by Jerry Vigil
"It's a Sony." Now that's a slogan from a strong advertising campaign. It left consumers with the impression that if you had a Sony, you had a pretty good piece of audio or video gear. When it comes to DAT machines, the same pretty much holds true. And why not? Sony invented DAT. This month's Test Drive takes a look at Sony's new PCM-2700, a moderately priced, professional DAT recorder/player with a handful of features.
For the $2,900 price tag, the PCM-2700 brings to the studio a unit with the ability to record and playback at three different sampling frequencies: 48kHz, 44.1kHz, and 32kHz, of which the latter provides LONG PLAY mode. Frequency response of the unit in the LONG PLAY mode is 20-14.5kHz, adequate for broadcast applications. But the big advantage of the LONG PLAY mode is the four hours of recording time you get on one 120-minute tape. Four hours! Digital recording! No hiss! You can store over two hundred sixty second spots on one of these tapes. You can store almost over four hundred thirty seconds promos on one tape. But there's still one little glitch that needs to be addressed if manufacturers are going to please us prodo folks: we need DAT machines that can number programs beyond 99! (There is a way to number and access programs beyond 99 as discussed in Tips & Techniques, October '91 RAP. Basically, you have more than one set of 99 programs on one DAT.)
There are other "broadcast" advantages of the LONG PLAY mode aside from added storage. If your station airs syndicated programs that arrive on vinyl or reel-to-reel, up to a four hour show can be transferred to one DAT, which would eliminate having to mess with switching reels or disks live, on the air. Commercials and promos could also be transferred with the pre-recorded program to DAT so that even less "live" action is needed during broadcast. Ob-viously, if you're transferring music to DAT, one 4-hour tape can hold a lot of music. (Note also that a lot of DAT machines can playback a 32kHz recording, but they can't record in the 32kHz, "Long Play" mode.)
Next on the list of attractive features is the 4-head design of the PCM-2700. Most DAT machines are of 2-head design -- one record/playback head for each channel. The PCM-2700 adds an additional playback head for each channel which provides monitoring of the playback signal during recording. This is important in the production studio if you're mixing to DAT and have any processing (like a compressor/limiter) in between the console and the DAT. Monitoring playback during recording ensures you that you're recording what you think you are. This 4-head design is similar to the 3-head format of a standard 2-track reel-to-reel which brings to mind the question of "tape echo." Yes, you can get tape echo from this unit, but it's not quite the same as what you get when you crank up the playback of a reel-to-reel during recording. To begin with, in the Standard Play mode (48 or 44.1kHz), the delay is very short -- approximately 120ms. That translates to about eight repeats per second. In the Long Play mode, you get about four repeats per second with the delay at about 240ms. In comparison, the "tape echo" delay of the PCM-2700 in Long Play mode is still not as long as the delay of an analog reel running at 7.5 ips.
The other interesting feature of DAT "tape echo" is that you're feeding an extremely clean, digitally recorded signal back into the input. So, instead of tape echo that slowly drops in level as the noise level rises, you get consistent, clean repeats of the input, and it goes on and on and on. The only way to get the "fade away" effect of tape echo is to actually drop the level of feedback at the console. The effect is really no more interesting that analog tape echo, but, nevertheless, you can get it. Most important is the ability to monitor playback while recording.
Another nice feature of the PCM-2700 is the built-in date function. If you keep track of when spots and promos are mastered to DAT, you'll appreciate the unit's ability to automatically "stamp" each recording with the current date and time from an internal clock that is set upon installation. (A battery backup retains clock/date settings for about five years even when the unit is shut off.)
Most of the other features are either technical or minor in nature, and we'll cover those as we tour our front and rear panels. Beginning on the left side of the front panel, beneath the power ON/OFF switch, is the remote Sensor. The PCM-2700 comes with a wireless remote, and an optional wired remote is available. One of the switches below the sensor selects wired or wireless remote control. Virtually all the buttons on the front panel are on the wireless remote control. Also, the wireless control adds a "music scan" function. The optional, wired remote (RMD7100) only has tape transport controls and an INPUT MONITOR button.
Under the remote wired/wireless switch is the INPUT SELECTOR switch. When on "Digital," the unit will record whatever is connected to the digital input on the rear panel. When the analog inputs are used, the switch is moved to "Analog" and selects sampling frequencies of 44.1kHz or 48kHz. (32kHz sampling frequency is selected by engaging the Long Play mode.)
The cassette compartment is a "door" type much like those on standard cassette decks, as opposed to the "tray" or "drawer" types of compartments found on many other units. Inserting the cassette feels like a much more delicate procedure on the PCM-2700 than simply setting a cassette in a tray or drawer and hitting the CLOSE button. When closed, a light illuminates the cassette and label for easy tape identification.
