Turning Sample CDs Into Music

You've got a sampler, you've got a sample CD — but you haven't got any music yet. Craig Anderton chases down useful software that can help you bridge the gap, and passes on some hints and tips for effective sample CD use.

A lot of people still don't quite understand the concept behind sample CDs. If you can already play an instrument, why do you need other people's licks and/or sounds?

What makes sample CDs so useful is not that they can generate a canned composition 'out of the box' — although that's one attraction. More importantly, just as a great guitar sound, clever lyric, or innovative synth patch can be an inspiration, so can a sample CD. It's a short step from hearing a hot drum loop and being excited by it, to wanting to get the loop into a sampler and add sounds on top of it. In the process, you can often create a tune during the initial rush of inspiration, because at the very least, you won't need to program or record a drum part — just loop one.

Although today's samplers are widely used for assembling bits of audio into the equivalent of an audio collage, their other main function is emulative synthesis. Sample CDs can provide orchestras, drum sets, vintage synths, ethnic instruments, and other hard‑to‑record sounds. But lifting loops and sounds is only the start — the true test is how you combine these to make music.

Some sample CDs contain audio only, some are CD‑ROMs for loading sounds directly into your sampler from a CD‑ROM drive, and some are mixed‑mode. Audio versions are less expensive and easier to audition, but a CD‑ROM saves you hours — maybe even days or weeks — of programming time.

Auditioning The CD

Sample CDs are organised in different ways. Some are 'construction kits' of related, easy‑to‑loop riffs that you mix and match to create a composition; others have phrases that are not necessarily loops, but can be combined with other phrases to make ambient washes, or overlaid as 'solos' on top of more loop‑oriented material. Still others contain individual samples of specific instruments (piano, drums, gamelan, rock guitar, and so on), while many CDs combine looped riffs and the individual samples that make up the loops. This makes it easy to customise the loops by adding additional elements.

Begin by auditioning the CD to choose a collection of possible sounds, and take notes. Computer programs that play audio CDs from your CD‑ROM drive can usually build playlists of particular tracks you want to sample, so that you can audition and record them in the desired order.

Soft Options

You can, of course, record samples from sample CDs directly into your sampler, or use a compatible CD‑ROM, but another option is to transfer your desired samples to a computer for editing, then send them to the sampler. There's lots of software around to help you with this.

The standard Mac audio format is AIFF and for the PC it's WAV (however, OS/2 Warp can play AIFF files using the media player — just click on the file's icon). CDs using a native file format are easiest to use: pop 'em in the CD‑ROM drive, drag the files over, and import them into your sample editing program. To convert formats on the Mac, Sound Designer, Alchemy, WaveConvert, and BIAS Peak can all import and export WAV and AIFF files. For the PC, Sound Forge and WaveLab can import AIFF (although when exporting, change the file type to AIFF on the Mac, using ResEdit or Disktop). PC shareware translation programs include SOX: v1.0 Sound Exchange and Wave‑To for Windows.

Today's samplers are enjoying a popularity that's rivalling the synthesizer itself.

To record from audio CDs with a Mac, check out utilities such as CD Studio or SoundEdit 16 (v2), which can grab data from an audio CD and perform file conversion. For the PC, most soundcards have bundled software that can record from CDs, but beware — traditional soundcards don't record digitally from the CD, so expect some noise, distortion, and DC offset. If you're a cross‑platform kinda samplist, Disc‑to‑Disk is an audio‑grabbing utility available in both Mac and PC versions.

If your computer has a digital I/O card such as CardD Plus or MultiWav Pro, a CD player with an S/PDIF digital out can squirt audio directly into typical digital audio editing programs via such a card.

Sample Massage Therapy

Once the samples are in the computer, you can customise them before transmitting them to the sampler — you might want to EQ, truncate, or time‑compress or ‑expand to match tempo with a different loop. Digital audio editors and sample editors provide a graphic window on digital audio; most digital audio editors read WAV or AIFF as their main formats and save to and from the computer only, whereas sample editors can also communicate with samplers hooked up through SCSI or MIDI.

For the Mac, older versions of Sound Designer support older samplers, but the current version communicates only with Digidesign's own SampleCell. However, its sibling program, Turbosynth, is a cross between a sampler and synthesizer — it takes your sample and lets you twist it in fiendish ways (although you still need a way to get the sound to your sampler).

For sound editing, BIAS Peak runs in PowerPC native mode (it's also compatible with many older Macs) and is very fast. It supports SMDI (a SCSI‑based file transfer protocol) and third‑party DSP plug‑ins from Adobe Premiere, CyberSound FX, and Waves. It can also copy loop points and move them in real time — wonderful for dance mixes.

