[hendern88]

I've just received one of these from Hong Kong ( sorry ).

It works when I connect to the phone-in sockets but all I get is loads of static and a faint sound of music when connecting via a digital coaxial or toslink.

I'm using various DVDs at the moment as transports and using PCM and 48mhz.

Two questions :-

I assume that using the Phone- in gives no bennefit of using the DAC or does it as no digital input.

As the Digital inputs just give a garbled mishmash of sound is it safe to assume that my new Hong Kong derived DAC is bust and needs to go back !!!

cheers
Neil.

 

[Puffin]

I think you will find that there is a Digital IN socket (one) and two analogue OUT sockets (to amplifier). You may have connected it wrongly.

 

[pmkap]

Neil,

What you're describing sounds like the same problem I had when I recieved my Zhaolu. The way I dealt with it was to hook it up with the cover off and with the dac powered and fed a signal. gently press down on the back row of pins connecting the dac boad, this brought the low volume (with clicks) back to a functioning dac. It might well be a intermittent connection on the board, not associated with the dac (all the power as well as the 'lock' leds were lit), but the resulting small flexure of the whole pc board might have been sufficient to reconnect whatever intermittent connection. This frustratingly reappears intermittently, and the probable fix is to track down that faulty connection and fix or simply reflow all the solder joints from the underside of the pc board. Prior to taking a soldering iron to your unit, you should contact whoever you bought it from for advice (which is what I should be doing)
FWIW,
Paul

 

[chesebert]

Quote:

Originally Posted by hendern88 I've just received one of these from Hong Kong ( sorry ). It works when I connect to the phone-in sockets but all I get is loads of static and a faint sound of music when connecting via a digital coaxial or toslink. I'm using various DVDs at the moment as transports and using PCM and 48mhz. Two questions :- I assume that using the Phone- in gives no bennefit of using the DAC or does it as no digital input. As the Digital inputs just give a garbled mishmash of sound is it safe to assume that my new Hong Kong derived DAC is bust and needs to go back !!! cheers Neil.

48Mhz ..that's your problem

you need to input either in 96Khz or 44Khz. I don't think the board accept 48Khz..

 

[bizkid]

Nope, 48khz works fine here with both DAC boards.

 

[hendern88]

pmkap, your bang on ....sadly !!!

so much for quality control from our far eastern chums....

Well were do I go from here....is the problem the main pcb or the DAC...is this a possible diy fix or a shop.....sending it back to Hong Kong is a no no..

going well at the moment though....some 1hr without crackling so maybe good for some time....I'll just be carefull not to bang it !!!

cheers
Neil.

 

[Ori]

Quote:

Originally Posted by hendern88 so much for quality control from our far eastern chums.... Well were do I go from here....is the problem the main pcb or the DAC...is this a possible diy fix or a shop.....sending it back to Hong Kong is a no no..

There are two possible scenarios.
One is a loose or dirty contact in the sockets of the plug-in board. Remove the screw and unplug and plug that small board - or use a contact cleaner.
The second possibility is a loose/cold solder joint.

Flip the main board over and inspect the plug-in socket's connections and all the RCA jack connections. A visual inspection may not reveal a cold solder joint, so you may have to just go "brute force" and heat up all these joints with a small soldering iron.
The last possibility is to send it back to HK, which is a real pain...

 

[pmkap]

Neil,

While its unfortuneate that we're both on the recieving end of 'teething pains', I consider this to an example of the law of unintended consequences, or, stuff happens. A freind here in NYC recieved a stock Zhaolu, and its been running perfectly. My own Zhaolu had the upgraded caps, and when Eddie reinserted the pc board, he left out the screws securing the board on the front perimeter, and only screwed it down with a single screw in the boards center. Some thing that at the time didn't bother me at all. I've no doubt that the DAC worked perfectly when it left Eddie's and that it had been subjected to that 3 day burn-in when it left HK. But it might be possible that Eddie unknowingly in leaving out those screws, facillitated the boards vibrating on its inter-continental delivery flight, and the result is a stress fracture on the pc board, resulting in our common problem.
As far as what to do, I'll e-mail Eddie and provide a link to this thread. Perhaps he has had this happen with others and has recieved back a faulty board and can point us to the likely place requiring a solder reflow. If not, with Eddie's permission, I'll borrow a magnifying visor (I've terrible eyesight) and try to track down the problem. I've no problem with taking a multimeter and soldering iron to the DAC myself, but would like to avoid any potential finger pointing conflicts.

