You are here

Philips DCC730

Digital Recorder By Paul White
Published July 1995

Most home recordists would love to own a stereo digital recorder, but the relatively high price of DAT and MiniDisc has kept this desire a pipe dream — until now. Paul White tries out the very attractively priced Philips DCC730 digital recorder and discovers what could become a new standard in affordable digital mastering.

For more than a decade, the audio industry has been trying to convince the buying public to forsake their analogue cassettes in favour of digital recording; first in the form of Sony's PCM F1 system, which worked with a suitable Betamax video recorder, then with DAT, and most recently with Philips' DCC and Sony's MiniDisc systems. However, the greater listening public have largely ignored these advances — indeed, they've demonstrated their seeming disregard for audio perfection by making TDK's budget 'D' ferric cassettes a top seller, while sales of the technically superior Type II (chrome) and metal cassettes lag behind by a significant margin. In a logical world, you might expect that a failed professional recording format might eventually filter down to the consumer market, but what's actually happened is that the pro and semi‑pro audio industries have come to rely almost entirely on DAT, a failed consumer format, for stereo mastering and archiving.

Great value though DAT is, the initial prevalence of cheap DAT machines has made people reluctant to pay upwards of £1,000 for a professional model (even though a technically inferior analogue 2‑track will cost at least this much). And now that the supply of very cheap DAT machines is drying up, a great many home studio owners are wondering which way to turn for mastering. Furthermore, certain very cheap DAT machines have gained reputations for unreliability.

Just when we had almost given up the Digital Compact Cassette (DCC) for dead, it seems now almost certain to become a significant player in the private studio market. Two years ago DCC machines cost about the same as budget DAT machines, and because they utilise data compression (which, on paper at least, results in a slight loss of fidelity), it seemed that we were being asked to pay too much money for a product with no obvious advantages over DAT. To compound the problem, Sony's MiniDisc system came on the scene at around the same time as DCC with the inevitable result that the mass public, keen to avoiding choosing the audio equivalent of a Betamax video, bought neither — introductory sales were far lower than anticipated. Sony's MD system wins out in the cuteness stakes because it has the instant track access advantage of conventional CD, and the less technically aware members of the public may also instinctively feel that a disc offers better sound quality than any form of tape. However, DCC machines tend to fare slightly better in comparative listening tests, presumably due to the differences in the data compression systems used, and though DCC doesn't offer instant track access, DCC machines can replay conventional analogue audio cassettes as well as recording and playing DCC digital cassettes.

It would seem that DCC is now the perfect answer for those looking for a low cost means of recording high quality stereo digital masters.

The third generation of technically improved DCC recorders has just been launched at an aggressively low price point — £249 inc VAT — which is little more than half that of MiniDisc and well under half that of most budget DAT machines. To put things in perspective, you can now buy a DCC recorder for around twice the price of a typical hi‑fi cassette deck; the sound quality is so close to that of DAT that few people will be able to tell the difference, even on very demanding material; and because the digital I/O ports on DCC machines are S/PDIF compatible, data can be copied between DCC and DAT entirely in the digital domain. It would seem then that DCC is now the perfect answer for those looking for a low cost means of recording high quality stereo digital masters. Unfortunately, the SCMS anti‑piracy copy management system is fitted which, as always, inconveniences the legitimate user more than it does the determined copyright pirate.

For those unfamiliar with SCMS, this system only applies to recordings made via the digital input. You can make unlimited direct copies from a digital master (such as a CD or DAT), but no further digital copy can be made from your first generation copies. This causes problem when you try to clone your own backup tapes in the digital domain, though unlimited recordings via the analogue inputs are permitted.

DCC730 Features

Philips' DCC730 is a hi‑fi format machine and is the same size as a typical 'separates' cassette deck. The analogue inputs and outputs are on unbalanced phonos, just as you'd expect on a piece of hi‑fi gear, but you also get S/PDIF compatible digital ins and outs on phono connectors, plus an optical S/PDIF input. A wireless, infra‑red, remote control is supplied with the machine along with a full set of cables and a blank DCC tape to get you going.

As with a DAT machine or CD player, the media is loaded via a motorised drawer controlled by the Open/Close button, and if you're thinking the front panel looks very simple, that's because a lot of the functions normally served by switches have been moved into software. The display below the tape drawer includes the record level indicators, track information, and a text area where up to 12 characters can be displayed. You can enter your own track titles (up to 40 characters), and these will scroll if they exceed 12 characters in length. Pre‑recorded DCC cassettes may also include additional text information, including the artiste's name and even scrolling lyrics — but no bouncing ball! Having said that, the current pre‑recorded DCC catalogue probably contains fewer titles than you have in your own album collection.

