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Mixing Loops Live

Music Technology On Stage By Craig Anderton
Published January 2004

Mixing Loops LivePhoto: Original Kurt Kawasaki

Music technology has opened up all sorts of exciting possibilities for mixing loops with live instruments on stage, if you know how to hook everything up.

When it comes to music these days, anything goes. And that's great, because I love just about all aspects of music: playing guitar and keyboards, arranging, mixing, producing, jamming, and, of course, playing in whatever venues will put up with me. But I never thought to combine all these elements in one place at one time until, in 1998, I had the chance to see German electronic musician Dr Walker playing at the Liquid Sky club in Cologne. He was essentially using a mixing console as a musical instrument — arranging, mixing, and playing on the fly, with whatever loops, bass lines, drum parts, and synth lines made their way to an input channel. It combined DJ thinking (mixing multiple sources together), solid musicianship from his synth/MPC playing, and studio-like mixing and arranging. The proverbial light bulb went on over my head, and I realised this was the kind of playing that would be perfect for me in live performance.

That led to several gigs with Dr Walker, his group Rei$$dorf Force, and the duo Air Liquide, with me mostly playing highly processed guitar — I essentially became another loop to be mixed in and out as part of the overall texture. But this also led to my creating a solo act based on mixing loops live and, usually, playing guitar on top of various combinations of loops. The live setup went through two distinct stages; as one or the other approach might be more appropriate for what you're doing, we'll cover them both. The intended audience is what you'd find in a typical dance club, so a lot of the music is intended to flow in the way that DJs pace their sets.

The Groovebox Option

Figure 1. The first pre-laptop incarnation of my live setup used an Ensoniq ASRX to sequence loops so that they played repeatedly.Figure 1. The first pre-laptop incarnation of my live setup used an Ensoniq ASRX to sequence loops so that they played repeatedly.My first loop-based live performance setup, shown in Figure 1, was based around an Ensoniq ASRX, one of the early grooveboxes that followed in the wake of the MPC series' success. The first step was to create anywhere from eight to 16 loops intended to work well together. This was easy to do with the ASRX, as it was designed for coming up with sequences of loops and grooves.

After loading the loops, the next step was to program a very simple sequence that simply triggered the loops ad infinitum. If you pressed play, all the loops would start playing, and play all the time. But as that wouldn't make very interesting music, the final part of the process involved adding real-time control to mix the loops in and out, mute them, solo them, and in general create an arrangement that would build over a period of around 10-20 minutes, before linking into the next section.

Unfortunately, the ASRX was not really designed for real-time control, so a Peavey PC1600 fader box joined the act. This box has 16 faders that I programmed to generate MIDI Volume messages (Continuous Controller number seven), which in turn controlled the 16 MIDI channels within the ASRX. An outstanding PC1600 feature is that it has a snapshot function that allows saving particular mixes at any time, which can then be called up later in the tune. As a result, it was possible to use the PC1600 to mix the levels of all the loops.

Well, sort of possible... The ASRX was never keen on absorbing large amounts of real-time control data, and its timing would often come perilously close to collapsing — not a good thing for dance grooves. Fortunately, I had collaborated on a book with a couple of hot-shot digital designers, and they whipped up a controller thinner based on the MIDI Tools microcomputer. This thinned out the data stream enough that the ASRX's timing was relatively consistent.

Using The Hardware In Practice

The Ensoniq ASRX's ability to chain sequences makes it a viable live performance tool, although its internal memory restrictions and floppy-disk loading routine can prove tiresome for longer sets.The Ensoniq ASRX's ability to chain sequences makes it a viable live performance tool, although its internal memory restrictions and floppy-disk loading routine can prove tiresome for longer sets.Photo: Mark EwingTypically, each tune started with a few loops playing. I then used the faders to bring additional ASRX loops in and out. Once a sequence had been mixed into a fairly steady groove, the guitar came into play for overdubbing. At that time I used a Line 6 Pod, not just because I liked the sound, but because of the tap-tempo delay option, which made it easy to get the delay time right in sync with the groove. Plus, the headphone jack was great for checking that everything was tweaked up and ready to go before I stomped on the volume pedal to bring the sound into the mix. Another piece of the gear puzzle was an Electrix Warp Factory vocoder. Its main role was to gate the guitar from the ASRX drum track output. Finally, all the audio signals went into a Midiman Multimixer 6, a tiny, lightweight, six-input mixer.

