Digital Playback Comparison


Which sounds better: Original CD, CD burned from harddrive, playback from computer HD through USB, or optic cable, or Airport Express? I cleaned my contacts, installed NOS Amperex tubes in my preamp, had new tubes installed in my Trivista SACD/CD player, and had a go at a comparison test for these playback methods. The HD used was from my MacBook Pro. The piece of music used for a comparison was the Hallelujah chorus from Handel's Messiah, Solti and the Chicago Symphony Orchestra and Chorus (Decca 1985). See my system for equipment used. The USB playback was via a HagUSB via S/PDIF into the Trivista coax input. Here are the conclusions, going from best to least good sound quality:

1. (Tie): HagUSB and Burned CD (CD was burned from HD at 4x, from Apple Lossless file). I couldn't tell a difference between these two after extended listening including other music besides the test music. Great dynamic range, wide and deep soundstage, a "rightness" to the sound (at least within the limitations of digital) that made you want to quit analyzing and just listen.
2. Original CD. I read somewhere recently (some of you might know the source) that there is an explaination for why burned CD's sound better than original, but until I made the comparison, I was skeptical. The original had a slight loss of "presence", and seemed slightly compressed compared to the #1 playback methods.
3. HD through toslink. 1 & 2 are closer in sound than 2 & 3. There is a noticable shrinking of the soundstage and air with the optic cable. The cable is a good one--Van den Hull glass cable with mini-plug out from Mac. I was disappointed in the sound from this method.
4. Airport Express and optic. A significant drop in sound quality here. If you have been using this method I suggest doing what I will now do which is run USB out of computer to HagUSB ($119) via long run of coax (Canare for me) to your DAC. The Airport Express is OK for "working around the house on the weekend" listening, but is a serious compromise from what you can get with only a minimal incremental investment.

Notably absent from this comparison are music servers, or a good quality USB DAC, or good reclocker/converters that could be used with a computer HD and conventional DAC. Hopefully someone else can do comparisons of the burned CD with some of these methods to see what is the best sound for, let's say, a $2000 or less investment (obviously not including the cost of a computer). That is a level that many of us might be willing to make if there is a significant improvement over the #1 methods above.
bruce_1

Showing 2 responses by audioengr

Vcoheda - simple, the difference in the burned CD is that the pits are more accurately place, which results in more accurate timing, which reduces jitter over the orginal CD. Digital playback comprises the data, which is generally error-free and the timing.

This is really old news. Read the forums over the past 3-4 years. There are products such as Reality Check that rewrite CD just for this reason.

Jitter is what has always been wrong with digital playback.

Steve N.
Empirical Audio
Johnnyb53 - your understanding of USB is wrong. Except for asynchronous interfaces, most USB intefaces are synchronous, and depend on the rate of the datastream in real-time. The thing that makes some USB converters better than others is the chip that is used for the conversion, which can lower jitter significantly, the clock in the converter, and the implementation, or design.

Steve N.
Empirical Audio