REVIEW (in progress) - Nuforce HDP 24/96 USB-Optical 24/192 Coax DAC Preamp and Headphone Amp - Page 103

I'm playing a 24/88.2 right now just fine...  

The device itself won't downsample but if you use a player like Audirvana, Fidelia, etc.  They will downsample or upsample depending on your preference settings.

NuForce claims that through USB, 88.2kHz is not supported.  I don't know if it downsamples to 44.1kHz or not.  With either the coaxial or optical S/PDIF connections, this sample rate appears to be supported.

 

I suppose it depends on what connection you are using.

Hi, are you using USB output? The reason I ask is that many albums on HDtracks.com are only in 24/88.2 format which apparently is not supported by HDP. If you do get output, I wonder what is being done to that signal? (I actually have the "HD" version so USB is my only option)

Ah, I have been using optical input. Have not tried usb. 

As mentionned a few pages back, my usb-fed HDP is hissing rather nastily when connected to my lovely Atoll amp. I was wondering : since I have a Fiio E10 lying around unused, would using is as a USB - Coxial converter solve my issue ? Or would it further degrade the sound along the way ?

It doesn't hurt to try. It could be ground loops or messy usb power, or something else. 

"It doesn't hurt to try"

No, but it does mean shopping for a coaxial cable. While that might not be prohibitively expensive, I'd rather spare the time and money if it doesn't solve my problem, which the nuforce staff did think a ground loop issue when I got in touch with them.   

I'm having kind of a unique problem with my Icon HD, although I'm not exactly sure if it's a problem with the HD itself.  The arrival of my HD coincided with a project I've been undertaking to rip all of my CDs to my PC.  I've been doing this pretty much whenever I have free time at the computer, and I also happen to listen to music while I'm doing this ripping.  After some time with amp on (maybe a few hours), I start to notice a slight digital "scratchiness" sound to my music. If I let it go on long enough, it descends into a digital noise abyss that makes my collection sound like it's coming out from the bottom of a digital ocean.

 

The problem is FIXED if I unplug the USB and plug it back in, so I'm guessing it has something to do with how the computer assigns resources to the amp vs. the CD ripping.  Could this problem be caused by some sort of "memory hog" (not sure if that's the right term) from the CD ripping? I've tried google searching to see if there's any kind of setting I can change to prevent the USB audio from degrading but can't find anything.  Has anyone else experienced this problem?

That sounds like a pretty good guess. I've had similar kinds of problems when trying to do too many tasks. There's memory bog down and usb driver errors. It could also be related to a power issue, as a spinning cd drive can eat up a lot of power. So does ripping for that matter.

 

What program are you using to rip? You might want to be careful that trying to do too much while ripping isn't messing with the quality of your rips.

I'm using Exact Audio Copy and I've been relying on the "all tracks accurately ripped"/"no errors" to ensure everything went as it should.  I hope that's good enough!  I have a pretty good PC and don't do much while I'm ripping except listening to music.

hmm.. I think I definitely have a problem.  I just tried leaving the amp on for a few hours without doing anything on the PC, and when I came back to it the sound still had that distortion. Guess I'll email Nuforce.

I explained my problem in detail to Nuforce and received this response:

 

Sometimes a ground loop condition can form in the USB bus, which normally, symptomatically is resolved with the uDAC as you describe. Often times with the uDAC using a powered USB hub can resolve this issue. This typically doesn't happen with the HD, or HDP, but you can go ahead and try this and it might fix it.

 

Does this make sense?  I did some investigating on "ground loops" and it appears that sound is more like a hum or a buzz.  This sound is nothing like that, it's like a digital or robotic distortion.  I searched for powered USB hubs and they are $25+ so I don't want to waste my time and money getting a powered USB hub if this has nothing to do with my problem.

Have you tried different USBs on your computer?  Some of them will be better than others assuming your using a PC

 

Funny you should mention this.  I have three USB 2.0 ports, and I actually did try switching to another port and got the same problem.  So I (hastily) eliminated that as a possibility.  But just for the hell of it I tried the third port, and so far so good!... fingers crossed.

 

One interesting thing I noticed: with the first two ports, the DAC was recognized instantly as "Nuforce Icon HD" which is what showed in my sound properties.  On the third port it actually didn't recognize the DAC at first and eventually showed up as "USB Audio Device"/"Default Device".  So I'm not sure if it's a USB problem or perhaps a Windows driver problem.  In any event I hope it stays fixed.