Wolfson WM8740 DIR9001 PCM2706 DIY DAC

[dtses]

Originally Posted by alatar66

The 7808 is a regulator that produces a lot of noise, the better an LM317 for example.

Dario's shunt on LM317 would be even better I hope as I'm building several now for Wolfson's and DIR9001 analogue parts.

Did you notice any difference with TeddyPardo?

[alatar66]

Originally Posted by dtses

Dario's shunt on LM317 would be even better I hope as I'm building several now for Wolfson's and DIR9001 analogue parts.

Did you notice any difference with TeddyPardo?

Although I have not tried, because I haven't finished the DAC.
But the sound of the Wolfson should be cleaner.

[dtses]

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

[noSmoking]

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

[nvduybom]

Originally Posted by alatar66

Anyone know more about the update to wm8741? I have not quite clear. On the website of the 8740/8741/8742 Wolfson are pin-compatible. But then I found this:

Wolfson WM8741 Stereo Audio DAC

a

In this kit board, the power supply for WM8740 analogue and digital is 5V , so I think if you want to upgrade 8741, you must regular 3.3V for digital

[nvduybom]

Originally Posted by alatar66

Anyone know more about the update to wm8741? I have not quite clear. On the website of the 8740/8741/8742 Wolfson are pin-compatible. But then I found this:

Wolfson WM8741 Stereo Audio DAC


[

In this kit board, the power supply for WM8740 analogue and digital is 5V , so I think if you want to upgrade WM8741, you must regular 3.3V for digital

[dtses]

besides the new version of this chip and new improved numbers, is there any point swapping the original one in this DAC? Has anybody done any comparison?

[nvduybom]

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) .

[noSmoking]

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

[nvduybom]

Hi noSmoking,

Thanks. I checked the regular 7812 and 7808 is ok (no hot). I will try connect direct from WM8740 to output transformer LL1544A.

I care the WM8741 dac kit of twistedpearaudio, it look good.

Best regards

Van Duy