by Jerry Vigil
It's here. Another recording format. Another replacement for the aging analog cassette. Digital Compact Cassette. There is a ton of money to be made if one can capture the current analog cassette market with a digital replacement. DAT attempted this a few years ago, but met with poor results due largely to the "copy protect" question that has now been resolved with the SCMS (Serial Copy Management System) which prevents making multiple digital copies of a digitally recorded DAT or DCC. (Even though DAT didn't live up to expectations in the consumer market, it still enjoys wide acceptance in the broadcast and recording fields.) DCC is attempting to do the same thing DAT tried, only this time, the timing is right and the DCC deck's compatibility with analog cassettes lends itself to greater consumer acceptance.
On the surface, the DCC format is very similar to DAT. They both offer high quality, digital recording to small cassettes. The decks for both formats offer the same basic features including various sub-code functions, extensive "time" displays, standard transport controls, etc.. However, as you look more closely at the two formats, the differences become more evident.
To begin with, the DCC cassette is roughly twice as large as the DAT cassette. In a technology where smaller is usually better, the larger DCC case is better from the consumer standpoint because it is identical in size to the conventional cassette. This was necessary in order to make the deck itself compatible with analog cassettes -- playback only. The cassette tape is sealed in much the same fashion as 3-1/2 inch floppy disks are, with the sliding metal door. The DCC cassette boxes are of a more modern design but still fit perfectly in a conventional cassette rack or holder, thus allowing those beloved consumers to keep using their old cassette racks.
Another major difference between the two formats is that DCC uses data compression. Data compression algorithms are used in many digital recorders to provide greater recording times on the same amount of storage space. There are several algorithms in use, some providing greater compression than others, and they all claim to provide quality, digital recording virtually identical to conventional PCM encoding or "CD quality." For the DCC to be affordable and compatible with analog cassettes, two things needed to happen: 1) the tape speed needed to remain the same at 1-7/8 ips, and 2) the heads needed to be stationary. With DAT, the tape moves much more slowly and the heads rotate, enabling more data to be applied to the same amount of tape. To compensate for this limited space for digital data, the DCC utilizes the PASC (Precision Adaptive Sub-band Coding) data compression algorithm to reduce the amount of digital information to be stored. There are some that say they can hear the difference between the DCC recording and the CD source. I couldn't. It seems the bigger question about data compression isn't one of quality, but one of concern about what happens when audio is passed through several different compression algorithms. Recently, some extensive, independent research was done on this subject. At press time, the results were not available, but we hope to have something for you soon.
Several models of DCC decks lined the shelves of audio stores across the nation as the Philips/Matsushita developed product did its best to receive a warm welcome from that large and very attractive consumer market. No doubt, some lucky audiophiles found a new DCC deck under their tree during the holidays. Under our scrutiny we found the Technics RS-DC10 DCC deck.
This particular model is priced at $999.95 and is the first DCC deck from Technics/Panasonic/Matsushita. We'll begin our tour with the front panel. At the top left are the sub-code function buttons. What DAT calls Start IDs, the DCC calls Start Markers. The AUTO button enables automatic writing of the Start Marker at the start of audio input or when the unit is put into the record mode from the record/pause mode. (During recording with digital inputs, the RS-DC10 uses the track number sub-codes of the DAT or CD to trigger automatic Start Marker writing.) The WRITE button is used to manually write the Start Marker when in the Manual mode. The RENUMBER button offers the same function as DAT's renumber function which rewinds the tape and renumbers the Start Markers beginning with number 1.
The next two buttons are where similarities with DAT end. You won't find a DAT deck with a button labeled NEXT MARKER WRITE or REVERSE MARKER WRITE. Unlike DAT cassettes, DCC tapes have two sides, side A and side B, just like their analog ancestors. These marker buttons are used to write sub-codes at the end of a side that will tell the unit to reverse sides. Reverse Markers can only be written to side A. When the Reverse Marker is used, the unit switches to side B and continues recording or playback from that point on side B. This marker would be used to continue a song on side B (if you don't mind the momentary pause while the unit switches sides), or if you simply wanted to avoid the time necessary to fast forward the tape to the beginning of side B before continuing your recording or playback.