A headphone output is provided to the right of the machine and there's also a stereo jack input for a suitable stereo microphone (200—2,000 Ohm impedance). Unlike a standard cassette machine, the level metering display doesn't use conventional bargraph meters and is only present for 10 seconds following an adjustment of the recording level — unless you change the default setting, in which case you can look at it for as long as you like. The level information is presented as a peak level value (updated every second or so), with the headroom in dBs, and an over indicator. Any record level changes are made using up/down buttons, not knobs, from which I assume that the designers imagine most users will be digitally copying their CDs, where gain control and metering is less important than in studio applications. Even when the metering isn't on the screen, the 'Over' indicator still comes on if you put in too high a signal, but I'd still feel more comfortable with bargraph meters.

...the DCC730 is a superb budget mastering machine marred only by the lack of more conventional metering.

When you're recording in digital mode, there's no metering at all. I know that you don't need to check the level of a digital input, but metering still provides valuable confirmation that the signal is getting through OK. In playback mode, the default setting provides tape position information rather than metering, but you can change this if you prefer so that the metering information is always on view.

Because the consumer is likely to have a number of potential sources from which to record, including CDs and tuners, the DCC730 allows the user to programme preset record levels relating to four different sources; the idea being that, once set, you don't have to bother about them again. In theory, this means you could use the level setting to calibrate the DCC input to your mixer's output, allowing you to use your desk's meters to obtain a more accurate picture of what's going to tape. The CD input preset may also be set to digital, optical, or analogue. Personally, I prefer physical switches, but I concede that being able to store optimum record levels for up to four sources is a good idea. Note however that if a mic is plugged in, this overrides whatever other input source may have been selected.

Like DAT, you can do more than simply record and replay audio signals — you can also store track IDs, allowing you to search to any particular song on an album, and if you have the inclination, you can also name your tracks. The deck itself has a reverse operation, so you don't need to turn the tape over at the end of the first side. You can also decide what happens at the end of the last track — you can either continue from the same physical location on Side B, or have the machine wind to the start of Side B before continuing. If the tape approaches the end of Side A whilst you are recording, the machine goes directly into reverse mode to minimise any lost information, but there doesn't seem to be any kind of buffering system to close the gap. What this means is that you have to think in terms of conventional cassettes, where you have two discrete 'sides', rather than CD and MiniDisc where everything is continuous from beginning to end.

When you first make a recording (you have a choice of 32, 44.1, or 48kHz via digital and optical connections; 44.1kHz only for analogue line inputs), the machine writes a leader to the start of Side A, after which the counter starts at zero indicating that recording can start. If you're recording the tape in sections, the Append function lets you join up with the end of the last recorded section, but if you want to make your own decision as to whereabouts to start recording, the Pause/Record function will let you do just that. It is important not to leave any unrecorded tape between tracks though, otherwise the automatic track numbering won't work. Similarly, you can renumber tracks after recording, just as you can on a DAT machine, but again there must be no unrecorded sections between tracks, otherwise the subcode will have discontinuities which will prevent the numbering process from working. It is good policy to leave the DCC machine recording for a few seconds once you've finished mastering a mix, simply so that the subcode extends beyond the end of your song.

Sonic Impressions

To confirm that the DCC730 was compatible with DAT, I digitally cloned a tape I'd made in the studio and had no trouble with this procedure at all. When the two recordings were compared (by switching from the original to the copy during replay), a difference in sound was just evident, but it was subjectively no greater than the difference between one make of DAT machine and another. On very ambient, airy music, I felt that something subliminal might be being suppressed very slightly, but again the effect was so subtle that it could easily have been the result of other factors — such as the difference in tone between the converters in the DAT machine and those in the DCC machine. Test recordings made via the analogue inputs also showed the recording quality to be truly excellent.

The fast‑wind time was surprisingly fast, and though DAT tends to spoil you in this respect, the DCC730 spools through a minute of audio in just a second or two. In fact, if it isn't near a Start or Stop ID, its top speed actually breaks the one minute of tape per second barrier. Having the ability to locate song starts, just as you do with DAT and CD, is also very useful, and on the whole I found the machine pretty intuitive to use.

Blank media costs are respectable: a 75 minute DCC tape (enough for an entire 73 min CD) costs £6.49 inc VAT and £6.99 for a full 1.5 hours (90 mins).

When used for playing back pre‑recorded compact cassettes, the choice of Dolby B or Dolby C ensures reasonable compatibility with your existing tapes. But as pointed out in the manual, while DCC tapes are unlikely to dirty your heads, analogue tapes could well leave oxide behind, and in the case of DCC machines, you need a special head‑cleaning tape. As an analogue tape player, the DCC730 can only be described as adequate, and in a digital mastering context I think I'd be inclined to ban analogue tapes from the machine altogether.