The ASRX had a mode where you could assemble a playlist of sequences, so once it seemed like it was time to move on to the next sequence, I'd enable the next playlist step and, when the current sequence ended, it would switch over to the next one. Unfortunately, though, in playlist mode you were essentially locked out of messing with the sequence in any way other than what you could control externally via MIDI. But it did allow for that all-important 'never drop a beat' flow.

Another problem was that the ASRX had a 'feature' where, when a sequence repeated, the levels returned to their initial values. So I had to program fairly long sequences to keep the levels from being reset every few measures. Furthermore, because storage was on a floppy, I could get through only about 45 minutes of continuous music with what it could store. It was a major drag having to stop the music halfway through the set to load in more sounds; besides, when playing dance-oriented music at a club, there's a simple equation: dead air = dead performer.

So, I cheated by bringing a Minidisc with me! I recorded transitions onto the Minidisc, and as the first half of the set was drawing to a close, I'd fade in the Minidisc playing the transition. This involved a bit of DJ-style sleight of hand, because I had to beat match between the ASRX and the Minidisc. While the Minidisc played, I loaded up the next set from the floppy. After loading, the ASRX faded back in, the Minidisc faded back out, and I was ready to go for another 45 minutes. I also used this same transition once when I had a gear meltdown on stage from calling up the wrong presets at the wrong time on the wrong gear. Minidisc to the rescue! After I got things sorted out, the Minidisc faded out and the 'real' music returned.

Making The Most Of Minidisc

Minidisc machines can be used in a variety of ways for live performance. The first is as a kind of 'super sampler', with a huge sampling time (148 minutes in mono). No, you can't play a melody on it, but, live, I cut a lot of spoken word passages in with the beats, and the Minidisc is a perfect place to store these. Not only can you mark where pieces of audio begin, but you can also name them. This makes it easy to cue up the right sample (although in clubs with strobe lights and smoke machines, I usually need a torch to see the LCD... too bad mine's not backlit). Put the Minidisc in Pause mode, and when you want to trigger the sample, go into Play. I have some cool Malcolm X samples, excerpts from the classic comedy record How To Speak Hip, and ads for French phone sex lines that are guaranteed to make any audience sit up and take notice! Come to think of it, if Tchaikovsky had owned a Minidisc recorder, he could have just sampled the damn cannons in the 1812 overture and played them back through a PA.

You can also use a Minidisc machine to hype up your audience. I know this one is really cheating — in fact, I'm almost ashamed to mention it — but try recording some applause on your Minidisc. If the audience is, shall we say, a little short of enthusiastic, mix in some of the Minidisc applause when the first trickles of applause start. (Hey, situation comedies on TV do the same thing all the time with their laugh tracks!) Of course, mix it in very subtly or someone will catch on. But most of the time, if your music is essentially pretty good and all you need is to warm up the crowd a little bit, some canned applause can get things started. I discovered this technique when one of my loops was a piece of music that had been recorded live and included some applause. I worked for days in the studio to get rid of the applause, then finally gave up. When that section came on, everyone started clapping... and I knew I was on to something. Don't tell anyone, okay?

While we're on the subject of sampling your audience, here's a trick I learned from Frank Heiss, who was the first guy to turn me on to using Minidiscs live. He would go out into the audience and record people saying things, then later on, while he was on stage, he'd play back some of the more interesting fragments. Not only did the people being played back think this was really great, but a lot of times the comments applied to that particular venue or evening, lending a kind of real-time fun factor. Sometimes he'd blast the Minidisc output into something like a Boss phrase sampler, and twist the recordings even further — change pitch, add filtering, or whatever. For anyone who thinks audience interaction consists of going on stage and yelling 'Helloooooo [insert name of town]!', this approach might just liven things up a bit more.

