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Why is my iPod amplifier circuit fuzzy? Answered

I used an LM386 audio amp with its usual circuitry to amplify signals from an iPod headphone jack, but the sound quality is terrible. I have tried powering the circuit with a nine volt battery, and with a wall wart, and, although sound quality was better with the battery, it was still pretty bad, and not very loud. I have tried different LM386 chips, and a speaker that I know is of decent quality, and the sound is still bad. I have also used a filtering capacitor in series with the decent speaker, and the quality was okay, but the sound was very faint. Sometimes with the wall wart I got a weird buzzing noise, and with either the battery or the wall wart I often get unpredictable gain from the amp and bad sound. My speakers are around 2-21/2 inches in diameter, and around 10 Ohms, and the decent speaker is of unknown dimensions and around 9 Ohms. I also tried one of Kipkay's homemade speakers, and, no offense Kipkay, but it all went badly after that, probably because my homemade speaker was only 4 Ohms, when it should have been 8 ( The speaker is not Kipkay's idea, he credits it to Jose Pino, from Make Magazine, vol. 12). I'm also using generic 24 guage wire, not speaker wire, could that be the problem? Please help! Thanks! P.S. I tried to make one of those big LED's sync to the music, but ended up burning it out with the wall wart, will the smoke hurt me? Thanks!

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frollardBest Answer (author)2009-03-31

to quote the will-it-blend guy, "dont breathe this!" anyhoo What volume is the ipod outputting at? you want the ipod to output at 'signal' levels, not 'headphone' levels, otherwise you will be amping an amped signal and it will sound awful. Can you use the ipod dock connector for the line out?

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jeff-o (author)frollard2009-04-01

Yep, try this first - turn the iPod volume to maximum. If that doesn't do it, either the circuit you found was bad, or you did something wrong. Look for short circuits, open circuits, and backward electrolytic caps.

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frollard (author)jeff-o2009-04-04

exactly opposite - you want the volume capped at about 25%. 100% volume would be strong enough to power small speakers. Amping such a signal would have a clipped, gross sounding sound.

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jeff-o (author)frollard2009-04-04

Any of the iPod amps I've ever had work much better with the iPod volume at max.

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pixeldrift (author)jeff-o2009-12-20

Actually, on an iPod line out is only about a tenth of a volt higher than the headphone jack. Try this site for more info on the levels:

http://beavishifi.com/articles/headphonejack/

Though the line out through the dock connector is not affected by the volume control and is a straight signal.

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bolandm56 (author)2011-03-09


For the speaker try using 32 or 34 gauge wire, it will make the speaker sound a lot better

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roneldatuin (author)2010-05-05

make sure the speakers are not in series..also the led.

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11010010110 (author)2009-03-31

find online another 386 circuit and try building it from scratch. maybe you have a damage in some resistor or capacitor or soldering which can be hard to spot i prefer TDA2002 for amplifiers

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