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Positive Feedback ISSUE 61
may/june 2012


Computer Audio on the Cheap! Another view… Part 1
by Steve Lefkowicz


I think anyone who has ever read any of my articles knows my penchant for low cost gear. I make no bones about the fact that I actually enjoy finding low cost ways to get high quality musical reproduction at home. I also tend to prefer simple solutions, and think too many audiophiles needlessly complicate things way beyond what is necessary. With the growth of computer-based audio, I figured it was time to see what I could do to get into this without breaking the bank or getting too complicated.

How un-audiophile of me…

This all started about a year ago actually, when the company my wife worked for decommissioned several of the IBM notebooks that had been in use by their field technical staff. They made them available to employees for just $50, so we bought one. They were several years old, but the one we got was in good shape, not too outdated, and one model series newer than what I had when I worked there. So, now I had a "music server" in the form of an IBM T42 notebook (Intel Pentium M 1.70 GHz processor). Unfortunately, it only had a 30GB hard drive, 1 GB of RAM, and no operating system, but it was as start.

The first step was loading up an operating system. I thought about variations on Linux, but am fairly ignorant of Linux's operation. I felt that in keeping with my idea of simplicity, loading Windows XP Pro (SP3), which I knew well, and used on all the other computers we have, made sense. I did a manual install, and only loaded things I felt were necessary.

For a hard drive, I had considered an Iomega 1 TB USB drive, as I had purchased one for our desktop computer to use as a backup and photo storage drive. That was only $89, but I had an extra 200 GB drive that wasn't being used and decided to use that instead. It was actually a standalone USB drive we bought as our original photo storage drive, but it failed shortly after we set it up. That turned out to be the USB board in the case, not the drive itself, and removing the drive and installing it in an aftermarket USB case purchased for $20 solved that problem. Formatted for NTFS, I had my external USB drive for my new server!

So far, total expenditure - $70!

However, I then lent the notebook to my son to use until we bought him a new one to take to college. So the project sat on hold for several months.

Once I regained use of the notebook from my son, it was time to start the music server project again. Of course I loaded iTunes. It's free, easy, and I already had a large iTunes library on the notebook I use daily. That library is almost all 320 kbps files from my CD collection, and used to sync my iPod Classic. I decided not to put any compressed files on the new server (at least no lossy compressed files), so configured iTunes on the server to Apple Lossless and started loading my CD collection. I have about 2000 LPs, but only about 600 digital disks. I just started at one end and loaded in alphabetical order, skipping disks that I new I wouldn't be in any hurry to play. After a few weeks, I had about 400 CDs loaded. It was time to try the system out!

Not having an iPhone or iPad, and using an iPod Classic rather than a Touch, meant I didn't have a small device to use as a remote. However, since I always seem to have my personal notebook with me in the house (a six year old Dell E1505) I resolved the need for a remote by loading up the free version of Team Viewer ( on both notebooks. TeamViewer gives full control over the remote computer in a window on the host, so I could do whatever I wanted, both with iTunes and any Internet web sites I wanted to use. I am a big fan of Last.FM for streaming background music, even if it is too low resolution for serious listening. TeamViewer made all that very easy.

The only USB DAC I had handy was my trusty old original issue Headroom Total Bithead headphone amp. It is limited to 16/44 playback, and only has a mini headphone jack for analog out. A quick trip to Radio Shack for a mini headphone to RCA cable (about $12) was all that was needed to get things going.

Don't get me wrong here, I love the Total Bithead, and use it probably more that my full audio system with my iPod and a pair of Beyerdynamic DT770 Pro 600 ohm headphones. It does a great job driving the headphones, and allows comfortable listening for extended periods. I've also used it extensively connected to my notebook via USB, for both listening to music and while playing DVD movies. But now, hooked up to my regular audio system, though okay, it wasn't really what I hoped for, and certainly not something to replace my Marantz SA8001 SACD player for regular listening. Everything sounded kind of thin, lifeless, lacking energy, and certainly lacking in bass power.

Obviously a new USB DAC needed to be tried.

I did a quick search to find something that had potential of pretty decent sound, while keeping the price low. I decided to base this first choice on other people's opinions, and after talking to a few fellow PFO contributors, decided to ask CEntrance for a DACport LX. The LX is the DAC only version of the DACport that has received great reviews as a USB DAC and headphone amp. By giving up the headphone amp, you save $100 ($299.95 for the DACport LX compared to $399.95 for the DACport. Bundled with their $75 Reserve Series Y Cable, the total price comes out to $349.95. That sounded like a good deal to me, provided everything sounded good, of course.

The CEntrance DACport LX seems to fly in the face of audiophile tradition and expectation. It is not overly large or heavy. It doesn't have a half-inch thick, brushed aluminum faceplate or rare, exotic materials. It doesn't possess any mysterious newfangled take on the world of physics. It doesn't have a power supply big enough to operate industrial power tools. What it does have, based on a couple months of daily listening, is some solid, sound engineering. In other words, this little thing works, and works well.

It certainly makes things easy and uncomplicated. There are no drivers to install or any setup at all. Plug the USB input into an available USB port on your computer, plug the other end into any available line level input on your preamp or integrated amp, and start listening.

A few things do need to be considered, though. For one, it uses a mini-USB plug on the input side, precluding the use of most higher quality USB cables. I used the USB cable that came with it, which at six feet, was long enough to make placement in the system very easy. The cable had what appeared to be a ferrite core or filter at each end. I had no other cables handy that would appear to be any better quality, so swapping out wasn't an option.

