High Quality Intercom circuit
This is an intercom circuit which use LM380 as the audio amplifier and 2 transistors as the microphone pre amplifier. The sound quality will be good enough with...
Symmetric Output for USB Audio DAC
This simple adapter circuit is specially intended for use with the USB Audio DAC published in this website elsewhere. With an easily implemented modification, i...
Modular Headphone Amplifier
Those wanting private listening to their music program should add this Headphone Amplifier to the Modular Preamplifier chain. The circuit was kept as simple as ...
Schematics Stereo Parabolic Microphone
The mini condenser microphone converts sounds into an electrical signal. Resistor R1 provides bias for the condensor microphone`s internal amplifier transistor....
Electric Guitar Preamplifier
Here is the circuit diagram of a guitar preamplifier that would accept any standard guitar pickup. It is also versatile in that it has two signal outputs. A typ...
Video-Out Coupling
If you want to connect a video signal to several destinations, you need a distribution amplifier to match the 75-ohm video cable. A distribution amplifier termi...
Ultra-Simple Microphone Preamplifier
This little project came about as a result of a design job for a client. One of the items needed was a mic preamp, and the project didn`t warrant a design such ...
Two Channel Audio Mixer
It is often convenient to be able to fade in or out or mix at any wanted level the inputs from two audio sources. The circuit in Figure 37 is suitable for this ...
Tone Controls
Operation is from a 12v or similar supply, and R1 can be changed if necessary for higher voltages. In this and similar circuits there is considerable latitude i...
Modular Phono Preamplifier
Any electronics amateur still in possess of a collection of vinyl recordings and aiming at a high quality reproduction should build this preamp and add it to th...
Crystal Microphone Preamplifier
Figure 36 is the circuit of a preamplifier with high impedance input and an output circuit allowing coupling to a main amplifier. It will be found extremely use...
Crowbar Speaker Protection
Crowbar circuits are so-called because their operation is the equivalent of dropping a crowbar (large steel digging implement) across the terminals. It is only ...
Simple MD Catridge Preamplifier
Phonographs are gradually becoming a rarity. Most of them have had to yield to more advanced systems, such as CD players and recorders or (portable) MiniDisc pl...
RIAA Phono Preamplifier
Since modern sound systems usually lack inputs for record players, separate MD preampliers are becoming increasingly popular. They are needed not only by peop...
FM Wireless Microphone
Here is a very simple, inexpensive and interesting project which provides lot of fun to a home experimenter or hobbyist. This simple transmitter can transmit sp...
5.3W Amplifier With Surround System
The AN7147 Dual 5. 3-watt Audio Power Amplifier from Panasonic is listed as a replacement type` so hopefully will be around for some time to come. Together with...
Schematics USB Sound Card with PCM2702 PCB
Make a sound card is no more a complex issue. If you use great IC PCM2702 from BURR BROWN / Texas Instruments you can create a fully functional USB sound card. ...
audio peak detector
This audio peak detector allows a pair of stereo channels to be monitored on a single LED. Identical circuitry is used in the left and right channels. Use is ma...
HiFi preamplifier for computer soundcard circuit
This circuit can be used for inductive pick-up elements and dynamic microphones Most soundcards have a line` input and one for an electret (condenser) microphon...
playback amplifier for cassette
For some time now, there have been a number of tape cassette decks available at low prices from mail order businesses and electronics retailers. Such decks do n...