Unlike the Reverse Marker, the Next Marker can be written to both sides. When a Next Marker is encountered on side A, the tape is fast forwarded, then playback begins on side B. When a Next Marker is encountered on side B, the unit fast forwards to the end of side B, switches to side A, then stops. These Reverse and Next Markers are functions that would have been nice to have on our old analog cassette decks, but analog cassettes don't have the luxury of a track devoted to sub-codes. That's where DCC offers a big advantage over analog cassettes.
Like DAT, the DCC records Absolute Time. When a Reverse Marker is used, Absolute Time carries over onto side B. On the other hand, when a Next Marker is used, the tape fast forwards to the start of the opposite side and Absolute Time is reset to zero.
Below these marker buttons is the MARKER ERASE button which is self explanatory. Any and all markers can be erased. Below this button is the TIMER switch which is common on just about every cassette deck and enables timer activated playback and recording. To the right of the TIMER switch is the DOLBY NR switch. This simply sets the Dolby de-coding circuitry when playing analog cassettes that have been recorded with Dolby B or C noise reduction.
The large, LED display offers a ton of information. You get tape side and direction indicators, a reverse mode indicator, Dolby NR indicators, and repeat function indicators (all tracks or just one track can be repeated). There are two large level meters (one for each channel) that display recording and playback levels. When DCC tape is used, the meter values range from -50 to zero. When analog cassettes are used, the meter range changes to -40 to +10. There's an indicator to show that a digital source has been copy protected (with SCMS). Indicators show which input is being used: Optical, Coaxial, or Analog. Indicators show sampling frequencies in use: 32kHz, 44.1kHz, or 48kHz. Analog inputs are recorded at 44.1kHz. Digital signals automatically set the sampling frequency.
Finally, there is the Time/Counter display with corresponding indicators to show Absolute Time, Remaining Time on one side of the tape, Remaining Time on the entire tape, and elapsed time of the track being played. The Counter mode can be selected when Absolute Time has not been written to a tape. (The Counter mode is the only mode available when using an analog cassette.) To the right of the Time/Counter display is the Mode display which shows the current operating mode -- STOP, PLAY, PAUSe, RECord, etc.. Regardless of which type of cassette you use, analog or DCC, the RS-DC10 kindly warns you if you've inserted the cassette the wrong way by indicating "CASS BLOCKED" on the LED display, then the cassette drawer opens for try number two.
A TEXT button above the display activates another of the special features of DCC. With the extra tracks available on DCC tapes, other digital information besides the audio and time codes can be written. This "text information" can include album title, artist name, titles of tracks, total number of tracks on a tape, total play time, and even song lyrics. And the deck will let you search tracks by title as well as track number. However, this information is only available on pre-recorded DCC tapes. You cannot record this information to a tape. But that's not to say you won't be able to, down the road, with another model.
To the right of the LED display is the input selector, record level control, and balance control. The bottom of the front panel provides the power switch, remote sensor, headphone jack, headphone level control, and the transport controls. A SIDE A/B switch does as you would expect. There are left/right SKIP buttons that operate almost like those on a DAT deck (not to be confused with DAT's Skip ID function). Pressing the Forward Skip button searches the next track on the tape. But, pressing the Reverse Skip button doesn't cue up to the beginning of the current track; it goes to the previous track. If you want to replay a track currently being played, you only need to press the PLAY button. With analog cassettes, the Skip function looks for four seconds of silence to indicate the start of a new track. You get the usual, REW, STOP, PLAY, FF, REC, and PAUSE buttons, along with the common AUTO RECORD MUTE button also found on DAT decks which is used to record four seconds of silence.
One last transport control is the APPEND button. What DAT calls the End Search function, this DCC deck calls the Append function. What DAT refers to as the End ID, the DCC calls the Use Again Marker. This marker is written automatically when a recording is stopped. Then, when the APPEND button is pressed, the unit searches for that Use Again Marker, then sets itself to the Record/Pause mode. (Use Again Markers cannot be written manually.) All of the markers mentioned above only take about three seconds to write to the tape, as compared to nine seconds for DAT IDs. The RS-DC10 does not have Skip IDs like DAT decks provide, though we did see a DCC deck at Radio Shack that did provide the Skip IDs. (This was an Optimus DTC-2000 band sold for $699.) One disappointing discovery was the unit's ability (or lack of) to closely cue up to a track. Using the deck's automatic Start Marker writing function and analog inputs, we recorded a few thirty-second tracks, then used the Pause and Skip buttons to cue up to the tracks. There is about a two-and-a-half to three second delay before the audio starts, even longer than DAT's delay. Sorry, no "instant start" here, but then again, this isn't a "pro" deck.
