Product Review - SONY PCM-R500 Digital Audio
Tape (DAT) Cassette Deck with SBM - June, 1997
by John Sunier
Click here for larger image
Sony PCM-R500 DAT Deck; Professional DAT recorder with four direct-drive motors; Shuttle and Jog Dial; Extensive interface options (including disabling SCMS copy function); Multiple menu modes; With 8-pin wired remote plus wireless remote; Independent Channel 1 & 2 record level controls; Analog Input/Output: Balanced (XLR), Unbalanced (RCA); Digital I/O: AES/EBU (XLR), Coaxial (RCA); Stereo phone jack with level adjustment; Parallel DIN 8-pin remote interface; Size: 5 3/4"H x 19"W x 14"D; Weight: 15 lb. 14 oz.; $1,700; Sony Business & Professional Products Group, Sony Electronics Inc., 3 Paragon Drive - S135, Montvale, New Jersey 07645; Phone 201-358-4197.
Very little original recording activity happens in the U.S. among audio buffs, whereas in Japan and parts of Europe it is a serious hobby. The primary area for recordists, aside from music events at high school and college level, seems to be the energetic pursuit of rock groups with DAT (Digital Audio Tape) and analog cassette recorders. Grateful Dead fans are at the vanguard of this effort, and their Dat-Heads web site will probably soon be bristling with discussions and analysis of this new Sony DAT deck. (They are at http://www.atd.ucar.edu/rdp/dat-heads.)
DAT recorders place the audio signal on the tape in the form of 1s and 0s (digital bits), just like on CDs, and you have the choice of recording in exactly the same sampling frequency (44.1 kHz) and word length (16 bits) as CDs, along with some other choices if you wish. The professional industry standard for DAT for the past several years has been the Panasonic SV-3700 deck at about $1,600, and Sony's R500 is obviously designed to meet this competition head on. Many classical and jazz original sessions are still recorded on the 3700, and it has wide use in broadcasting. A recent upgrade offered some improvements, but the R500 has the edge in several departments. Two that will most interest many recordists are, first, the built-in Super-Bit-Mapping function which, via digital noise-shaping, achieves in this 16-bit system a S/N ratio equivalent to that of a 20-bit system. It noticeably improves very low-level resolution (especially valuable in much classical and jazz recording). I have been recording with this feature for some time now using Sony's small portable SBM-1 unit which mates with their portable DAT recorders, the D3, D7 and D8. Here, it is an integral part of the circuitry, though it is defeatable if one should so wish (why I can't imagine, since no decoding is required to realize the sonic improvement of SBM on playback).
The other edge in Sony's model is that the Serial Copy Management System, which is part of all consumer decks, can be totally defeated during both recording and playback. Allowing only one digital-to-digital dub to be run off from a master DAT, and then blocking the record function from further dubbing in the digital mode, SCMS often causes recordists great frustration. They are forced to go through an analog stage in order to make multiple dubs, with the increase in noise and distortion which can be created. Even making digital-to-digital dubs, there are some subtle losses, but it is usually to be preferred to converting back and forth between digital and analog.
The large Jog & Shuttle Dial on the right side of the R500 is similar to that on the 3700, allowing for precise and fast finding of any spot on a tape in any direction. The four drive motors give a fast and precise spin to the tapes without the sometimes shrieky high-speed sounds experienced with the Panasonic. Also similar to the 3700 are the digital and analog ins and outs, the choice of three sampling frequencies (48 kHz, 44.1 kHz, and 32 kHz (the last in the half-speed format which doubles the storage on a 120-minute DAT tape to four hours at a reduction of the bit rate from a linear 16 to a nonlinear 12 bits). Sony also shares many of the methods of electronically marking the DAT tape with special sub codes at selected points for start, stop, skip and rewind functions. This is possible even after the tape has had music recorded on it, via a separate track reserved only for electronic indexing. The recordist can create an edited playback from the original master tape simply by programming the deck to wind forward automatically at high speed over sections he (she) wishes to eliminate. A sub code is always placed on the tape at the very end of the last recorded portion so that, using an End Search function, one can immediately go to the first unrecorded portion on a tape to continue with recording. Another pleasant feature lacking in the 3700 is Sony's separation of the left and right-channel level controls, allowing precise level matching vs. the single knob of the Panasonic. The ears for mounting in a professional 19-inch rack are part of the R500, rather than a bolt-on system as with the Panasonic.
