Digital DIY

PART 2: In this second article on digital music production, Clive Williamson looks at how musicians can use computer technology to get their work from a DAT tape to the final product — the CD.

It never ceases to amaze me that so many diverse functions can be carried out by just one computer in a studio. Inside one chameleon CPU there's the potential to edit digital sound, burn recordable CDs with PQ coding ready for glass mastering, manipulate and process digitised colour images, design covers for albums, and promote those albums with the help of business software and the Internet. The exciting fact is that the downward spiral in the cost of digital equipment places all this within reach of the average musician. So far, I've prepared four Symbiosis albums for release on CD, and hopefully, through this article, I'll be able to pass on some of what I've learned — and am still learning — to those of you who want to venture into the areas of digital mastering, burning CDRs, and desktop publishing for your own albums.

Digital Mastering

Last month, I described the digital evolution of the Symbiosis studio, and explained some ways of achieving the best recordings using MIDI and the Alesis ADAT system. The next step is to compile the mixes to make the best possible product on CD. Very early on, I decided that the ideal way of doing this was to use the Digidesign Sound Tools system and Sound Designer II software, which at that time was only available on the Apple Mac. I was already using a Mac IIcx for desktop publishing and word processing, but I had stayed with an Atari for MIDI sequencing on Notator, so adding a Sound Tools card to the Mac marked the point where it first crossed over into the recording environment. I have now upgraded to a Power Mac and Audiomedia II, but Sound Designer is still going strong, especially now that it gets support from software manufacturers other than Digidesign.

When I master a new album, I begin by assembling all the best takes from DAT tape onto a 1Gb AV hard drive, importing each one into Sound Designer through the co‑axial digital input of the Audiomedia card, and noting the peak level on the meters as I do so. I record all the tracks for the CD at 44.1kHz, so there is no need for sample rate conversion. The resulting files are saved in Sound Designer II format, which seems to have become the de facto standard for Mac digital editing. The basic task is to tidy up each track by setting the right amount of silence before the audio starts, fading each track in and out (so that the CD doesn't have any abrupt changes in noise levels between the music), then making any necessary gain alterations so that the whole album sounds balanced.

At this stage, it's sometimes useful to take the opportunity for a good listen to each track, to assess whether any EQ or further processing is necessary. There may be hum present, which can be digitally 'notched out', or the track balance might be offset. There are a number of sound processing tools in Sound Designer which can take care of these problems, but lately I've been using some of the excellent Waves plug‑ins to do these jobs — and more — because they extend the capabilities of Sound Designer and have a very good user interface too! My favourite Waves modules are the S1 Stereo Imager which can enhance and shift stereo images, the Q10 Parametric EQ (with its excellent on‑screen graphics and highly musical results), and the L1 Ultramaximizer for gain increase with minimal side‑effects using peak limiting.

Once the final processing has been applied, I delete any unwanted silence at the start of each file, but leave at least 170mS before the first audio on each track. Older CD players need about five frames to unmute after seeing the index point of a CD track, so it is safest to allow about 70mS of silence on each track before the audio, to avoid clipping the music. As the output from our mixing desk isn't completely silent, I always 'edge in' the atmosphere over the remaining 100mS before the audio, using Sound Designer's 'Fade In' option (see Figure 1). For our ambient pieces, I sometimes add an extra half‑second of silence, so that they begin after a suitable pause, but a fast start is better for up‑tempo music, or anything that is likely to be played frequently on the radio. (DJs don't like to be kept waiting to hear things!) Finally, I delete any unwanted silence at the end of the track, and use Sound Designer's 'Fade Out' to the end‑point. This prevents any abrupt changes in the low‑level atmosphere between tracks.

The Digital Balancing Act

The MasterList utility for Sound Designer is very useful for the next stage in the CD mastering process: working out any level adjustments needed to make the album easy to listen to. I import all the tracks into MasterList, then audition them in the context of the whole album, paying particular attention to the changeovers between them, and reducing the level of any tracks that seem too loud. The MasterList software only allows subtractive level changes, and chops off the quietest data to achieve the drop in volume, so if you're thinking of exporting a file from the Mac back to DAT tape, it's best not to do it at this stage. You would be losing vital details of the music!

The trick is to use MasterList in reverse. If, for example, you have tracks at ‑4dB, ‑6dB, 0dB, and ‑1dB, the ideal solution (if you think the ‑6dB track is already at — or near — peak digital level), is to add the greatest difference between tracks (ie. 6dB) to the displayed levels to obtain the actual change that needs to be made to each soundfile (+2dB, 0dB, +6dB and +5dB). In practice, it may not be possible to increase the levels by this much (and this is where your notes on the peak levels from each track come in handy!) so you may have to compromise the gain increases you apply — and actually reduce the level of track two — but the point I'm trying to make is that it is much better to increase the level of tracks, since reducing track levels also effectively reduces the maximum digital resolution. It's also important to realise that using Sound Designer's 'Change Gain' function is a better way to make reductions in level than using MasterList, because the samples are all mathematically rescaled to fit the new (smaller) dynamic range, rather than being thrown away.

Another approach would be to normalise each track, then reduce the gain of any that seem too loud, until the album is balanced, but this could mean processing the data twice for nearly every track, and I can't help feeling that it would introduce more errors. (An interesting way to allow extra gain in a track using Sound Designer alone was pointed out to me by producer and keyboard player Guy Jackson, who uses the 'Find Peak' command in percussive tracks and then reduces just that peak by a few dBs, giving more headroom in the file as a whole.)

