WEILIANG DAC5 - WM8741 & Tenor TE7022

I just got a DAC7 and have been listening to it for a few days. I'm very happy with it. I've been comparing it to my "TDA1541A Reference DAC" (with tube output) and the DAC in my Denon AVR-2106 (which as far as I know uses AD1837 chips).

The AVR-2106 is a great sounding receiver with good DACs, but the DAC7 is very noticeably superior to the Denon DACs. I need to do some tweaking on the TDA1541A DAC because it doesn't sound quite as good as the Denon, and is blown away by the DAC7. Considering that some people have spent more on a custom transformer for the "reference DAC" than it costs for a working DAC7, I would say this little guy is a good deal.

I think this is a great buy and I would be interested to see how close it gets to Cambridge Audio's DACmagic. I would be surprised if it sounded much better than this.
 
dac7

I have finished the Dac7 from Weiliang. Wow! The dac seems surpassed the Cambridge. I have AD825's in it. Very nice. I tried some different opamps, not one is as good as this is. Have somebody used other opamps?
If you are looking for a dac, buy it (no connection with it).
Regards
batalok
 
Hi Weiliang,

Is it possible from you to launch PCBs with the chips (Te7072 and WM8741) soldered only? Or naked PCBs with the chips to solder separately? This would be very liked and helpful for and from DIYers who would like to build their own output stages/power supplies.

I personally would like to try the chip direct out, it has big capacitance drive (1nF).
 
I have finished the Dac7 from Weiliang. Wow! The dac seems surpassed the Cambridge. I have AD825's in it. Very nice. I tried some different opamps, not one is as good as this is. Have somebody used other opamps?
If you are looking for a dac, buy it (no connection with it).
Regards
batalok


Hello batalok,
Thanks for your kind share! Happy that you like the DAC7!
AD825 is good, I use 2 pcs OPA627 mono to dual, also is nice!:)

If someone want to have a try, assembled board is your choice, assembled WM8741 DAC7
 
can anyone confirm that all the standard spdif sample rates work with this wm8804/5 style board?

its my understanding that this spdif rx chip will not 'sort out' 176/192k properly in hardware mode. software, yes, with some magic, but not hw mode.

so, can anyone confirm that this does really work at 44/48/88/96/176/192 rates?
 
interesting. have you tried 192k as you switch to it from all the various other rates? I'm curious if it 'landed' on 192k in all cases or if it ever gets confused.

my testing of the 8804 series says that in hw mode, it just can't be counted on for 176 or 192. they spec sheet says it needs to 'know' and this is only in sw mode.

btw, kevin, are you talking about this board or just the wolfson spdif rx chip?
 
I finished soldering my dac 5 v1.9, and of course it doesn't work...
the voltage swings wildly on LM7808 both input and output. don't know where to start debugging it, could it be the smd voltage regulators soldered incorrectly?
does anybody has a picture with the unsoldered pcb, the region with smd regulators?
 
I got my set of kits (2 kits and 1 assembled) yesterday for the similar DAC7.

I noticed that quite a few of the voltage regulators were used, removed from old equip and 'recycled'. usually, I do not have confidence in parts from china ebay kits and I prefer to replace most of the key parts (filter caps being the first thing I throw away and replace).

you may have gotton a bad part. but after you assemble it, its kind of late to order all new parts from known distributors (mouser, etc).

if you are seeing input to the 7808 vary, it could be possible the 7808 and things following it are loading you down so much that the input can't supply enough current. ie, a fault downstream?
 
This is what I have - hope it helps. It's V1.3
 

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here's an assembled version of the DAC7 and the recommended r-core trafo.

my friend bought the assembled one and I bought a pair of the kits, still yet to be built. I have a feeling that I'll need the working model to help me fully be sure about every kit part ;)

the assembled version is up and running and it appears to make sound. again, a working model is always handy if my kit version goes south on first build.

my plan is to try controlling the 2 wolfson dac chips via software, so I have to 'edit' the board a bit to convert it from hardware mode to software mode. TBD.
 

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found the problem (or at least one of the), pin 11 and 12 on 8805 were soldered together, missed that when I inspected the board after soldering.
but during testing, I managed to short circuit the board and 12V went through the smd regulators. one of them blew up (always use protective goggles), God knows if that's the only damage.
 
pics of 2 of the dac7 kits (one assembled and one built by me).

I have my crossover modified (dcx-2496) to send out 2 spdif signals and those are what comes into this set of dacs via the usual yellow 75ohm cables.

yes, the mounting is temporary ;) the cardboard box base came from a laptop accessory pack, lol. it was sturdy enough to hold these parts together so that I can take my time to find a more proper box for them.

the sound is pretty good. they run VERY HOT, though (the analog rails, mostly). the shunt regulator system throws off a lot of heat and I wish those heatsinks were bigger, at least. or that another regulation scheme was chosen.

on my board, I used different electrolytics and my single 1000 was larger than their series of 3 of the supplied blue ones. so I used all my own parts where I thought things might benefit or save weight. 2 regulators were not needed as I don't need or want the usb board and I don't need the toslink input.

the white color actually helps you (the builder) locate shorts or soldering faults. I like the white color for this reason, its useful, not just different ;)
 

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