First, a Word from Your UV22 Sponsors
Bits translate into dynamic range, where more equals more. When the sound level drops below the resolution of the last bit (LSB, or "least significant bit"), a form of distortion occurs. Dither is an analog noise added across the entire frequency spectrum to maintain the program level above the LSB. Noise shaping tailors that noise to the frequencies that our ears are more sensitive to (generally speaking), so that less noise can be used and a more transparent displacement of the digital distortion can be achieved.

UV22 is based on the concept of creating a dither signal in the inaudible area of 22 kHz. UV stands for "ultra-violet," the connotation being higher frequencies, and the "22" refers to the 22 kHz. "To create a carefully tailored super-audible dither system, Apogee used an algorithm to generate the dither information rather than relying on noise shaping," according to John Nemeth and Richard Elen of Apogee. They go on to say, "The UV22HR [a "high res" version of UV22] dither signal is generated over specific periods, during which the quality and statistical accuracy of the signal are carefully controlled."

The goal of the process is to allow the listener to hear coherent audio below the theoretical noise floor of a 16-bit system, which is -96dB. One other thing to note: UV22 does not operate at higher sampling rates. This was considered and rejected, since it was assumed that bit reduction would never be called for at higher sampling rates (unless, of course, the sampling rate were reduced also). This may be Yamaha's reason for not creating an SRC for 88.2 and 96k.

We're Going in—Analog
Archiving some LPs seems like a good place to start, giving us the opportunity to check out the A/D converters with and without UV22. I grabbed my Miles Davis "Jack Johnson" album, which is in very good condition, and placed it on a Technics turntable with a Shure cartridge and needle that has about 30 to 40 hours of play time on it. I'm simply taking the record outs of my JVC receiver to the inputs of the CDR1000. The CDR1000's analog inputs are XLR, with a -10/+4 dB operating level switch. The manual recommends, when using an unbalanced signal, connecting the shield and the ground on the XLR plug, so I pulled out my soldering iron and made the proper cables.

I placed the blank CD-R into the tray. The CDR1000 analyzed it, looked for evidence of a TOC or temporary TOC (a finalized or unfinalized CD), and in a few moments told me that it was a CD-R on track 1 (unfinalized blank CD). The unit also does an OPC or "Optimum Power Control" test to determine the optimum laser power necessary for recording. I put the CDR1000 into record pause, set my level to 4 o'clock. At this setting, the peaks on the signal came to just below 0dB. I recorded the first side of the LP without the Apogee UV22 engaged, and the second side with it engaged. This Miles Davis album has one "tune" per side, so I let the CDR1000 auto ID. After recording, I finalized the CD, a simple procedure that took less than three minutes.

The 20/24 bit, 48k Side of Things
It's my assumption that the most real-life utilization of the CDR1000's features is in an ADAT to Digital console scenario, where the CDR1000 is receiving a 48 kHz sample rate at 20 bits and converting on the fly. I don't have that type of setup, so I decided that I would replicate it with my DAW in order to test the digital inputs of the unit. Similar scenarios would be the multitude of standalone multitrack digital workstations, most of which are doing 24-bit recording these days, but still at 44.1 or 48k sampling rates.

The CDR1000 took whatever I threw at it. I used manual ID when transferring, as it's relatively easy to miss the very beginning "breath" of a musical piece when using auto ID. This is true for DAT, or any other device that can auto ID, and it can certainly depend on the piece of music. In general, operating the CDR1000 was rather flawless.

Listening Is the Key
We're doing two things here, converting the sampling rate, and also the bit depth. Sample rate conversion seemed quite transparent, as I I could discern no apparent anomalies or artifacts from the conversions, either from DAT or from computer transfers. The bit reduction using the UV22 technology is audible, in a subtle yet profound way. It's most clear in the quieter passages, where there's definition greater than when no UV22 is applied, and also greater than a recording that was originally 16 bit and requires no bit resolution. This increase in definition is greater when reducing 24 bits to 16 than when reducing 20 bits to 16, as it should be.

Okay, Wrap It Up Here..
The CDR1000 comes in with an MSRP of $1,799. It seems a little pricey, but I can't really give it a less than 1:1 price/performance ratio. Quality mixdown decks cost that much. Yes, I'd like to see 88.2 and 96k sampling rate conversion on it for forward compatibility. Other than that, the CDR1000 offers a wide array of professional features, with all the markings of being an invaluable tool in a variety of studio situations.

JD Mars is the producer of Digital Pro Sound, and possesses a reasonable amount of soldering skills.

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