At the bottom of the panel are the usual DAT transport and record controls: STOP, PLAY, PAUSE, REWIND, FAST FORWARD, PREVIOUS, NEXT, RECORD, and RECORD MUTE. Above these buttons are the controls for the subcodes and the tape counter. You get the usual AUTO, WRITE, RENNUMBER, and ERASE functions for the Start ID, as well as the usual Skip ID and End ID Write and Erase functions. (The End ID function is not found on all DAT machines and basically places a code that can be used to designate the last point at which the tape was recorded. This is a necessity when re-using tapes that have already been recorded on.)
The large knob at the bottom right of the panel is the input level control and is used only when the analog inputs are used. Next to it is a headphone jack and headphone level control.
At the right of the panel is a numeric keypad used for selecting programs for play. The keypad is also used for entering data when using the unit's search functions. Other buttons around the keypad access the internal clock, Fade-in/Fade-out, Skip Play, Copy Prohibit, Margin, Time Search, Long Play Mode, Input Monitor, and Repeat functions. Pressing any of these buttons usually results in an indication of one sort or another on the large display window.
The display is loaded with information. A bright orange "Long Play" light illuminates to inform you that you're in the 32kHz LP mode, selected by pressing the LONG/STANDARD RECORD MODE button just above the display. (The 32kHz sampling frequency is automatically set when this button is pressed, and the tape speed drops to one-half normal speed.)
An "Emphasis" indicator lights when a tape recorded with emphasis is played back, or when the signal being recording at the digital input has emphasis applied to it. In other words, only the de-emphasis circuit is in the unit. You can play or record an emphasized signal, but you can't add emphasis to a recording. (If you're unfamiliar with "emphasis" in digital recording, it is basically a function that reduces noise by boosting highs during recording then "de-emphasizing" or cutting the highs on playback.)
A "Copy Prohibit" indicator illuminates when recording a digital signal that contains the copy protect code. The Copy Prohibit code can be written to tape while recording by pressing the COPY PROHIBIT button.
The time display can be switched by pressing the COUNTER MODE button to show "Absolute Time," "Remaining Time" on the tape, "Program Time," or "Counter" time. Absolute time is recorded permanently on the tape and can be used with the Time Search function to locate a specific tape time, like 1:32:10. When the Time Search function is used, the "Time Search" indicator lights on the display, and the search time is entered using the numeric keypad. When in the Counter mode, the COUNTER RESET and MEMORY buttons can be used to set a "zero" point on the tape. When Memory is enabled, the tape transport controls can be used to search the zero point and begin play much like the "search zero" function of a reel-to-reel.
The Time Display also serves as the Date Display. Pressing the PRESENT button displays the current date. Pressing it again displays the current time. Pressing the RECORDED button displays the date the current program was recorded. Pressing it again displays the time it was recorded. As you scroll through the different Date/Time displays, indicators light up on the display to show you what you're looking at.
Other indicators on the display include TOC which lights up when a pre-recorded DAT tape with a Table Of Contents is used. You get a "Caution" light to warn of condensation in the unit. A "Coaxial Digital In" indicator lights when the input selector is set to Digital. "Skip," "Start," and "End ID" indicators light when writing, erasing, or detecting the ID's. You get a constant display of the current sampling frequency. Of course, you have your usual Program Number display and AMS (Automatic Music Search) number display.
The "Music Scan" indicator lights when the unit is in the scan mode. How long the unit will play the beginning of a program before the next Start ID is searched can be easily adjusted to as much as fifteen seconds. Pressing the REPEAT button lights the "Repeat 1" indicator, and the unit will play the selected program sixteen times before stopping. Pressing the REPEAT button again lights the "Repeat All" indicator, and the entire tape will play sixteen times.
The "Fade" indicator lights when the FADE button is pressed. This indicator also displays the present fade setting which can be adjusted anywhere between .2 seconds to 15 seconds. If the unit is in the Pause/Play mode, pressing the FADE button will engage the Play mode and fade the audio up to full within the preset fade time. Pressing the FADE button again will fade the music out and return the unit to the Pause/Play mode. When in Record/Pause mode, pressing FADE begins recording with the designated fade-in. Pressing FADE again begins the fade-out and return to Record/Pause. Many units offer the Fade-in/Fade-out function, but not all of them let you adjust the fade time. Because the fade time is so easy to adjust -- press FADE in the Stop mode, then press the FF and REW buttons -- the Fade function of the PCM-2700 becomes a handy tool for a lot of production tasks. Sure, you can fade things from the console, but this fader is digital, and perfect. If you master to DAT, then dub to cart, pressing FADE at the end of the spot as you dub eliminates a lot of noise that often ends up after a spot on a master -- tape hiss, clicks and pops, and other noises.
