555 SIREN GENERATOR
A simple design from 2 555 timers - this is versatile and loud. - NEW
AUDIO AMPLIFIER: PRE-AMP
A low signal pre-amp using an op-amp from a single battery supply -
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AUDIO AMPLIFIER: BRIDGED 20W 12v
A common amplifier based around the TDA2005 IC.
AUDIO AMPLIFIER: 7W
A simple circuit based around LM383 - NOT TESTED
AUDIO AMPLIFIER: 14W
Single supply and split supply versions of the popular TDA2030 amplifier
AUDIO AMPLIFIER: 32W
Single supply and split supply versions of the popular TDA2050 amplifier
AUDIO AMPLIFIER: GUITAR FUZZ
A classic design based around an op-amp - NOT TESTED
BASS/TREBLE TONE CONTROL
A neat little circuit providing +/- 3dB bass and treble boost
BASS/TREBLE TONE CONTROL - OP AMP VERSION
Another bass and treble boost tone control giving better performance using a single op-amp
BASS BOOSTER
A simple active op-amp filter that will boost and cut bass signals - possibly as part of a sub-woofer
FILTER - ACTIVE LOW PASS
Active filter based on Sallen Key design. Ideal for tone controls, subwoofer drivers and demodulating
FILTER - ACTIVE HIGH PASS
Active filter Sallen Key design. Ideal for tone controls, tweeter/midrange drivers and demodulating
PARAMETRIC EQUALISER
Tailor your audio with this variable frequency cut/boost filter
RING MODULATOR
Useful for sound effects - simple in design, based on just 2 transformers and 4 diodes - NOT TESTED
SOUND ACTIVATED SWITCH
This was connected to a battery powered mobile which activated when a baby cried
THEREMIN- NEW
Asimple version of a more complex design - enables you to literally play tune by hand!!
TRIANGLE WAVE AUDIO ASTABLE
A useful replacement for a sine wave generator, has AC/DC output and square and triangle outputs
VCA - VOLTAGE CONTROLLED AMPLIFIER
Fantastic little circuit that can be configured as a VCA, modulator and multiplier.