PC audio with USB DAC

Hello all:

With my digital library of music expanding to almost 10,000 songs now and the fact that I work at home much of the time, I have the desire to improve my computer audio system.

I tend to use 320Kbps AAC files or mp3 files with a few FLAC files for auditioning.

I have a laptop, so starting from nil. I am a neophyte to computer audio and as such have been reading about USB DACs.

I am ready to upgrade the speakers to a set of decent powered desktop units (Audioengine 5+)and a subwoofer (Audioengine S8)and wanted to start with a USB DAC. I have a small Classe preamp and amp, but don't want to have too many things to turn on at the computer to get good music sound. Please don't consider this slumming, it's a brave new audio world :-)

I decided to acquire the Nuforce Udac2 SE.

The sound is definitely more dynamic. The lows are stronger, the mid range is clearer and the highs are higher to my untrained ears. My problem is around the convenience factor.

A USB DAC doesn't become active until the USB port and the DAC driver are initialized. This simply means that you can't hear boot alerts and such. Not that big a deal I guess for premium sound, but I wondered if anyone had any comments about that.

Also the need for drivers which in my short experience appear to have problems. While I had the Udac2 SE in my system, I found that in the middle of a song, the music would stop and I would get a loud white-noise hiss or popping sound or staticky sound...all disconcerting.

After a couple of days of screwing around and getting aberrant behavior, I returned the Udac2 SE.

I'm sorry this was a long message, but I am very interested in other's experiences and any hints.


What are you using for music playback? ITunes? The best computer playback performance is attained when you can optimize the computer playing the music, and when you can dedicate the computer to only playing music. What operating system a you using, there are several guides created by various DAC manufacturers that tell you how to optimize your system for music:
This is one example.
Audioengine is a great brand to start with, they also have a USB DAC you might want to try.
I think your playback problems might have more to do with the setup on your computer than the DAC you are using. TIP: If your music library is on an external hard drive, and you are using a USB DAC, try to use a firewire external drive, having both the drive and the DAC on the USB bus might overload the computer's innards and cause the problem you've described.
Computer audio takes some tweaking, but it's very rewarding when you get it working! Don't give up!
sounds like you want to stay mainstream (compressed music). Consider the Sonos system with the Wyred4sound DAC upgrade.
I have a pair of Audioengine 2's attached directly to my iMac. I don't use them for music listening, but my only real complaint is that they are very sensitive to RF interference... so I can't set my cell phone near them.

If you're concerned about file quality, find an ABX tester app, down convert some flac files to AAC at a few different bit-rates and see at what point you can start telling the difference.

I haven't had any issues with my Macbook Air interfacing with my USB DAC (Music Hall DAC15.2), so I can't be of any help on that topic other than to say that the 15.2 packs a lot of bang for under $300.
Every USB interface and USB DAC is different. Different performance, different drivers etc..

It is important to understand the type of USB interface and the optimum playback software and computer hardware to use with it.

Here are some tips:


Steve N.
Empirical Audio
You reference to needing to install drivers for the DAC suggests that you are using Windows, not a Mac. Let us know if that is not correct. You need a Windows person to tell you how to best adjust your sound settings, I think. You shouldnt' be having hissing and popping, and you should be able to redirect the alerts to the computer's speakers. Unfortunately, I don't use Windows anymore, so I can't be of much use.
Thanks for the input everyone. I love to see a vibrant community with passion for music and practical experience on how to get there.

I should have mentioned my system type
Thinkpad W520 (Quad Core CPU), 8GB RAM, Win 7 SP1.
This is a traveling laptop, so not dedicated to any one thing.

I am currently using iTunes but am evaluating Jriver Media Center 17 (and am pissed that it is screwing with my library--and placing a hundred songs into "unassigned" artist. I just got to where I understand how itunes does it, but I digress...

Using internal 500GB hard drive for golden master of library. Have a NAS with a mirror image for streaming to the rest of the house. I may allow that NAS copy to be my golden master, but this is a laptop and I travel with it. I can use the iPhone for music on the road though.

Davide mentioned evaluating the Sonos system. I looked at it but not seriously. The prices for multiroom music made me look elsewhere. I may very well come back to it as time goes by.