The RS-DC10 comes with a remote control which provides many features not accessible from the front panel. Along with all the usual transport controls and counter mode and reset buttons, you also get a numerical keypad for random access to tracks. Just one problem, as mentioned, you can't access tracks this way on tapes you've recorded yourself. The "search by number" function is only available on pre-recorded tapes that have TOC (Table Of Contents) information recorded on the tape. The remote control also offers a Music Scan mode which plays back about ten seconds of a track before moving on to the next one.
Yet another feature of the remote control is the ability to control the output level of the deck. Think about that for a moment. How many cassette or DAT decks have you seen that have their own remote volume control (not a volume control for the amp but for the deck itself)? The RS-DC10 accomplishes this remote volume control by providing "Variable Analog Outputs" on the rear panel next to the "Fixed Analog Outputs." Nice touch.
Before recording to a blank tape, the "Lead In" portion of the tape must first be written. This takes about ten seconds and, more or less, "initializes" that tape. When a new tape is inserted, simply press the RECord button. The display shows "LEAD IN" and the information is written to the tape. Thereafter, when the tape is inserted again the deck "reads" this information to ensure proper playback. The procedure for recording analog sources and digital sources is basically the same with the exception that input levels don't need to be set for digital inputs.
As mentioned, the back panel offers Variable Analog outputs as well as Fixed Analog outputs. Of course you get analog inputs as well. All are RCA phono jacks. Digital ins and outs are coaxial and optical. Reported specs for digital recording/playback include a frequency response of 10Hz to 20kHz at 44.1kHz sampling. THD is .003% or less. Dynamic range is 92dB or more, and the SN ratio is 92dB or more (record/playback, A-weighted).
Analog cassette playback specs include a frequency response of 30Hz to 16kHz for chrome tape without Dolby. This is significantly less than a good analog cassette deck provides. For example, Technics' own RS-TR555 analog cassette deck has a frequency response on chrome tape of 20Hz to 18kHz. If you've gone through the trouble and expense of recording some of your favorite CDs to chrome or even metal tape in a high-end cassette deck, you may want to play them back on that same deck. The RS-DC10 was apparently not designed to provide the playback quality of a high-end analog cassette deck. Mechanically, the RS-DC10 offers a 20-channel thin film head, a single capstan drive, and a fast-forward/rewind time of about 100 seconds for a sixty minute tape.
All things considered, the DCC format should do much better than DAT in the consumer market, but there is hardly a guarantee of that. Consumers have embraced the CD so firmly that the Sony MiniDisc might have a good chance of getting a bigger piece of the pie. Then again, there's something about the familiar look and feel of the DCC cassette that might put more consumers at ease with this digital format. And why not? Look how difficult it is for our own industry of professional audio types to let go of tape. We don't seem to mind the ones and zeros as long as they're on tape.
Look for an assault of different models in the new year, from home decks, to portables, to car units. As with the Optimus model mentioned earlier, some models will obviously offer features the others don't. From a consumer standpoint, I certainly would look for a model that will let me search tracks by number on my own recordings. The Skip ID function I can live without. I would also like to see a model that comes with a keyboard and the necessary electronics to let me record text information to the tape, be it lyrics, artist name, song title, year the song came out, whatever. And this takes us to one final thought....
What about DCC in radio production? This Test Drive is a little different in that we're checking out a piece of gear that is not designed for radio production or anything close to it. In fact, DCC may never have a place in the production room, but we did want to give you a look at this new format. Still, with a few alterations and added features, there's no reason why DCC can't end up in our studios. (For all we know, this may already be in the works.) An "instant start" feature would be a must; you've got to be able to cue things up. Another must is the ability to access tracks by number. Also, the RS-DC10 doesn't have a fast-forward "cue" or "review" mode which is handy in our business. What would really be nice is the ability to assign text information to a track -- date of production, producer's name, client name, music and sound effects used, voice-over talent names, the actual script, etc.. Now there's a handy radio production tool. One thing is certain: if DCC does capture the consumer market like the analog cassette did, your clients will eventually trash their old cassette decks for DCC. Then, when they ask for a copy of their spot on DCC, your GM will jump to sign the dotted line!
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