Building a chip amp

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DaveF
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Re: Building a chip amp

Post by DaveF »

Great work Fran. Very impressive.

I've got an old Myryad MA120 power amp that I havent used in many years. No idea if it works anymore. You're welcome to take it and rip it apart. Should have a good power supply and it has a lovely case.
"I may skip. I may even warp a little.... But I will never, ever crash. I am your friend for life. " -Vinyl.
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Fran
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Re: Building a chip amp

Post by Fran »

Thanks Dave - yes indeed I would be interested.

It might be interesting some time to try the chip amp with the kharmas too - although its not a class D amp like Kharma's own....


Fran
Do or do not, there is no try
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DaveF
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Re: Building a chip amp

Post by DaveF »

Fran wrote:Thanks Dave - yes indeed I would be interested.

It might be interesting some time to try the chip amp with the kharmas too - although its not a class D amp like Kharma's own....


Fran
Sure thing. Let me know whenever it suits you once you got the amp built.
"I may skip. I may even warp a little.... But I will never, ever crash. I am your friend for life. " -Vinyl.
Michell Gyrodec SE, Hana ML cart, Parasound JC3 Jr, Stax LR-700, Stax SRM-006ts Energiser, Quad Artera Play+ CDP
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Rocker
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Re: Building a chip amp

Post by Rocker »

Fair play to you FRAN. Lovely work, can't wait to hear it.
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cybot
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Re: Building a chip amp

Post by cybot »

Another year, another project :) Well done Fran.....
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Fran
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Re: Building a chip amp

Post by Fran »

Final pics....


Not much has changed in the internals from the last pics, but I used a stepped DACT type attenuator instead of the Alps blue velvet shown in the earlier pics. I added bigger capacitors in the power supply as well, and lastly, I changed the resistors that set the overall gain of the amp to LDRs. These last ones are worth a mention. They are light dependant resistors - in other words, resistors whose resistance changes depending on the amount of light to fall on them. The particular ones I have used (and the ones that are used by all in audio around the world) are from a company called Silonex, and are actually a package of the resistor, plus an LED. So the idea is that the amount of power you put through the LED creates a certain amount of brightness, and therefore a certain resistance. If you can do that accurately, then the resistance is dead on accurate. Anyway, it turns out that these resistors seem to have a kind of magical sound quality. Example: I had used audiophile kiwame resistors in this position. Well regarded ones.... but when I added in the LDRs I got a better, more defined, cleaner presentation.

Anyway, I think she's kinda finished now. I might go back sometime and do another one with 2 chips per channel paralleled which is meant to give a higher power output, but its not something I feel the need to go for right away.

Excuse the fingerprints on the fascia: I thought I had them all off!

Fran
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Ivor
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Re: Building a chip amp

Post by Ivor »

It's lovely. Looking forward to hearing it sometime.
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cybot
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Re: Building a chip amp

Post by cybot »

Beautiful......
fergus
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Re: Building a chip amp

Post by fergus »

Excellent work as usual Fran!
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DaveF
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Re: Building a chip amp

Post by DaveF »

very impressive Fran. Lovely neat finish too.
"I may skip. I may even warp a little.... But I will never, ever crash. I am your friend for life. " -Vinyl.
Michell Gyrodec SE, Hana ML cart, Parasound JC3 Jr, Stax LR-700, Stax SRM-006ts Energiser, Quad Artera Play+ CDP
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