| Apogee PSX 100 24-bit/96 kHz A/D Converter |
|
|
| Monday, 01 January 2001 | |
|
Page 1 of 2
Introduction You
may be thinking, "Jerry, why are you reviewing a DAC? Everyone knows
that DACs are an integrated part of AV preamps these days." I must
admit that, while I own a pretty badass AV preamp (Proceed AVP), when I
merged my dedicated music system with my theater system, I suffered a
number of musical maladies. At the time, I had also moved all of the
equipment to an entirely new room with all sorts of acoustic problems,
including but not limited to a glass front wall and a 20-foot by
eight-foot-tall mirrored left side wall. The result was a room that
sounded understandably bright.You may consequently ask, "Hey, Jerry, why did you move to such a joint?" The answer is, the view, my man. Imaging is defined by being able to see from the Capitol Records Building to Catalina Island while jamming out to your system, but I had lots of work to do to get the music right. I got Bob Hodas back in to do my placements, moved my gear out of the way and placed it into a custom rack. I installed a motorized set of blackout drapes that are four layers thick and very absorbent sonically. I had my new drop ceiling packed with over $1,000 worth of insulation – which is quite a bit for a 15 by 20-foot room with a six-inch drop ceiling. The Hodas setup really helped. Hodas took a lot of the zip or brightness out of the system in the room, but the addition of this Apogee professional DAC and A to D was an embarrassing reminder of how much I missed having a high-performance dedicated DAC in my digital loop. I have my Apogee PSX 100 at the tail end of my digital rig, which starts with a Theta Data Basic ($2,400) CD transport, fed digitally via AES EBU to a z-systems RDQ-6 ($7,500) six-channel digital EQ and 24-bit upconverter. I also have a coax digital feed from my Pioneer Elite DV-05 ($1,000) DVD player running into the z-systems digital EQ for 24-bit DVD-V music, which also allows me to listen to CDs. From the rdq-6, I feed the Apogee PSX 100 via another AES EBU cable. From the Apogee PSX 100 DAC, I run an analog signal into the balanced input of my Proceed AVP, thus avoiding internal digital conversion. Another hard lesson that I learned was that a $10,000 CD player costs $10,000 for a reason. If you sell off your DAC (as I did my Mark Levinson No. 36s), you can’t really expect the same sort of extreme digital performance from an integrated product, such as the $5,000 Proceed AVP preamp. This is not to say that the DACs in the AVP are bad. Indeed, they sound very good for all but the absolute best systems. In my case, my system has gotten so high end that, for music, the addition of a $2,995 DAC actually makes sense and delivers a quite significant sonic improvement. Additionally, the Proceed AVP won’t allow digital looping, which prevents you from hooking up a digital EQ like the z-systems. The addition of digital EQ and upconversion also helps the system dramatically by allowing room correction EQ and 24-bit re-dithering of your CDs. This is of specific importance when you consider that the Apogee PSX 100 is a 24-bit DAC that should be fed with something other than audiophile geek recordings. The PSX 100 is a professional audio product. Priced at $2,999, it is a rack-mountable digital-to-analog and analog-to digital-converter. The meaning of this is different for the audio/video enthusiast than it is for the audio professional. The PSX 100 will play the role of host to slews of digital inputs, ranging from (2) AES EBU, SPDIF, TOSLink and more. The A to D section will take analog signals from, say, your VCR, PVR (TiVo or ReplayTV), or even your turntable, and convert them to a high-quality digital signal. In this way, the Apogee PSX 100 becomes a sort of switching device for some systems, although it is not controllable by RS232, which is needed to communicate with a modern control system like a Crestron or Phast. Digitally, the PSX 100 is one of the most sophisticated D to A converters available. The analog section is of the highest importance in the PSX 100. Issues of board design and use of matched components make up the design mantra. Apogee also uses toroidal transformers to create DC to avoid RF noise and hash that pollute the analog signal. The digital section is built around accurate clocking and reclocking of the digital word to avoid dreaded jitter. Jitter can be a nasty little bitch when it comes to your music. Most digital signals are heavily damaged by factors ranging from noise from AC or DC to bad cabling. Apogee binds an internal clock to the digital signal, so that the DAC’s timing is improved over the incoming signal. Apogee claims that their system improves the clarity of the high frequencies and the stereo image stability, while also achieving some tightening of the bass. |
