Tube - Mosfet Opamp
• Tube Line Preamplifier Project
• CAR TUBE PRE AMPLIFIER
• Stereo Tube Amplifier
• 600 VOLTS POWER SUPPLY FOR QRO
• Phono Preamp
• Three Tube PHONO (RIAA) Preamplifiers with ECC83
• HF BANDS QRP LINEAR AMPLIFIER
• 2 VALVE TRANSMITTER
• Single Valve Transmitter
• OBTAINING 250vDC & 6.3vAC FOR VALVES
• Stereo Tube Amplifier
• 2a3 Tube Amplifier
• Vox AC 50/4 Amplifier

Buzzer Schematics

• warbler siren
• Two-tones Siren with IC 4093
• Proximity Alarm
• Door Chime Schematic
• Siren Generator Schematic
• Doorbell for the Deaf
• Electronic Doorbell with Counter
• Frost Alarm
• warbling sound alarm
• Doorbell Chime
• door-chime repeater
• Over Voltage Beeper
• simple electronic buzzer
• Novel Buzzer
• Controller provides multiple alarm-driver formats
• Birdie Doorbell Ringer
• Cuckoo-song Generator
• DING-DONG BELL
• Two tone generation
• 555 Tone Generator
• Novel Buzzer
• Ultrasonic dog whistle with 555
• Siren
• Timed Beeper
• Whistle Responder
• You've got mail
• VERY LOUD BEEPER CIRCUIT
• MACHINE POWER LOSS BEEPER
• Pushbutton Activated Beeper
• POWER REMINDER BEEPER
• Piezoelectric Triggered Switch
• Piezoelectric Vibration Sensor Activates Switch
• BASEMENT DOORBELL BEEPER
• LOUD PIEZO ALARM BEEPER
• Check Engine Beeper
• Beeper
• Bells ring Generator
• simple electronic buzzer
• Siren Driver Circuits
• Audio Millivoltmeter
• Battery Low Voltage Beeper
• BASEMENT DOORBELL BEEPER
• Bull Horn Schematic

Musical Schematics

• Multi-Melody Generator with Instrumental Effect
• CD-ROM Drive as Digital-audio CD-Player
• Simple Electronic Metronome
• Surround Sound Decoder
• Vocal Zapper
• compressor Effects circuit
• Instrumental visual feedback
• Guitar Reverb
• Guitar Reverb Pedal
• Stereo Synthesizer
• Metronome with CA741
• Sound Effects Generator
• Sound Effects Generator 2
• Tone Generator with 555
• Precision Metronome/Pitch
• Panner Waveform Generator
• Guitar Reverb Effect
• CW Sidetone Generator
• Guitar Reverb II
• Phase Shifter circuit
• Analog Synthesizer Module
• Direct Injection Box for Recording & PA
• 8 Note Tune Player
• RHINO8 EL Sequencer
• Guitar Tremolo Unit
• Metronome Circuit
• Instrumental Graphic Equaliser
• Mini Metronome
• Melody generator for greeting cards
• MIDI Controller Footpedal
• Guitar "wah-wah" Effect
• Guitar tone Control
• Guitar Reverb Effect
• Mini-Synth Guitar Trigger
• Bass Guitar Compressor
• Wave Multiplier for music synthesizers
• Mobile MP3 Player PC
• MUSICAL BELL
• Spring Reverb Unit
• Musical touch bell
• Hot Springs Reverb
• Precision Metronome
• one transistor theremin
• Voltage Controlled Panner
• Guitar Vibrato circuit
• Audio Voltage divider
• Electronic metronome
• Fuzz-box circuit
• WAH & FUZZ Guitar circuits
• 60W Guitar Amplifier with tone control
• 100W/4 Ohm Guitar Amplifier
• Bass 10W audio Amplifier
• Electric Guitar Hookup
• Atmel 2323 Digital Guitar Tuner
• 300W Subwoofer Amplifier
• Guitar Reverb Pedal project
• Guitar Effect Bypass Circuit
• Serial MIDI Interface
• timer remembers your rhythm
• spring reverb plans
• MIDI Drum Machine
• Portable Guitar Amplifier
• Car PC MP3 Player
• Guitar Amplifier

Ultrasonic Schematics

• Ultrasonic Pest Repeller circuit
• All transistor microphone pre-amplifier
• Tone Generator with 555
• Ultrasonic dog whistle with 555
• Ultrasonic Pest Repeller
• Practical UltraSonic Radar
• UltraSonic Switch
• "Good old" parking sonar
• remote control and Intruder detector
• Ultrasonic Switch
• Electronical Cricket
• Almost Ultrasonic Motion Sensor
• UltraSonic Radar
• Almost Ultrasonic Motion Sensor
• Basic IR Detector/Emitter
• Ultrasonics: remote control and Intruder detector
• 40khz IR tester
• UltraSonic Radar
• Sampling peak detector has shutdown feature
• Ultrasonic Range Meter
• Devantech SRF04 Interface to BrainStem GP 1.0
• ULTRASONIC EXAMPLE
• Ultrasonic Range & Imager
• Ultrasonic Range Meter
• Ultrasonic range finder
• UltraSonic Radar
• ultrasonic switch

Intercom Schematics

• High Quality audio Intercom
• Doorphone Intercom schematic
• Full-duplex Intercom project
• Transistorised Intercom
• 2-Way Intercom
• 4-Way Intercom
• old phones as intercom circuit
• old phones as an intercom with ring tone
• Practical Intercom Circuit
• 2-Line Intercom Telephone Changeover Circuit
• The Link Telephone Intercom
• Party line intercom circuit
• Intercom preamp
• 10 channels Intercom circuit
• Headset type Intercom
• Two line intercom
• Doorphone Intercom
• Intercom
• IR headphone transmitter CD4046
• Infrared Head Phones