Some audiophiles might be concerned with the use of a ¼ inch stereo headphone jack for the output. It certainly precludes easily using your choice of cables. The CEntrance Reserve Series Y Cable bundled with the system for an additional $50, seems very well made, used good quality connectors, and was the only cable I used in the system. I did have a ¼ inch to RCA adapter, but since it had about four inches of really cheap cable between the plugs, it just didn't seem like a good idea. If I can find a better quality adapter at some point, I'll report on using that with more expensive cables between the DACport and preamp.

Rather than view this as a formal review, commenting on specific CDs (or I guess I should say, files) and careful note taking, instead, I just set it up and started using it. Actually, and though it may sound silly to many of you, what I did was make a playlist in iTunes called "Songs Not Yet Played" and dragged everything into it. Most listening sessions consisted of setting iTunes to shuffle, and playing from this playlist. Every hour or so, or at the end of each session, I would delete all the tracks that were played from the list. As of this writing, I have listened to about 1300 tracks through the DACport, none more than once.

To say I was more than a little surprised at the sound quality from this setup would be somewhat of an understatement. Truth be told, I didn't have really high expectations for my initial computer audio system. I had expected it to be merely okay, but not up to par with, or competition for, my Marantz SA8001 player. For those who aren't familiar with this particular Marantz model, it was their second generation SACD outside their Reference line. First they had the SA8250 multi-channel SACD player, which sold for about $1100 and was a Class A rated product in Stereophile. I had one of those, and thought it was quite exceptional. It really sounded quite nice on both SACDs and redbook CDs. However, that model had a history of issues, mostly with failures in reading hybrid SACDs. I replaced it with Marantz's next model, the two-channel SA8001 ($999) that was actually a noticeable improvement in sound quality on both SACD and CD. The SA8001 is one of those products that is just a joy to use, and has provided me with years of musical enjoyment. The SA8001 has now been replaced by the SA8004 (still $999), which I have not heard. Some people have said it betters the SA8001 in some ways and not in others, but obviously I can't say one way or the other until I try one for myself.

In addition to playing from my Songs Not Played Yet playlist, I also queued up several CDs in my Marantz SACD player to directly compare the original disk to the Apple Lossless file on the server. The output levels of the two were very close, and a quick nudge on the volume control of the preamp was all that was necessary to match them closely enough for comparison. I really hadn't expected the results to be so close. Whether playing through the Direct Acoustics Silent Speakers/Adcom GFA535 combination or the Tekton Lore/Antique Sound Labs MG-15DT-S setup, or whether I was using my trusty old PS Audio 4H preamp or the wonderful new Rogue Audio Perseus Magnum preamp, the end result was the same. And that result was that the server files through the CEntrance DACport LX were about 98% the same as through the Marantz. Yes, I know that number is meaningless, but I use it just to get the point across that the similarities in sound between the two playback systems were far greater than any differences I heard.

The biggest differences I could say I reliably heard were with the Marantz being ever so slightly more dynamic in the upper/mid bass, but only on those tracks that were already quite notable in that area, and maybe also being a little more transparent in the uppermost couple of octaves. But even here, the differences were quite small, smaller in fact, than the difference between the Nordost and Radio Shack speaker cables I tried with the Tekton speakers. The differences were far smaller than the difference between the Marantz and the old AMC CD player I used for years before getting my first SA8250. Sometimes holding on to old equipment comes in handy, even if it's just to fire it up for a day to do a quick comparison.

The differences are small enough, that the only times I've used my Marantz for about the last two months have been to listen to SACDs, or for the specific purpose of comparisons for this article. The sound of the Apple Lossless files, and more importantly, the few 24/96 files I now have (especially the early King Crimson releases from DVD-A files) have been thoroughly enjoyable.

I know that audiophiles love making things both complex and expensive. I'm sure some of you reading this will scoff at my lack of a USB to SP/DIF converter, or my using a DAC that runs off the USB power supply, or not having 8 GB of RAM or a solid state hard drive. What can I say, other than to point out again that I am dedicated to getting the best sound possible at the lowest price. I've done the high priced stuff in the past. It's kind like owning a sailboat, otherwise defined as having a bottomless hole in the water that you try to fill with money. Been down that road, too. I don't view this as a competition, and don't really care if someone's more expensive system sounds better than mine. I've heard plenty that do, and plenty that don't. We each take our own path through this hobby.

I'll have more to say about the DACport LX in the next installment of this series, and will compare it to another low priced USB DAC, but so far, I have to say that I am actually quite surprised by how nicely this setup is working.

IBM T42 Specs (2004 vintage):
Pentium M 735 – 1.7 GHz, 2MB L2 cache
15-inch SXGA+ (1400x1050) TFT Flexview Display
64MB ATI Mobility Radeon 9600
30 GB, 7200 RPM hard drive
Intel PRO Wireless 2200BG
Windows XP Pro
200 GB 5400 RPM Western Digitial HDD in an External USB Case

CEntrance DACPort LX specs:
Digital specs
Sample Rate 96kHz (Also: 44.1 kHz, 48kHz and 88.2kHz)
Resolution 24-bit (Also supports 16-bit)
Connection USB1.1 or 2.0, driverless
Communication AdaptiWave™ - our proprietary USB technology
Local clock 10 ppm precision, 1 ps jitter
Compatibility Any computer running Mac, PC, Linux, or iOS

Analog Specs
Frequency Response 20Hz... 40kHz +/-0.2dB
Dynamic Range 113 dB, re +12 dBu, max gain
THD+N 0.0018% / -95 dB (FS, 1kHz)
Noise Floor 7 µV RMS (A-weight), max gain
Audio Output Stereo 1/4" jack
LX output level +6dBV

General Specs
Input power USB bus (no external power supply needed)
Internal power supplies ±9V, super-clean, dual analog rails
Unit Dimensions: 4.5" (11.4cm) L, 1" (2.5cm) W, 1" (2.5cm) H
Weight: 2.5 ounces (72 grams)