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Can you help me with my Velleman K8066 Amplifier Chip Answered

Im new to the audio hobby but i had put together a velleman k8066 amplifier chip everything is soldered properly but the sound coming from my speaker is sounding distorted. I have a 9volt battery hooked up to it as the power supply. In the book its says power supply between 6 and 15vdc. One last question is there any way to build like a tube or something so that my speaker will sound louder. Also it says speakers 4-8 can be connected

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rickharrisBest Answer (author)2012-01-15

Push the power supply voltage up if you can also as Steve says try to make sure it can supply enough current at least 1/2 amp. Higher voltage will reduce the current requirement.

Generally distortion is cause by over driving so that the amplifier clips the audio into a square wave. Lots of rock guitarists desire this effect but for reasonable audio it isn't really what you want.

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tramont (author)rickharris2012-01-15

So basically just a higher supply voltage? And also how would i turn that portable.

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steveastrouk (author)tramont2012-01-15

Use small batteries, even AAA will work better than a 9V rectangular.

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tramont (author)steveastrouk2012-01-15

should i just use what 2 of them

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steveastrouk (author)tramont2012-01-15

4 will give you your six volt minimum supply. See what happens with a battery that can supply your load current. Add more, and see if that stops the distortion.

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tramont (author)steveastrouk2012-01-15

Just to ask: If this is a 3watt amp can I hook 2 2ohm 2watt speakers? Do i need to match my speaker rating with my amp rating?

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steveastrouk (author)tramont2012-01-15

Yes, ideally, for maximum power tranfer, don't put too low a speaker rating, or you might blow the speaker.

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tramont (author)steveastrouk2012-01-15

also how can i make it to where i can listen to it at high volumes without distortion currently im using 2 2ohm 2watt speakers

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tramont (author)steveastrouk2012-01-15

thank you so very much it worked. There is a little distortion but not as worse as before. Thx so much

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Thermionic (author)2012-01-14

Do you have any kind of pre amp in the circuit? I would bet this is an active versus passive issue. If you have a schematic, post a link to it so we know what were dealing with. Also, please be more specific. Signal source, speaker age and origin, skill level at electronics. All these things will help us answer you.

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tramont (author)Thermionic2012-01-15

http://www.velleman.eu/downloads/0/illustrated/illustrated_assembly_manual_k8066.pdf thats the link with the schematics. My skill level is beginner. Also what is a signal source. Also I dont know the speaker age or origin when i was younger i kept tearing old radios and stuff up for the speakers.

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steveastrouk (author)Thermionic2012-01-15

I can't really see his phone output needing a pre-amp, though I may be wrong. Looking at the speaker and the amp though......

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steveastrouk (author)2012-01-15

Try a decent power supply and a speaker without a crushed dome in the centre

The Amp is 3W, so I reckon you need a power supply that can crank out 500mA or so.

An old wall-wart supply off a router or something would do.

Steve

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steveastrouk (author)2012-01-14

That speaker doesn't look very healthy. That might be an issue.

Do you have a volume control ? Does it distort even when quiet ? If it does, ttry it with a battery that can provide more current

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tramont (author)steveastrouk2012-01-14

no i dont have a volume control but when i turn the volume down on my phone it doesnt sound that bad

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