Review: Empirical Audio Pace Car 2 Transport

Category: Digital

WHAT IT IS: The Pace Car 2 is a reclocker. It accepts a streaming digital input via S/PDIF or Toslink at 44.1 kHz or 96kHz, discards the timing data, reclocks the audio data with a high precision clock, and outputs a low-jitter data stream via S/PDIF, AES/EBU, or I2S.

MY SYSTEM: LaCie d2 Quadra→firewire 800 cable→iMac→ethernet cable→modified Sonos ZP90 with slave clock→DH Labs D-75 digital interconnect + master clock cable→PACE CAR→DH Labs D-75 digital interconnect→Meridian G68 processor→Gabriel Gold Rapture analog interconnect→Pass Labs X250.5 amp→Gabriel Gold Revelation MkII speaker cable→Focal 1007be + a JL Audio Fathom 113.

Power conditioning is a Shunyata Hydra 8 and a PS Audio Duet. I use Shunyata Pythons on the Hydra, the processor, and the amp. I use a variety of vibration control devices from Gingko, Mapleshade, and Black Diamond Racing. I have done extensive EQ work using Meridian Room Correction and Room EQ Wizard.

MY PACE CAR OPTIONS: My Pace Car 2 came with an S/PDIF input, an S/PDIF output, and an Audiocom Superclock 4. It is 44.1 kHz only. The master clock in the Pace Car controls a slave clock (custom installed by Rick Cullen) in a Sonos ZP 90.

Before I added the Pace Car to my system, I ran a USB cable from my computer to a USB to S/PDIF converter, and then ran the S/PDIF cable to the Meridian G68 processor. The G68 is said to reclock incoming digital data to minimize jitter. Apparently, there are several methods of reclocking, and some are more effective than others. The Pace Car uses a FIFO buffer, which temporarily stores the digital data stream for reclocking before sending it to the downstream DAC. I cannot talk with any expertise on the benefits of using a FIFO buffer in contrast to, say, PLL’s (which I believe are what is used in the Meridian G68). What I can talk about is what I heard when I installed the Pace Car in my system. So without further ado…

It is awesome! The Pace Car has transformed my system in at least four areas:

1. RESOLUTION. The perceived resolution of my system has significantly increased. I say “perceived” resolution because my system is still only 16/44.1, but the Pace Car has revealed a whole new level of detail to me. I assume it is detail that was formerly being masked by the frequency modulation created by a high-jitter input. Whatever the reason, my system has a greater level of detail than ever before.

2. IMAGING FOCUS. Images have become much more clearly defined. Before the Pace Car, I could hear the general locations of instruments in the room. With the Pace Car installed, I can hear the “boundaries” around the individual instruments. This helps create the illusion of hearing a real musical event.

3. HIGH FREQUENCIES. This is probably the change I am the most excited about, because it’s a particular sensitivity of mine. Before the Pace Car, my system suffered from a certain amount of “ringing” in the high frequencies. I wouldn’t exactly call it brightness, but rather shrillness. It was slight, but bothersome. The Pace Car has virtually eliminated this problem from my system. I think this effect contributes to the common perception that a low-jitter signal sounds more analog.

4. NOISE FLOOR. I don’t exactly understand why this would be, but adding the Pace Car reduced the noise floor in my system to an all-time low (and it was pretty low to start with). During late night listening sessions, with a good recording, the space between the notes sounds like the system is turned off. Very satisfying.

So is there a downside? Sonically, not that I have detected. I do, however, have one complaint. It’s aesthetics. The Pace Car is not very good looking. It looks more like pro gear to me. Some may like that. I would prefer it with a sexy silver faceplate. This may be shallow of me, but there it is. I suppose putting it in a pretty box might make the unit too expensive, but it would also make it look more at home on a rack with the kinds of components with which (I suspect) it is usually mated. But this is a quibble with what is otherwise an excellent product.

One final note about Steve Nugent from Empirical Audio. He was extraordinarily generous with his time and expertise during the process of selecting a device to meet my needs. I don’t know how he finds the time to do that while designing and building his own products, but it was enormously helpful. I now have the convenience of a computer based system and the sound quality of a high end transport. Dollar for dollar, the Pace Car has made more of a difference in my system than any other product I have purchased.
Thank you for your review of a product that most of us would not get any feedback about from an actual user.
It is a very intersting product.