I am interested in best value for the buck in both equipment and filesizes. I just want to make my traveling laptop sound great while I'm docked at home. I just bought the AudioEngine 5+ which is shielded so should work as a pc desktop speaker. I also bought their D1 DAC with volume control for the desktop. I will evaluate them in that configuration then probably buy their S8 Subwoofer after the bills clear :-)

I have ripped some lossless, but it is so reliant on the recording that I need to rip some high quality recorded CDs to make that serious evaluation. In the meantime I have experimented with mp3 320K and AAC fixed 256 and fixed 320 and VBR 256. I have no confidence that I can discern a listenable difference. I expect to get more serious after the upgrade mentioned above.

I am open to your experiences and a good happy medium to use beyond the obvious (lossless rips).

I am especially interested in replacing itunes. I really like the flexibility of Jriver MC 17 so far, but am prepared to eval more. I need iphone and ipod support and a good usable UI.

I am also happy to share my experiences with Jriver for those that are interested although this may fit better in a different forum section.

Some thoughts:
If all your music is on your hard drive, and you are working on your laptop while playing music through your USB DAC, I suggest you get the music off of your hard drive and onto an external drive, because your hard disc gets hit a lot as you work on stuff, and this gets in the way of the audio signal.
External drive should use a different bus than your USB DAC, as I posted above.
iTunes does not load music into RAM and playback from RAM, it hits the drive where the music is stored (I think). JRiver has a check-box to playback music from memory, try checking this box to get rid of ticks and pops. Also adjust the buffering from the default 6 seconds to 10 or 20 seconds, if you can stand it. This is all under tools->options->settings.
Hearing a difference between lossless and lossy file formats is highly dependent on the quality of compression, the signal path/settings in the computer, and the quality of the system you are using, there are many, many variables.
I doubt you need special drivers, Windows 7 supports audio output up to 24bits/96kHz. If you get into some 24/192 or 24/384 high res files, from HD Tracks and the like, you might need special drivers, depending upon your DAC.
One more thing, at the risk of angering the budget audio gods, I have found that the USB cable counts. Big time. I have heard a vast difference in sound quality between USB cables in my system, I suggest Pangea PC, they are cheap, $25 for 0.5m at Audio Advisor, silver plated copper cable. You can return it if you don't hear an improvement over stock USB.
Sheesh this post is getting long, sorry about that. JRiver will also auto-detect the bit rate and sampling rate of your music track, and will adjust its output to match. iTunes will not do this. If you are only running 16/44.1 music rips, do not allow Windows to up-sample that output. Let your DAC do it, and set windows to output 16/44.1, if your DAC will take it. You want the computer doing as little as possible to the audio signal, turn off all processing.
Some other thoughts:

1) USB cable is important, but never buy a digital cable of ANY type less than 1.5m in length.

2) Sonos is a great product functionally, but the audio quality is poor. Needs reclocking, which can be added at more expense. Good 1.5m S/PDIF cable is critical.

3) Never use iTunes on PC, only on Mac, and even then make it sound better using several tools such as Amarra, Audirvana, Pure Music etc.. Jriver or Foobar2000 are good choices and can be improved by adding Jplay.

4) If you are using an inexpensive preamp or receiver, this will likely mask the differences between audio formats, data compression and sample-rates. Best to eliminate it or replace with a passive transformer linestage.

Steve N.
Empirical Audio
I knew that applied for digital coax, was not sure about USB, Steve. I have had recommendations for short-as-possible USB cable from other designers of USB/SPDIF converters. I've skimmed your white paper.
Steve N.,

Reading your summary above, the only items that is not clear to me is the digital cable length. I am having difficulty seeing where a 1.5M cable is more efficient then a .5 M cable in delivery digital content. I am open to the argument but --- I just cannot see where electrons traveling 10M is better then .5M for quality. I am not an audio expert by any means, and am open to a solid justification.

Only other comment -- Fidelizer vs. Foobar or JRiver on a PC -- your thoughts?

Thanks for the link to the Benchmark audio setup page. My DAC 1 USB settings were at 48khz. MUCH better at the 96khz. Doohhhhh!
Sbleam - the longer cable is required for good performance of ANY digital cable, USB, S/PDIF, Firewire or I2S.

The length requirement has to do with signal reflections, a digital-specific phenomena and issue. Read this white-paper for an analysis:


This has been independently verified through AB/X tests by UHF magazine in Canada.

Now if the cable is less than 8 inches, this is also good, but not very practical.

Steve N.
Empirical Audio
Jsd52756, you're welcome, Wavelength also has a page with setup tips,


and don't forget to also visit Empirical Audio's page link, posted by Audioengr above.