The other live use I've found for Minidisc is to reinforce the tonality of the music. I have a chromatic set of low-frequency sawtooth waves, going through a low-pass filter that opens and closes very slowly to produce a meaty bass drone. Sometimes when I get going on a particular pedal point-type riff that builds on a single key, fading in a bit of the low-frequency drone adds a whole extra level of intensity. It also helps fill out the sound as you're heading for the climax.

Using A Laptop

After several gigs I wanted a more fluid setup, and briefly flirted with using two ASRX boxes, sync'ed to each other. This allowed loading sequences on one whilst playing back sequences from the other. But then I changed my setup again, for several reasons: the ASRXs were breathing their last, they were too bulky to have as carry-on luggage on transatlantic flights, and the sampling options were quite limited. So when I got a Mac Powerbook G3 (Pismo variant), the next step became clear.

I had a pretty big gig coming up at a convention 'tent party' with DJ Russ Reign, where over a thousand people were expected to show up. We decided that we would alternate, me doing 20 minutes of my solo act, then him spinning for 20 minutes, then back, and so on. I was in the process of converting my live act to run on the Pismo, and had done a successful test run during a presentation at the Macworld show, so it seemed like it was time to leave the ASRX behind once and for all. (Besides, I knew that if the whole thing blew up completely, Russ could spin and I could just jam on guitar!)

Incidentally, because I do most of my desktop work with Windows, several people have wondered why I use a Mac for live performance. Without getting dragged into a Mac versus PC debate (I use both), I believe the Mac hardware/software combination is more bulletproof live. There's something very reassuring about having the company that makes the hardware also write the software for it. Besides, I think the Powerbook design is elegant, and it's relatively easy to service. It hasn't let me down so far!

What enabled the laptop to replace the ASRX so easily was Propellerhead's Reason. I saved out my ASRX loops as WAV files, created a Reason rack with sixteen NN19 samplers, and each sampler played a loop as triggered by Reason's onboard sequencer (set to loop every eight measures or so). That took care of having 16 loops play simultaneously, and the CPU meter hardly budged at all. For newer songs, usually created in Acid or Sonar, I simply saved out the loops (again, as WAV files) for loading into Reason.

As just about any Reason parameter can be MIDI controlled, I created a PC1600 preset where each fader controlled a mixer channel's level, and each button was a solo button — perfect for hitting a breakbeat while shutting everything else up temporarily. I had also got used to the PC1600, so it made for an easy transition from my previous setup. However, I did treat myself to a PC1600X, with a bit more memory and a bigger data wheel.

Figure 2. Replacing the ASRX with an Apple Powerbook G3 reduced the size and weight of my live system, while increasing its capabilities. However, much of the original system, including the Peavey control surface, remained.Figure 2. Replacing the ASRX with an Apple Powerbook G3 reduced the size and weight of my live system, while increasing its capabilities. However, much of the original system, including the Peavey control surface, remained.As my G3 still hasn't made the transition to OS X (and probably never will — it will just get replaced by a more powerful computer with OS X), I started off using OMS with an Opcode Midisport 32 USB interface. This allowed the PC1600X to communicate with Reason over MIDI. I must say that after the difficulties of doing real-time control with the ASRX, it was a dream to be able to slam faders all night long without even the slightest timing hiccup. However, a couple of months ago I changed over to an M Audio Uno MIDI interface. It's lighter and less obtrusive than the Opcode, and fits easily into my computer bag.

For guitar, about a year ago I switched from the Pod to Roger Linn's Adrenalinn, which is tailor-made for this type of music. Being able to have exotic, tempo-sync'ed filtering effects is downright wonderful. I also use the Adrenalinn for my gigs with Rei$$dorf Force and Air Liquide. I don't even need the vocoder anymore! So now my setup has been downsized, as shown in Figure 2, although I'm still using the Multimixer 6 for mixing everything down to a stereo output capable of feeding the PA.

One really cool laptop feature is that you can practice anywhere — which is good, because I still like to feel at least a little prepared before gigs. There's something reassuring about playing a set through headphones the night, or sometimes the morning, before you need to go to the gig.