Verdict

At its current RRP of £249 inc VAT, plus free blank tape and infra‑red remote control, the DCC730 is a superb budget mastering machine marred only by the lack of more conventional metering. Even so, thanks to 18‑bit resolution, you have enough dynamic range (92dB at 1kHz) to leave a generous amount of headroom, so you can get by pretty well without precise metering. Signal‑to‑noise ratios are quoted as 105dB on playback (A‑weighted, 1kHz) and 100dB for analogue input recording. The fast‑wind time is surprisingly fleet for a non‑rotary head machine, and to all intents and purposes the recording quality is indistinguishable from DAT or CD. Indeed, if you're recording using the analogue input, you'll actually get a little more dynamic range than you would with a DAT machine.

Also reassuring is the fact that the digital I/Os seem happy enough talking to DAT machines (at 44.1kHz), and that bodes well for those who want to download their finished mixes into digital editing systems or make DAT clones. In fact, you have the advantage that the sample rate of DCC conforms to the pro 44.1kHz, rather than the '48kHz only' standard adopted by most budget DAT recorders.

I still think that DCC is about as likely to make it as a consumer format as you are to find crop circles in your muesli tomorrow morning, but for anyone looking for an affordable, high quality digital mastering system that maintains a high degree of compatibility with existing equipment, I have no hesitation in saying that the Philips DCC730 represents an excellent way of spending £250. And if you want a portable DCC machine that's about the size of a Walkman and includes mic inputs, a little birdie (well, a press release actually!) tells me that something conforming to that description will soon be available for exactly the same price. (Expect a review in SOS in the near future.) The way DAT machines keep going up in price, DCC could well become the home recording digital standard for the latter half of this decade.

The Dcc Format

DCC (short for Digital Compact Cassette) is a digital tape recording system invented by the Dutch consumer electronics giant Philips. DCC uses a stationary (S)DAT record/play head, as opposed to a rotating, video‑style head found on (R)DAT machines. In order to get enough data onto a tape running at the same 1.75 ips (inches per second) as a standard audio cassette, DCC records the data as several parallel stripes, much like the tracks on an analogue multitrack recorder. This requires a very special type of tape head, and the technical problems involved in manufacturing this head in quantity were partly responsible for delaying the commercial launch of DCC, several years ago. To maintain backwards compatibility with already recorded analogue cassettes, DCC machines incorporate an analogue playback head and Dolby B/C decoding, but it is not possible to record analogue compact cassettes in a DCC machine.

Even with the technology behind DCC cassettes and heads, there still isn't sufficient capacity to record 16‑bit audio in the same linear format as used by DAT and CDs, so data compression is used to reduce the amount of data needed to represent the audio signal. The compression system used is known as PASC, and works by mimicking the way the human hearing system perceives sound. Essentially, the human hearing system can't hear everything at once because some sounds are always masked by others. So if a sound is masked, why bother recording and reproducing it at all? By constantly examining the spectral content of the music or sound being recorded, PASC identifies those elements which have been rendered inaudible by masking, then systematically discards the irrelevant information prior to recording, achieving something like a four‑fold improvement in the amount of data that can be accommodated.

The latest generation of DCC machines (like the DCC730 under review) start out by sampling the incoming signal not at 16‑bit but at 18‑bit resolution, which gives a potential improvement in both dynamic range and residual noise of around 12dB. Of course, if you're recording from a 16‑bit digital source, there will be no increase in resolution. After data reduction, you still keep the resolution and dynamic range, and though some purists claim to hear a minimal loss of stereo integrity or 'space' when listening to well‑recorded classical music, the real‑life situation is that on the vast majority of pop music, DCC sounds just the same as DAT.

DCC tapes are physically the same size as analogue compact cassettes (also a Philips invention), but are fully enclosed like video tapes and come in a special slide‑out library case. The tape formulation is different to that of analogue tape, which is one of the reasons why you can't make digital recordings on ordinary cassettes. The other reason is that digital recording doesn't tolerate dust very well, so a fully enclosed tape package is essential.

What About Alternatives?

Here are a few alternatives to a DCC recorder that you might want to consider:

  • Pro Cassette Recorder
    A high quality, professional stereo cassette deck, such as a Denon DN720R Pro, will set you back £429 inc VAT, and still not match DCC for audio quality.
  • DAT Recorder
    You'll pay well over £600 for a new DAT machine (although some portables are cheaper). A Sony DTC60ES will set you back £599 inc VAT, for example. But frankly, you'd be hard‑pushed to find even a used DAT machine for the DCC's asking price.
  • MiniDisc Recorder
    Sony's alternative format to DCC also uses data compression, but the recording model is double the price of the DCC730 (around £500) and only offers digital I/O via its optical connector. MiniDisc is arguably cuter and offers the benefits of random access, instead of shuttling tape, but at a price.

In truth, there are currently no real alternatives to DCC which offer high quality digital audio for under £250 inc VAT.

Pros

  • Excellent sound quality.
  • Very attractive price.
  • Easy to use.
  • Also plays standard audio cassettes.
  • Infra‑red remote control included.

Cons

  • No bargraph metering system.
  • SCMS copy‑protection.

Summary

At this price, DCC is currently the only low cost option for high quality, stereo digital mastering. A real bargain.