Review: ZERO 24 BIT/192KHz DAC/Headphone Amp/Pre-Amp

[shampoosuicide]

Hi guys, I just got my DV332, and am having some problems with the Zero's RCA connector.

It seems that it's a bit loose, and the RCA cables won't fit properly. So there's no sound unless I hold the RCA cables up. I imagine this could be worked around with some blutac, but should I send it for repair?

[Ivion]

Greetings everyone, it sure was one heck of a job reading through this entire thread... yet it made the waiting for my very own Zero DAC/amp much more bearable. I ordered my Zero from Lawrence when I was still only somewhere around page 200 of this humongous thread and only read about his failing quality control when it was too late...

My Zero arrived yesterday morning and from the get-go I heard there was something amiss with the sound, every time I turned the volume control on the Zero I could hear distortion, but only in the left channel. Figuring it probably had something to do with headamp section of the unit I first checked if my ALPS pot (which Lawrence had installed) was properly grounded, which it was. After that I decided to check if there was no distortion if I used the RCA-outs connected to my integrated amp... the distortion did not pass. This was somewhat odd, because now the distortion (still only in the left channel) appeared when I turned the volume control on my integrated amp.

Undaunted I unseated one of the LT1364 which were used in the headamp section and put it in the DAC section instead of the HDAM. After listening for a short while through my integrated amp I could no longer detect any distortion when I changed the volume (because I've got no spare opamps I naturally couldn't use the headamp section as well). When I was about to reinstall the HDAM I noticed that some of the wires of the extension wire weren't soldered quite properly, so I set out to resolder those few wires which didn't seem to have been done properly.

Now I tried again, with the repaired (or so I hoped) wire... but still the distortion was apparent. Getting kind of desperate I then tried to free the HDAM from the encasing, to which it was stuck with some kind of dual-sided adhesive tape and after some work with a knife and a flat screwdriver I succeeded in doing so. Now I could plug the HDAM directly into the socket without the need of the extension cable, and what did you know? No more distortion in the left channel while changing the volume! Be it with the volume control on the Zero itself or with the one on my integrated amp.

Thinking I was out of the woods I set out to spend some quality listening time with this DAC/amp, but sadly I was mistaken... Because after some time listening I noticed that there sometimes were slightly audible 'pops', which sounded somewhat akin to the sound you hear when the needle of an element passed a bit of dust on a vinyl record or, I would guess, to the sound of a small electrical (static?) discharge. Strangely enough these still only occurred in the left channel.
And ultimately it is this that I want to pose you all a few questions about.

Of course, the general question would be: what is causing this? Could it be that in my heroic attempts to free the HDAM from the case might have damaged it? Could it have been damaged because some of the extension wires weren't connecting properly to the module? Or could it be something entirely different, like the grounding of the HDAM? Or maybe a miscellaneous problem unrelated to the HDAM?

Any help at all would be much appreciated and I'm already planning to order one or two new modules straight from GD-audio itself including a better extension wire, but would like to postpone such things if I can get the sound coming from the Zero working properly.

PS: I appreciate you reading that large post... if indeed ye did not scroll past it!

[djchaz]

Random question, which would theoretically sound better:

-the Zero dac connected to a laptop via the Xitel USB converter

or

-the Zero dac connected to a laptop via an inserted an X-fi soundcard with an optical in/out.

Thanks!

[nauxolo]

Is it normal for the left channel of my headphones connected to the headphone amp to have static when I turn up the potentiometer? There's lots of static...

[Henmyr]

Originally Posted by nauxolo

Is it normal for the left channel of my headphones connected to the headphone amp to have static when I turn up the potentiometer? There's lots of static...

My Zero is like that.

[cuoreboy]

this my zero mod

[sandchak]

Originally Posted by cuoreboy

this my zero mod

very nice indeed.. I wonder how you fit the HDAM and still able to close the top lid.. I use to hear it had to be placed somewhere else via extension cables to get the cover on..

[sandchak]

Take a closer look and I really like this, how did you manage to get the HP section off??.. I am really interested to know because I intend to use the Zeros only as a DAC ONLY..

[Currawong]

Originally Posted by Scottyyy

This thread is still going strong I see. Haven't posted in here in months.

Just a quick question guys. Has anyone used their Zero with Markl modded D2000s or D5000s? I'm thinking of trading my HD650s for a pair, but I don't plan on changing my Zero.

This thread is far too big to search through.

Yes, I have. They work fine. Because they are low impedance headphones you might get a small amount of hiss.

Originally Posted by shampoosuicide

Hi guys, I just got my DV332, and am having some problems with the Zero's RCA connector.

It seems that it's a bit loose, and the RCA cables won't fit properly. So there's no sound unless I hold the RCA cables up. I imagine this could be worked around with some blutac, but should I send it for repair?

Sounds like a solder joint between the RCA sockets and the board has broken.

Regarding static with HDAMs, yes, I've had it. When testing the Sun, if it was plugged into the DAC section, I'd get heaps of static as I adjusted the volume. I also had a hum in one channel with one of the Sun HDAMs I have here. I strongly suspect it has to do with the opamp socket and bad contact between the pins and the socket.

By the way, for everyone else who hasn't seen yet (as it's not in my sig atm):

Introduction to the Zero DAC and Headphone amplifier. - Head-Fi: Covering Headphones, Earphones and Portable Audio

[Seba]

My Zero is broken. Won't output any sound anymore but seems to get a "lock" on the signal. I've tested with various sources and various op-amps.

I just send Lawrence an email asking if he could send me new main board PCB.

Hope everything turns ok.

[BigTony]

Quick 'buring in question'.
When I get my new HDAMs, can I put them in the H/A section (along with HDAM Earth in DAC) and plug phones in to speed up burn in time? Or won't it power 3 HDAMs at the same time?
I don't use the H/A section much, mainly used a DAC for my DV 332.

Cheers

[Currawong]

It'll power 3 HDAMs at the same time with no problems in my testing.

[fault151]

Does anyone want to buy my Zero from me? It comes with opa 627's on a brown dog adaptor and upgraded op amps in the headphone section.

PM me for more details.

I have just made a buffalo dac and i already own an opus dac + beresford dac so one of them has to go.

[oofie810]

Anyone here have a spare HDAM that they would want to sell? I'd be interested in buying if you're not using it anymore.

[sandchak]

Originally Posted by oofie810

Anyone here have a spare HDAM that they would want to sell? I'd be interested in buying if you're not using it anymore.

theres one in ebay now :

Brand-New Audio-GD Dual-OPA HDAM Earth Opamp w/ Extras! - eBay (item 290275503113 end time Nov-22-08 06:46:52 PST)

and currently I am the highest bidder!!!