Posted on Feb 5, 2014

MP3 players are all the rage these days. The smaller ones in memory-stick format are particularly easy to take with you; your very own personal sound system` on the move! It`s when you want others to share your taste in music that you ¬nd these players to have a lack of power. You can get round this problem with the help of the MP3 booster, a sm

Click here to download the full size of the above Circuit.

all amplifier that can be used to connect your MP3 player directly to your Hi-Fi. When you next invite your friends to a party you can ask them to bring their personal music` as well as the usual drinks! But ¬rst we have to build this booster! The small battery-powered players have an output signal that is more than suf ¬cient to drive a set of 32 Ohm headphones. You`ll often ¬nd that with an output of 1mW the sound pressure level (SPL) produced can reach up to 90 dB. This would be suf ¬cient to cause permanent damage to your hearing after only one hour! The maximum output voltage will then be around 200mV. This, however, is insuf ¬cient to fully drive a power amplifier. For this you`ll need an extra circuit that boosts the output voltage. Power amps usually require 1 V for maximum output, hence the signal has to be ampli ¬ed by a factor of ¬ve. We will also have to bear in mind that quieter recordings may need to be ampli ¬ed even more. We`ve used a simple method here to select the gain, which avoids the use of potentiometers. After all, the MP3 player already has its own volume control. We decided to have two gain settings on the booster, one of three times and the other ten times. Ampli ¬ers IC1A and IC1B (for the right and left channels) are housed in a single package, a TS922IN. The output signal of the MP3 player is fed via a stereo cable and socket K1 to the inputs of the amplifiers. The gain depends on the...

Leave Comment

characters left:

New Circuits



Popular Circuits

Linear analog coupler
high impedance input JFET/BJT buffer circuit
Wireless Switch
ac phase control triacs
Super bright LED night light
EUA2123 20-W Stereo Class-D Audio Power Amplifier
Stepper Motor Controller
Arduino Vocal Effects Box
code switching EPROM circuit
ISO103 ripple reduction circuit diagram
Use SR9F26C ordinary language learning machine tape recorder and circuit diagram