Alchemy, an industry standard for years, limits sample size to available RAM, and the DSP is primitive. However there's extensive sampler support, easy navigation, SMDI, and a unique window for adjusting the amplitude of every harmonic in a short sample.

Infinity specialises in looping just about any AIFF file you throw at it. It sounds too good to be true, but it works extremely well. Tom Erbe's Mac shareware SoundHack (commercial version also available) offers unusual DSP functions (phase vocoding, binaural filtering, ring modulation, 'spectral mutation' and so on).

The PC has lagged behind the Mac, but is catching up. SampleVision supports SDS, SMDI, Ensoniq EPS/ASR, and Akai S900/950. DSP options are extensive: distortion, flanging, delay, 4‑band parametric EQ, time compression/expansion, frequency analysis and so on.

Sound Forge, while designed for 2‑track digital audio editing, supports SDS, SMDI, and SampleCell II. It boasts very good DSP (noise reduction, vinyl restoration, reverb, and other goodies), file translation, and batch processing (with an optional plug‑in). QSound is also available as a plug‑in. WaveLab has no sampler support but is a fast audio editor with decent time compression/expansion options, pitch correction, and parametric EQ. It also builds up an audio database of samples — very convenient — and handles AIFF and WAV files interchangeably.

Even some hard disk recording programs are in on the act: Samplitude Pro and Samplitude Studio allow for SDS transfers (no SMDI, though) and offer looping, EQ, a variety of DSP functions, and spectrum analysis, amongst other features.

The shareware Wave‑To program concentrates on file‑format translation but also receives and transmits SDS, and includes tools such as cut/copy/paste, loop point adjustment, and resampling. Syntrillium Software's Cool Edit (currently shareware, but a commercial version is due soon) is a full‑function editor that's heavy on the DSP. It offers real‑time previews of many processes.

There are other possibilities you might not expect. PC programs Fast Eddie and EdDitor can handle basic WAV file processing (cut, paste, EQ, and pitch‑shifting), and on the Mac, Studio Vision Pro can convert audio into MIDI data, for editing and subsequent conversion back into audio again, while Digital Performer's hi‑fi pitch‑shifting algorithms are outstanding in their ability to minimise the artifacts often produced by this process.

Once your samples have been suitably customised, it's time to send them to the sampler.

Computer‑To‑Sampler Tough Cases

But what if you want to take one format, such as Roland, and translate it into something that your Kurzweil or Ensoniq can read? No problem (well, not much of a problem). First off, many samplers can now read more than one format anyway, but even if yours won't oblige, there are some still possible solutions.

TransferStation imports samples (8‑bit or 16‑bit, mono or stereo) into a Mac from CDs, hard disk or Syquest disk, in Akai, Roland S700‑series or audio format, saves them as AIFF or Sound Designer II files, then transmits them via SCSI to Akai S1000/2000/3000‑series devices, Emu EIV/E4K/e64/ESi32, Kurzweil K2000 or K2500, Peavey SXII and DPM‑SP, and Roland S760. You can even load 'foreign' discs into the Mac CD‑ROM drive without having them ejected.

The Sampler Pak plug‑in for Peak adds send/receive support and translation for the Ensoniq/ASR family, SMDI, and Emu's ESi32/e64/EIV samplers. However, if you just want to shoot AIFF samples, via SCSI, to an Ensoniq EPS/ASR, try epSCSI by Steve Berkley (Peak's author) or the ASR transfer utility included with Infinity. They work, but be warned: SCSI, even under the best of circumstances, can be touchy. Add a sampler to the equation, and things can get downright confusing. (For example, Sound Forge can talk to a Peavey SP with no problems, but is not compatible with the Ensoniq ASR.)

...just as a great guitar sound, clever lyric, or innovative synth patch can be an inspiration, so can a sample CD

An easier ASR solution is to save samples in the computer to disks the ASR can read, then load them in like normal instruments. Although a PC will normally not read EPS/ASR disks (let alone write files to them), Markus Jönsson's Awave (a great shareware Windows 95 program) can convert just about anything to anything, including WAV to Ensoniq family EFE format. Michael Chen's EPS Disk takes over from there: it can copy EFE files directly to ASR disks formatted using the ASR's Mac/PC‑compatible 'computer' mode. On the commercial front, Giebler Enterprise's Ensoniq Diskette Manager lets you read, write, format, and copy Ensoniq disks on your PC (a shareware reader is also available).

Someday, utilities such as these will not be necessary; many newer samplers can now read WAV and/or AIFF files directly from DOS or Mac disks, and this trend is increasing. Another option is one already embraced by Alesis — build a PCMCIA card slot into a synth, and transfer samples from your computer to a card (they bundle Sound Bridge software with their synths to do this). Unplug the card from the computer, plug it into the sampler, and load megabytes of samples in a few milliseconds.