The "Margin" indicator on the display is a welcome feature. When setting levels, this indicator shows how much room, in dB's, is available between the last, highest peak level and zero dB. If zero dB is reached, the "Margin" indicator flashes to warn that you're overloading the input on some peaks. The display retains the last recorded peak until a higher one occurs, or the display can be reset with the MARGIN RESET button.
The two Peak Level Meters at the bottom of the display window show input levels and playback levels. This is switchable with the INPUT MONITOR button. The meters can also be switched to the Frequency Map mode by pressing the COUNTER MODE button and "4" simultaneously. In this mode, the meters become a "map" indicating the sampling frequencies used to record the different portions of the tape. The top of the tape begins at the far left of the meters, and the end of the tape is at the far right. If the 32kHz sampling rate is used, only the top bar will be lit. If the 48kHz rate is used, only the bottom bar is lit. If the 44.1kHz rate is used, both bars will light. To test a tape for various sampling frequencies, simply insert the cassette and fast forward it to the end. The unit reads the tape as it fast forwards and displays the sampling frequencies on the tape. This feature might best serve someone preparing a DAT for CD pressing. With this function they could quickly ensure that the entire tape is recorded at 44.1kHz.
The "Rehearsal" indicator lights up when the Rehearsal Mode on the PCM-2700 is engaged. This mode enables easy adjustment of the location of the Start, Skip, and End ID's. As you adjust the ID's, the display shows, to the tenth of a second, how far you have adjusted the ID in either direction.
The back panel of the PCM-2700 offers balanced XLR inputs and outputs (yes, your engineer will like this). RCA phono jacks are used for the digital in and out. A 37-pin connector is used for the optional wired remote control. Finally, analog record and playback master levels can be set from the rear panel. Out of the box, they are preset to +4dB and can be adjusted to a maximum level of +24dB. This easily accommodates installation in a variety of studio configurations.
Other specs include 16-bit linear/12-bit non-linear quantization. Rise time (the time it takes the machine to begin playback or record) is one second or less from Pause to Play, and two seconds or less from Stop to Play. Search speed is 150 times normal playback speed, and the cue/review speed is ±3 and ±8 times normal playback speed. It is at three times for the first four seconds, then automatically shifts to eight times normal playback speed after four seconds. The S/N ratio is greater than 90dB. THD is less than 0.05% in the Standard Play mode and less than 1.0% in the Long Play Mode. As mentioned, the unit comes with the wireless remote control. Also included are rack mount adapters.
When looking for a DAT machine for your production room, there are several things to consider. As with any piece of gear, the more major features it has, the more it will cost; and with professional, digital recording gear, the available features are often times features the radio production studio will never or rarely need. Why pay for extras you don't need? One feature found on many high dollars units is SMPTE time code capabilities. If you don't use SMPTE, don't pay for it. Other machines run up their cost by providing circuitry capable of delivering dynamic ranges pushing 100dB and THD of less than .001%. There are different types of A/D and D/A converters in use. Some are more expensive than others. Consider your needs; for radio production, this "near perfect" quality recording and reproduction is not necessary. Some units offer mike preamps and connectors (particularly on portable units). If you're not going to be plugging mikes into the unit, it's not for you. When shopping for a DAT unit, consider what features you would like, then look for units that offer those features.
In the same sense, be careful not to get less than you want. Perhaps most noteworthy when shopping for a DAT for your studio is whether it is a "pro" deck or a "consumer" deck. Consumer decks are less expensive and can be bought at your local stereo/hi-fi store, but you may need some "pro" support down the line. "Pro" dealers and manufacturers are more apt to take care of you when you need them. When you need repair work done, Joe Blow's Stereo Store might put your DAT deck on the bottom of a stack of cassette decks and car stereos and ask you to come back in a few weeks. When buying "consumer" or "semi-pro" gear, always consider support after the sale as one of the features.
The PCM-2700 has features that will appeal to the radio producer, but it doesn't overload you with major features you'll never use. It doesn't offer SMPTE time code functions (Saving $$$). It doesn't come with the ability to add an extensive number of options you'll never use (Saving $$$). There are no mike inputs (Saving $$$). On the other hand, you get the LP mode, 4-head configuration, and XLR ins and outs. It's rack mountable and priced such that you won't be making a major purchase to add DAT to your production room. All this, and on a deck with a respected name in professional recording.