Wolfson WM8740 DIR9001 PCM2706 DIY DAC

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Just finished mine. It surprisingly plays on first plug in, USB is no hassle to set up and sounds well. I did a quick comparison to iPod Nano (which is BTW better sounding than iPod Touch) and I have to say that playing through the USB is much better than playing the same file by iPod.
Like I wrote earlier, almost all parts seem to be fake, so I picked up all new stabilizers, new caps and resistors. I plan on changing OPamps as well.
 

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few pics of mine.
 

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hi marchel,

parts are from the kit except rectifiers. I'm not sure whether caps and other parts are genuine, however my Cerafines looks ok to me. Moreover, I have found them on ebay (though could be fake too) and seems to me to be some old series, not fake ones. As to the other parts - FCs, I do not see any point to counterfeit them, they are not so expensive, resistors as well... However I'm not an expert and do not have big experience in DIY like dozens of projects...

Perhaps I would change diodes to some high speed Schottky, all 47uf caps to Silmics and opams to some good metal LME49710HA.

Anyway, I'm not sure does it worth it as haven't made any decent tests against my heavily moded Philips CD350 or some other CDs :) but it's good to know that the DAC is better than iPod at least.
 
as a reference I took this picture from some other seller. Moreover, checked this part with a tester according to the lines on it, got no impedance unlike on all other res, so I was thinking it's some kind of new Chinese cap. Correct me if I'm wrong.
 

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cheers!

finally found and ordered chassis for the dac. It's not the best you can find, though bearing in mind dac's price I suggest it's ok. Moreover front plate could be replaced with some thick black glass for instance. Inside is enough place for pcb and three transformers.

Also ordered new genuine FCs and Silmics to replace all caps and be 100% sure of decent parts used there.

One question makes me feel uncertain. Could anyone pls explain me what is the purpose of quartz here (near the usb) and could it be replace with external clock as further upgrade?! As far as I know in CD players quartz/ clock determines the speed of a disc or some other stuff too?!
 
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I think that cap is a EMC filter cap to reduce hf noise on the output cable.

Please don't take it the wrong way but I still don't understand. What kind of purpose is it suppose to serve? If that should be a low pass filter the cut off frequency is 15.9MHz (I hope I calculated it right). From my point of view it's not supposed to be there at all. But I might be wrong. regards
 
It is intended to reduce the radiation of the clock and it's harmonics onto the cable which would form a good antenna to radiate the noise.
This is very common practice in electronic equipment.
A clock typically has significant energy upto it's fith harmonic so a 12MHz clock will have energy upto at least 60MHz.
Regards Andrew
 
I'm on a way to change all psu caps to FCs and 10uf, 47uf to genuine Elnas, at least to be 100% sure that I'm getting maximum from the parts. Swapped diodes to fast Schottky ones.

Also finishing adjusting the case that turned up to be very good for price paid 30 USD (incl. European delivery)
 
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