[honmashinsei]

Quote:

All the best mate and I hope you enjoy the unit!

Thanks

I ordered mine on Friday.

 

[Squa7ch]

I have a problem...I bought a new mouse (RAZER Lachesis) seems now my uDAC-2 doesn't work properly, assuming it's due to the report rate of the mouse (125/500/1000Hz)...if I unplug the mouse it works fine but soon as I plug in the mouse the uDAC-2 goes silent...so if there' no way around this I'll basically have to send the mouse back because it's useless to me if my uDAC-2 doesn't work...

 

[jasonl]

Please don't speculate

.  All uDAC-2 are manufactured exactly the same.  We sold more than 1000 uDAC-2 and I would attribute the noise that you hear to 1) human ears, 2) earphones compatibility or 3) system noise.  The computer is never built to effectively isolate digital noise.
Many EU homes have no proper AC ground and that could attribute to higher noise (similar to Japan, this is a nasty problem for high-end audio). With a more sensitive uDAC-2, the problem might be exposed. Perhaps you can try to power up the uDAC-2 by connecting the USB type-A connector to a USB charger to power up the uDAC-2. Try it on different AC circuit.
Or just try to connect the laptop SMPS to a different AC circuit (or reverse the AC plug - for EU customers).  If you can borrow a AC noise filter, give it a try.
 
If my recollection is correct, bcwang has super sensitive ears so if he can't hear it, few people can.
 
Jason
 
Quote:

Trying to look at the data, it's difficult to decipher the problem.  Many don't hear the tone, and at the 1-2.5khz frequency level that's been reported, it's well within the audible range for anyone.  Those that do hear it can hear it with replacement units as well.  I wonder if there could be big batches that are affected, so all from the same retailer would be from that batch.  It would be more interesting if someone could find a unit with the problem and one without the problem (which doesn't seem to have occurred yet) then we would know it is a hardware problem somewhere. 
 
I do notice a lot of the people reporting they can hear it seem to be outside the US.  They probably do get completely different manufacturing batches.  I also wonder if noise on the usb line could be affecting it based on the power grid operating frequency.  The reports vary so much on this, it's baffling so far.
 
I myself don't hear any tone whatsoever with any of my headphones from highly sensitive IEMs to high impedance full size.  It's been on 3 computers with 4 different usb cables and the behavior is the same.  From reports the tone should be loud enough to be obvious.

 

[jasonl]

 
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Bummer for Nuforce 

 
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I ordered my uDac-2 directly from NuForce via Amazon and I have no noise at all. I am using it in the same room as cellphones, wireles networks and other wireless products so I do not think it has anything to do with wireless interference. 

 
With so many uDACs sold and still being sold every day (we are upping the production to 3000 units per batch and these are mass production, so they are very consistent) and a few people are going to have incompatibility issues.  If it doesn't work for you, we offer full refund. 

 

[IsoOctane]

Quote:

With so many uDACs sold and still being sold every day (we are upping the production to 3000 units per batch and these are mass production, so they are very consistent) and a few people are going to have incompatibility issues.  If it doesn't work for you, we offer full refund. 

Well, there is certainly "some" sample variation with regards to the noise because like I mentioned, in the second unit of mine the tone was of considerably lower frequency than in the first. And I confirmed it was the unit itself by keeping the USB port and the cable the same. The serial numbers of the two units only differed by 12 or so, by the way.
 
In addition, it was confirmed by many that the noise remained even when running the uDac off a laptop isolated from the power grid.

 

[tinseljim]

To help take at least one cat away from the pigeons....if you want to get rid of any noise/hiss try this :
 
1) Attach an 1/8th inch to RCA adaptor to the RCA-outs at the back.
2) add a female to female adaptor to the 1/8th inch plug.
3) Plug your headphones into the female-female adaptor.
 
job done. no hiss at all!
 
a few caveats with this method:
1) i don't have/hear any tone with mine so this may or may not work for that.
2) the main difference in sonic signature is that you lose a bit of sparkle and soundstage - though it would be interesting to hear what other people find. 
3) you will also gain a bit of volume so be careful. 
3) i'm using cheap cabling/interconnects at the moment so this may contribute to the different sound signature. 
 

 

[thuantran]

You might wanna use usbview http://www.ftdichip.com/Support/Utilities.htm to try and isolate your mouse and the udac-2 to be on two isolated physical hubs. Please report back if this fixes your problem. I'm curious.
 
You might try to use the mouse with vanilla windows mouse driver, too. To see if your guess was correct. Lastly try them on another computer.
 
Quote:

I have a problem...I bought a new mouse (RAZER Lachesis) seems now my uDAC-2 doesn't work properly, assuming it's due to the report rate of the mouse (125/500/1000Hz)...if I unplug the mouse it works fine but soon as I plug in the mouse the uDAC-2 goes silent...so if there' no way around this I'll basically have to send the mouse back because it's useless to me if my uDAC-2 doesn't work...