Playing It Safe

Having your act dependent on a laptop is not a secure feeling, but the good news is that there are some reliability advantages to laptops. You can carry them by hand onto a plane rather than check them in, so they needn't be subjected to the uncertainties of baggage handlers. They are also fairly immune to power problems; most laptop adaptors will run on 115V or 240V AC, and if there's a power outage, your laptop battery will take over. The adaptor/battery combo will also absorb a lot of transients and spikes that could sink other gear.

Although laptops hold up if treated well, they're inherently fragile — one solid drop, and it's over. As a result, plugging directly into a laptop's audio output jack may not be as good an option as using a USB or Firewire interface, which can connect via a reasonably long cable and be secured to a table, stand, or whatever. You can then plug all your cables into the external box; if cables get ripped out of that, you're much better off dealing with that than with a dead laptop. USB/Firewire interfaces also eliminate the need to use PCI audio cards. Expansion chassis are available to add cards to a laptop, but that's one more piece of gear, one more cable, and one more thing to go wrong.

Always be prepared; carry a copy of your operating system or software restore software, as well as all your files on CD-ROM. If your computer fails just before a gig, you may be able to find a loaner, load up your files, and carry on. That's also a good argument for using cross-platform software — you'll be covered with either Mac or Windows. If you know how to do basic computer maintenance, carry whatever tools are necessary to disassemble your computer. Once I was working in Belize when a Powerbook floppy drive got stuck, and because I had the right tool I was able to take it apart, massage the drive's worn gear, and get back into business. (This certainly beat going to the nearest Apple service centre, which was somewhere in Guatemala!)

Taking a computer on stage can be risky, but, realistically speaking, being dependent on any piece of gear has some risk — I've broken plenty of guitar strings in the middle of crucial solos, and once a keyboard froze up in Buenos Aires so badly that the reset function didn't work. (Incidentally, the solution to that was shorting out the internal battery long enough to drain the RAM contents, but not so long that the battery would explode... although come to think of it, that would have added a nice visual element!)

As long as you treat your laptop with kid gloves, and preferably have a backup available, you should be able to keep Murphy's Law at bay. Make sure your computer is well-secured, buy the best laptop case you can afford, and never leave it unattended: theft is harder to deal with than a hard drive crash.

Further Setup Tweaks

A cross-platform sequencing application such as Propellerhead Software's Reason makes its easier to get your live set playing on a loaned machine if your own laptop gives up the ghost.A cross-platform sequencing application such as Propellerhead Software's Reason makes its easier to get your live set playing on a loaned machine if your own laptop gives up the ghost.One big disadvantage of this setup compared to the one involving the ASRX is that Reason has no mode for linking songs, so you can't move seamlessly from one tune to the next. You can call up two different instances of Reason and change the focus, but it's a hassle and actually makes turntable beat-matching look simple. So I'm about to change once more, and am currently in the process of converting my live act over to Ableton Live. Thanks to Rewire, though, I don't plan to give up Reason. The net result will be even more options: the WAV loops playing back in Live, with Reason's excellent soft synths and drum machines — all subject to real-time control — looping in the background.

My only concern about the new setup is that I think I'm going to need another controller to vary effects and filter parameters; changing volume alone isn't enough any more. Yes, with the Mac I do use the mouse (more precise than a touch pad, I think) to mess with effects settings like delay feedback, wet/dry mix, filter frequency, envelope decay time, and the like; but I'd rather have real knobs, so that I can edit multiple parameters simultaneously.

If, like me, you're more of a studio creature, then it's important that your live setup is kept fairly simple. With my current system, there's virtually no setup time, and the soundcheck consists of plugging in my Sony MDREX70 headphones; making sure something happens when I click on Play and start moving faders around or play guitar; and making sure all the sounds actually come out of the PA.

I've done a lot of live performance during my life, and have been lucky enough to play with some fine musicians in a variety of contexts. But frankly, I've never had more fun playing music live than since I've started doing this act. Finally, there's a way to bring together mixing, playing guitar, arranging, and working with both MIDI and samples. Even if you don't plan to go down this road, try this way of working sometime — you just might find yourself having a whole lot of fun!