Wolfson WM8740 DIR9001 PCM2706 DIY DAC

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Finally, finished with the case and all in/out RCAs.
Added separate 3rd Salas +5v for WM8740's analogue part, removed smd 5v regs.
 

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Hi Dtses

Looks good ,I also swapped out the caps for oscons and all the regs,I have some fast switch diodes but haven't got around to replacing them yet ,I ordered (4)blank boards and got the newer ones with the pots near the output opamps,they adjust dc offset,mine went to zero and stayed there(grounded input) to adjust.
It sounds great compared to some other dacs I have used,so I'm Happy!
I would like to use the wm8741 for the digital aspects,volume control and also filters has anyone done this and is it worth the time ,I built the first version of heartwinters Dac and it sounds good I switch the filter with a 3 pos switch and was wondering if it's worth going futher?
Nice build and case!:):):):)
Cheers,
NS
 
I removed USB, 74HC157 chip and replaced all 47uf Elna capacitor with 33uf tantan, Opam with LF356H gold pin .The sound really improved.

I have idea use I2S signal of airport express connect direct to WM8741 and output with transformer LL1544A (600:600) .
 

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Hi nvduybom,
Looking good,I also replaced the regs on top side because I haven't seen ones so thin and also mine got too warm for me so I heat sinked them,Just a small flat aluminum heat sink fixed it,
I haven't changed out for a 8741 yet,I have another dac that has 8741 in it ,but it also has a good clock and seperate power supplies for anolog and digital,it also gives you some digital filters and other digital (software/hardwire) features,I hard wired it with a switch and It sounds good ,best dac I have built so far,as far as sound goes, it was one of heartwinters boards on diyaudio.
Have fun!
NS
 
cheers!

I have a strange hissing on the right channel, it could start after an hour or two or could be heard even after 5min once the DAC is turned on. It's quite loud and very disturbing, as to the the music it continues to play on the same volume. Then after a minute or even 3-5 it suddenly vanishes like it appeared. The DAC operates with open lid, should not be any overheating. All joins have been resoldered, pbc checked for any micro tin remains.

Once it happens all power supplies show same correct voltage as before, what else could be checked here and what theoretically could be the reason of such hissing/ cracking white noise?
 
Hi Singod87,
If you have the newer version with the pots to adjust DC on output,and your amp doesn't need a preamp, then you can jump it and see if it has enough gain,also as you know opamp's have different sounds ,if any DC on the output of the dac output, use a input cap or check your amp input and see if there's one there then you won't need to add that cap,
Post back your results ,What amp are you using,It sounds good with gainclones!
Happy Listening,
NS
 
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