Once the level changes have been worked out, I save the MasterList file and leave the program, then apply the 'Change Gain' command to the relevant tracks in Sound Designer. Then I can go back into MasterList, re‑open the list, and check through the comparative volumes again, this time with the gains all set to 0dB. For our first CD, Lake of Dreams, I added musically‑correct inter‑track gaps in MasterList at this stage, then played the list out to DAT and sent the tape for production in Germany. Nowadays, using our own CD‑ROM recorder with the Mac, I replicate the MasterList running order in Astarte's Toast CD‑DA software, and set the inter‑track pauses there before burning a CDR master.

The Advantages Of CDR

Symbiosis invested in a Yamaha CDE100 Recordable CD‑ROM drive a year and a half ago, and although prices have dropped since then, I'm still glad we did. Being able to burn our own CDs gives us tremendous freedom in many ways. We can create a new set of backing tracks the night before a concert, or make our own 'white labels' to give to DJs. We can back up vast quantities of data easily, and — most important of all — we can try out a new album before we send it away to be duplicated! This gives our mixes a chance to breathe. We can check them on different hi‑fi (and lo‑fi) systems, watch for level and timing problems, and easily re‑order the tracks to find the best playing sequence. Adding CDR to our digital studio has revolutionised the way we make albums, primarily because it lets us correct our mistakes before they go to the factory.

Now, when we're happy with a Symbiosis album, I make a master disc from the Toast CD‑DA software (see Figure 2 on page 146), complete with the PQ codes, and send that to the manufacturer, saving about £200 on the cost of the first CD run. A growing number of CD manufacturers are able to work directly from a Recordable disc, and although I suspect that error rates could be slightly higher when mastering this way, it certainly is a convenient — and basically cheaper — way to go. Toast CD‑DA lets you decide on the pauses and copy protection, and select whether any tracks need to be replayed with de‑emphasis. If you're registered with the right people, you can also record a barcode on the disc, and details of any ISRC codes for individual tracks, which could help make sure you receive PRS payments from airplay.

One word of warning to potential purchasers of a CD‑ROM writer: burning a CD is probably the most demanding thing your computer can do, since you need very high sustained data transfer rates through the computer and over the SCSI buss. So you need to check carefully that your computer and hard drive(s) are up to the task before investing in a CD‑ROM writer, especially if you're hoping to make discs at 4x speed!

Album Covers — The Final Frontier

Most computers that are powerful enough to do hard disk editing can easily be upgraded with the right software for DIY sleeve design. But having the right tools and knowing how to use them properly are two different things. The trick here is to know your limitations. I've been very lucky in that some of my best friends are graphic designers, so I've had the chance to learn first‑hand the techniques involved in scanning and preparing images, typography and colour printing.

A printer needs a set of four special lithographic 'films' to recreate an album's artwork in full colour, so you'll need to design your sleeve using desktop publishing software that can be used to produce these films. The current versions of Quark Xpress and Adobe Pagemaker are both suitable. These programs are able to split, or separate, the colours in your on‑screen design into their component parts in just four colours: the three secondary colours cyan (bright blue), magenta, and yellow, plus black. These 'separations' — known as CMYK, or 4‑colour separations — are printed onto sheets of photographic film like giant negatives, and sent to the printers to make the printing plates (see Figure 3, above).

Artwork and photos have to be digitised to be included in your design. This can be done either by professionally scanning at an image bureau, or more economically with the Kodak PhotoCD system. Ideally the images should be retouched and adjusted using a trained eye and Adobe's excellent Photoshop software (available for Mac or PC) to optimise the final print quality. Another important factor is typography: you need to install typefaces on your computer to use in the designs, and these sometimes need fine‑tuning by hand to get the best letter‑spacing. In addition to the colour elements of the album cover, extra films are usually required for the black and white print inside the booklet, and for one or two colours to be screen‑printed onto the CD itself, so the whole package is quite complex, and certainly isn't something to undertake lightly. Once you get the hang of it, though, it's exciting and satisfying.

I could fill this entire issue with details about the printing process, but they won't let me, so try to get hold of the booklet that comes with Pagemaker (the Print Publishing Guide) which gives a good overview of the process. The most important thing to remember about an album cover is that often it is the first way people encounter your work. After all the effort that goes into making the music, it's vital that a record should look as good as it sounds, so budget for a good sleeve right from the start.

Computers And Your Business

If you still have any time or energy left after making the music, burning the CD and maybe even designing the cover, remember that the computer sitting in your studio can also be a great help with your business activities. In the Symbiosis studio, our Mac runs Microsoft's Word 6 for letter writing and contracts, Claris Filemaker Pro for invoicing and a customer database, and all the DTP software is also used to design fliers and catalogues. A very useful addition to the system has been a Mac‑compatible modem, which lets us fax directly from the computer, and has opened up the possibilities of electronic mail and marketing via the Internet. We're planning a web site to let people find out more about the group and our albums, and even to hear extracts of our music. Ideas, hardware and software change all the time: we were excited by the possibilities of releasing CDs with a data track, combining graphics, photos, text and videos with our music using Macromedia's Director software. However, I now think that a web site would offer greater possibilities for interaction, so that's our preferred multimedia route for now.

Conclusions

Technology today puts musicians in a unique dilemma: we have to juggle our time making music with the time needed to acquire new computing and recording skills and to promote our work. If we can learn to balance all three elements, then computers really could help us to open a lot of doors. We also need to take time to make the right choices about when (and if) we should buy attractive new hi‑tech equipment, and above all, try not to get upset with equipment that doesn't work as it should — nothing kills the muse quite like Techno‑Rage!

Thanks to Adobe Systems, Leading EdgePR, Macromedia and Sound Technology for their help in preparing these articles, and special thanks to Della Drees, Micheline Mannion, and Brian Whitehead for their invaluable design advice and assistance.