Making The Music

A key technique in making heavily sample‑orientated music is 'pattern looping'. For the uninitiated, you map long, looped samples — for example, a 2‑measure drum pattern — into your sampler along with bass riffs, drum variations and solo samples (vocal sounds, guitar licks, FX, and so on). You then bring different loops and solo sounds in and out with the keyboard to create a finished composition.

Looping the sample itself is problematic, because even the slightest timing difference between loops will cause them to lose sync eventually. Generally, loops are triggered by a sequencer. For example, to extend a 2‑bar loop to eight bars, you simply send a new MIDI note every two bars, so that as soon as the loop stops playing, it's retriggered. Most sample CD documentation correlates sample length to tempo so that you can set the sequencer to the proper tempo.

Sometimes you'll want to use loops at a different tempo than the original recording; there are several potential ways of doing this. For example, the Def House CD‑ROM (available from East West, 0800 393027) assigns each loop so that playing G1 gives a tempo of 110bpm, A1 gives 111, and so on, in 1bpm increments up to B5 (140bpm). On the other hand, discs by E‑Lab (the X‑Static Goldmine series, for example, available from Time & Space, 01837 841100) record loops at tempos that are exactly half a step apart (112, 119, 126, and so on). Transposing the 112bpm loop up a semitone changes its tempo to 119; a whole tone takes it to 126bpm. This lets you mix and match otherwise incompatible loops, although the pitch changes a bit (you can't have everything).

Mapping samples on the keyboard is a personal matter. For 'live' mixes, I prefer to layer all the sounds across the keyboard on one channel, assign each loop to its own note, and create a mix just by playing. If you're writing at a sequencer, consider placing each loop on its own channel and track for more flexible arranging.

There's also plenty of tweaking you can do with a sampler. For really dense sounds, set up the envelope for each sample to a 'repeat' or 'finish' mode (also called 'loop in release') and set the sample to keep repeating (or copy it to itself to double the length) so that you can just touch a key and get a long, decaying phrase. Every time you send another MIDI note‑on, another layer is added to what's already playing.

Don't forget the sampler's onboard effects either. Distortion works well on drum parts, and transposing slow loops up in pitch can not only speed them up, but change the timbre. Perhaps the most valuable process is time compression and expansion. This can change loop length without changing pitch, and often also change pitch without changing length. If you want to use a 137bpm loop with a 140bpm loop, you'll really appreciate this feature. Other sampler facilities which could come in handy include the normalisation function, which can increase a signal's level; most samplers can vary the volume for individual MIDI channels.

Emulative Sampling

Sometimes you'll use your sampler to create powerful instrument sounds — a rich sampled grand piano, perhaps, or a string section. Adding realism is a whole other topic, but here are a few tips.

• Don't just change dynamics with level; also change the filter for a brighter sound with higher velocities. Modulating the sample start point can be very effective too — at low velocities, start further into the sample to bypass the attack, then program higher velocities to modulate the start point negatively, so it plays through more of the attack. Try this with any percussive instrument, including melodic ones like guitar.
• Use a volume pedal to control overall dynamics rather than trying to do it all from the keyboard.
• Use pressure to add pitch‑bend to guitar patches, or vibrato to wind patches.
• Use appropriate signal processing. Send guitar patches through a guitar amp, or at least add some overdrive or compression.
• For vibrato, learn how to shake the pitch wheel manually instead of using the canned triangle wave vibrato. Guitarists use their fingers — so can you.
• Most samplers also have synthesizer‑style processing options: filters, envelopes, LFOs, and so on. Use these to shape your sound, and don't be afraid to layer synthesized and sampled sounds — the results can be striking (to convince yourself, layer an FM harp sound with a sampled one).
• Use samples recorded with different dynamics and correlate them to velocity, preferably by crossfading between the samples so that there isn't an obvious dividing line. (Drummers take note: the Peavey SP has a special mode for triggering multiple drum hits at different velocities within a single sample, thus speeding response time and cutting down on polyphony demands.) Overlapping samples and crossfading in the overlap region can help smooth out the transition points between multi‑samples.

Getting Creative

All over the world, people who might normally have a difficult time playing music are using sample CDs and creating strikingly original forms of music, mostly centered around various mutant strains of dance music. In the process, the sampler goes from its original roots as an imitator of sounds to a creator of sounds, and even entire compositions. Today's samplers are enjoying a popularity that's rivalling the synthesizer itself, in large part because of stabilising RAM prices and the appropriation of mass‑market computer technology (including CD‑ROMs, SCSI ports and file translation programs). The tools are there, the sounds are there, and the music is there: go out and get creative!