Its unfortunate that we're the winners of the 'schit happens' contest, but I don't ascribe this to any lack of qc on Eddie's part. We simply learn from our mistakes. Nor am I confidant that the lack of affixing screws are the cause. Does your unit lack the full compliment of fixing screws?

Aside from our problems, I really think the Zhaolu a wonderful, charming DAC. Its even better with minimal opamp upgrades.

At this point, I think it best to pursue this via email with Eddie. Hopefully, the problem was caused by the combination of missing fixing screws and transportation induced vibrations. If so, reinsertion of all screws prior to transport might well fix the problem and avoid it for others in the future.

Regards,
Paul

 

[pmkap]

Ori,

Sadly, I don't think the problem is #1 as I've cleaned and reinserted the dac board and opamps. As the intermittant problem appears on both channels, even when all the proper LEDs are lit, I'd guess the problem is an intermittant connection on the opamp voltage rails from the regulator. I'm awaiting a response from Eddie and plan to borrow a magnifying visor..... This might solve my problem, but Neil doesn't appear to be a solder slinger.

Regards,
Paul

 

[hendern88]

Hi Paul,

Thanks again for your help...mine's still going fine.

Crossed wires a little ...I bought mine via Buyoyo.com....I'm sure from all the posts on this board Eddie does a cracking job.

It is a fab sounding DAC and I'm delighted its working at the mo thanks to you..if it goes off again, yeh I'll try to track the issue down myself as well.

cheers
Neil.

 

[Ori]

Quote:

Originally Posted by pmkap As the intermittant problem appears on both channels, even when all the proper LEDs are lit, I'd guess the problem is an intermittant connection on the opamp voltage rails from the regulator.

See if the LED on the plug-in board is lit up, which indicates incoming data. If not, then most likely the unit will go to mute and you'll know the issue is at the input circuit. Otherwise I'd say you're right about the supply. The opamps receive only the +-16V from the discrete supply (with the heatsink). Check that the level are adjusted to +-16V and not anything higher. That might cause a thermal problem with the opamps (just speculating). I've seen one unit with much higher voltages. Someone forgot to check?!

 

[rincewind]

The faults in a product made by one manufacturer (especially when it's modded after initial manufacture) has nothing to do with the quality control from a whole company.

 

[hendern88]

My DAC came from Zhaolu without being modded...QC issue..possibly...not an issue really for Zhaolu as I'm sure its a very small % but you'd think all units would be tested before leaving the factory leaving only transport to damage and would have to be quite a jolt to break a board connection ( ? )...

Its gone again ....so guess its solder iron time.....good while it worked though.

cheers
Neil.

 

[seticruncher101]

i also have the popping issue between tracks (and sometimes in the middle of the track) this is really frustrating and scary sometimes. i'm using Squeezebox 2 (coax) to D2 (AD module) direct to amp.

i found this issue with SB2 http://forums.slimdevices.com/showthread.php?t=24070

it's really hard to tell if the problem is with SB2 or D2, i installed the beta slimserver and it fixed the popping issue.

i then used SB2(coax)-->D2-->receiver and everything's fine, sound quality is not as good as direct to amp but there's no popping

then i switched back to SB2(coax)-->D2-->amp and the popping came back,
i configured slimserver to stream to wav, still popping.... switched to optical and the popping went away.

when i first received the D2 i used my computer as a source using Foobar and coax out of creative x-fi with no issues.

i'll try to experiment more on different setup to isolate what's causing this stupid popping... the headphone amp is disconnected.

can this popping damage my speakers?

i really want to do the DC blocking caps mod but i'm afraid of the popping issue, better to fix that one first before moving to more mods. my unit have 2x2604 and 1xDY2000, blackgates, metal film resistors, and other caps upgrade.

i also noticed that the transformer is loose, the two clips screwed to the case that holds the transformer is not holding the transformer in place. is this normal or should i bend the clips to tighten the transformer? also, when i have the cover on w/ no screws i can hear buzzing from the unit, haven't tried putting the screws back 'cause i'm running my D2 w/ no cover. it's preety nice to look at with all the red LEDs.

my impression right now with Z2 is "IT"S GOOD WHEN IT WORKS, BUT IT'S REALLY FRUSTRATING TO DEAL WITH THIS POPPING ISSUE"

 

[Disiskurt]

I think there's been a few people having that problem pairing the Zhaolu with the Squeezebox.