 

[replytoken]

Quote:

Please don't speculate

.  All uDAC-2 are manufactured exactly the same.  We sold more than 1000 uDAC-2 and I would attribute the noise that you hear to 1) human ears, 2) earphones compatibility or 3) system noise.  The computer is never built to effectively isolate digital noise.
Many EU homes have no proper AC ground and that could attribute to higher noise (similar to Japan, this is a nasty problem for high-end audio). With a more sensitive uDAC-2, the problem might be exposed. Perhaps you can try to power up the uDAC-2 by connecting the USB type-A connector to a USB charger to power up the uDAC-2. Try it on different AC circuit.
Or just try to connect the laptop SMPS to a different AC circuit (or reverse the AC plug - for EU customers).  If you can borrow a AC noise filter, give it a try.
 
If my recollection is correct, bcwang has super sensitive ears so if he can't hear it, few people can.
 
Jason
 

Jason,
 
Thank you for weighing in at this point in the thread.  And more importantly, thank you for [size=10pt]acknowledging [/size]that the noise some of us are hearing may be related to earphone compatibility.  The uDAC-2 is a great product that can produce some incredible sound.  Its just that this situation its very frustrating for those of us who are experiencing these noises, for whatever reason.  Even if nothing can be done about this situation, I am guessing that those of us who are experiencing these noises were hoping for some validation/confirmation from NuForce.  I will not speak for others, but I can understand, and am often times willing to accept, trade-offs in a product's design.  Over the years I have learned to live with a very high nosie floor from tube preamplifiers feeding my solid state amplifier.  It would be great if there were virtually no noise floor, but that's not the case.  So, given the sound they produce at their price point, I have learned to use attenuators and live with them as they are.  As their are many variables in play here, and at present it seems like just a small number of us are hearing noise (relative to the total number of untis produced), I can understand that you are not able to say much more other than to remind people that you have a very liberal return policy.  I do, however, hope that if you are able to personaly experience the noise that we are hearing, and are able to identify a solution, that you will remember us.  I believe that reputations and customer loyalty are built upon doing the right thing.  Offering a trial period and liberal return poicy at the time of sale is certainly the right thing in my book.  Remembering me, and my needs, after the sale is "going the extra mile", and something that generates a large amount of goodwill.
 
--Ken
 

 

[mr-teatime]

Well articulated Ken! 
 
 
... I wonder if there is somebody in London with a UDAC2 — I'd be really keen to compare devices.
Importing it from the US was expensive and took ages, I don't want to do anything before I'm sure that there are really differences (because as I said before, with my fullsize cans it sounds superb).
 
Any Londoners?
 
 

 

[lazpete]

So, wich phones does work? All my phones are apperantly incompatible. As explained in the audiocircle thread http://www.audiocircle.com/index.php?PHPSESSID=1mqr6o817j11gen9ld3phc527jm9n945&topic=85916.msg845824#msg845824 ive tried even with a stand alone battery, the tone is still there, on two separete units. And the talk about all units are made the same, what is that? Do nuforce meen that all units pass the QC? If thats so, the QC must be out of this world, or just not existing. I want a UDAC2 without the tone,.

 

[Spirit2]

Is imbalance a normal problem with the udac 2? If I have the volumeknob at 9 o'clock or lower, I will get higher sound to the left. I guess this is common, but I just wanted to check. 

 

[replytoken]

I do not want to say that misery loves company, but I felt a little better seeing a totally idependent thread on AudioCircle, if only it proves that we at Head-Fi are not subject to "group think".  As we are fortunate to have choices with respect to our purchases, I am probably ging to consider the "tone" a quirk and keep the unit since it works quite well in other capacities, and I know of no other portable USB DAC in this price range that has RCA outs.  I am hoping that NuForce will devote a bit more time to this issue, with the hope that the cause can be identified, and the issue resolved.  As NuForce has offered an upgrade path for original uDAC owners, I am hopeful that uDAC-2 owners will be able to easily upgrade to a "uDAC-3" at a reasonable cost.
 
--Ken

 

[replytoken]

Quote:

Is imbalance a normal problem with the udac 2? If I have the volumeknob at 9 o'clock or lower, I will get higher sound to the left. I guess this is common, but I just wanted to check. 

IIRC, the uDAC-2 is supposed to have better volume control and balance at low levels than the original uDAC.
 
--Ken
 

 

[Spankypoo]

Another customer here to whine about the whine.
 
I hear it on everything from Sennheiser MX500s to JH13s. I've tried it through my USB hub, without it, plugged into a USB charger or a laptop running only on battery. Whine every time.
 
And everything in the configurations I've tried is identical to the setup of the uDAC 1 it replaced (which didn't produce any such noise).
 
Sorry, but there exists a design flaw and/or a production variance. To assume anything else is to bury one's head in the sand.
 
Edit: And it's loud enough that I can hear it over music.

 

[kite7]

Nothing but silence here with my silver uDAC-2 with my Westone 2 IEM. I have it plugged in to my desktop right now with a very good power supply, I will try to give it a go on a laptop or another computer sometime and report back.