Impatient audiophiles are doubtless saying to themselves by now, "Well, how does it sound?" In a word, great! With the heavy emphasis on the problem of jitter in CD players, transports, and processors during the past few years, another music source that can have worse jitter than the cheapest $159 CD player has been almost totally ignored. That's DAT decks, especially the big pro models. The Panasonic deck showed an immediate sonic improvement in transparency and resolution when its digital out was fed through my Audio Alchemy DDE v.3.0 processor and DTI v. 2 jitter filter rather than feeding my preamp directly from its analog out cables. The improvement was greater than I had heard upon adding a good outboard D/A processor to any CD player. However, when the jitter filter was removed from the chain, with only the D/A processor remaining, the sonics of the Panasonic fell to almost the original poor level. (Such a different was impossible to detect when the source was a good CD transport such as the Parasound C/BD 2000.)
Running the digital out from the Sony R500 through both the A.A. jitter filter and the D/A processor provided a very subtle gain in transparency, but with most music the differences between that and the direct analog-out feed of the Sony were negligible. For example, when making multiple cassette dubs from DAT masters (the best of them on a Dolby S cassette deck), I run the R500's analog out directly into the dubbing bus rather than using the filter and processors in the chain; the difference would not be heard on the final cassette playback anyway. That wasn't possible with the Panasonic without audible impairment of the cassettes.
The headphone amplifier is of fairly high quality; an improvement over that in the 3700 and with enough muscle to let my Grado SR-60 and 80s sing beautifully.
Another plus is the large and easy to read digital display. Anyone who has done even a modicum of digital recording has learned that going over the all-important 0 VU point in recording level spells disaster, i.e., the most excruciating distortion products. The recordist always wants to put the highest level possible on the tape, but unexpected peaks often come up during live performances of all sorts. It would be great to have a gimmick like some CD players, which automatically scan the entire CD or entire track and then repeat over and over the several seconds of the highest peak portion of music so recording levels can be adjusted. Well, the R500 has something even better than that. It constantly displays the smallest Margin between the highest peak recorded so far and 0 VU. So if you've come to the end of a session and the margin reads 2 dB, you know you've pushed it as far as you can and there will be no distortion. On the other hand, if it reads 0 VU, you've probably had a peak there somewhere that put you over the top.
A very useful feature of the 3700 has been the block error readout, which can tell the user the condition of DATs that have been recorded on several times and whether they can be re-used without risking dropouts of the signal. Public radio stations, with their penurious budget situations, find this option a necessity, since they cannot afford to buy new DAT tapes constantly, and most amateur recordists have a similar situation. The Sony also has such an error readout which can be selected on the menu. However, for some reason, the owner's manual keeps the user completely in the dark as to how to use this mode of operation. It involves punching a hole in the top portion of the wireless remote control to bring up the proper digital readout display on the deck. One would have to phone Sony for details or wait until the Dat-Heads add this arcane information to their site, where they already have an explanation of the Panasonic version of it (which is in their owner's manual).
Many professional operations have used the popular Sony consumer DAT decks due to their lower cost and easy availability. I've been using a pair of consumer D3s for years, but they spend much time in the shop and often create a cause for alarm with their squeals and burps during operation. However, there is a great deal to be said for ordinary consumers who are serious about recording, to invest in a pro DAT deck such as the R500. Considering the cost of much other pro gear it's not really that expensive for what you get, and the advantages of Super-Bit-Mapped enhanced sound, reliable operation, separate level controls, and freedom from the #%!*$#! SCMS circuit can't be beat.
© Copyright 1997 Secrets of Home Theater & High Fidelity
Return to Table of Contents for this Issue.