There are many problems inherent in taking a computer into a hazardous situation like the stage of a music venue and expecting to be able to use it to do something musically useful — or use it at all, for that matter. I'm going to focus on some of the more common difficulties that you might encounter, and draw on my own bitterly‑won experience to help you triumph over them.
For some years now, I've been using a laptop running Ableton Live software as part of a band — the sort with guitars — to provide bass, drums and what I like to call 'racket'. In the course of this endeavour, I've sustained many disasters, both personal and technical, and now I'm going to present the fruits of my misfortunes in the form of practical advice. Don't worry, I'll be sticking to the technical stuff.
I remember some years ago being told by what I can only describe as a certain 'type' of soundman (the type with a pony‑tail and a utility belt with a roll of gaffer tape, a torch and a leather pouch for his mobile phone on it) that you should always run your computer from its battery when paying live. The reasoning behind this statement was, I think, that the power supplies in most small venues are so notoriously dodgy that plugging your computer into the mains is likely to see it immediately fried by rogue power‑surges or some such.
Regardless of whether there was any truth in this theory, I dutifully did just that for several years — until the battery‑life on my laptop began to decay... In fact, I remember the occasion on which I discovered that the battery would no longer last for an entire gig quite clearly: it happened 20 minutes into a half-hour set (and less than a minute after I'd been shown a warning that only 10 minutes of battery power remained), and left me frantically scrabbling around in the dark looking for the power supply while the rest of the band tried to soldier on as best as they could without any drums (more on this in a moment).
Since then, I have plugged my laptop into the mains power at every gig and can now exclusively reveal that, after playing in many of the very worst venues in the UK (special mention to the Attic in Leicester here...), my computer has never been fried by rogue electricity. Nor have I ever experienced any problems with ground loops. That's empirical evidence, that is. Anyway, which looks better? Desperately crawling around trying to find a plug socket or your computer exploding on stage? (If you answered 'a', then you clearly have no business being in a band.)
'Real musicians' are both a curse and a blessing to the laptop musician. On the one hand, they can give you an air of live unpredictability that you will never achieve with a computer alone, and on the other, they can make the whole enterprise veer towards chaos. Which I suppose are just two sides of the same coin, really. Oh, and they're handy if you don't want to look like Kraftwerk, Orbital, etc...
The hardest thing for real musicians to grasp when playing with a laptop is that most of the time they have to follow it for their timing — especially (and, God knows, this ought to be obvious) if the laptop's doing the drums. As far as Live's concerned, this means you're going to need a count‑in, and, unless you have a very high boredom threshold, you're going to want something other than four hits of snare drum.
I always dedicate the first Scene of any song in a Live Set to the count‑in. So the Scene contains a Clip of whatever I'm using as a count‑in (drums, organ beeps, ironic cow‑bell) and the tempo of the song in the Master strip on the right‑hand side. I've managed to establish that, providing you've got them properly trained, musicians of average competence can respond to a count‑in as short as one beat in a live situation (ie. boom‑crash: start). However, it's far kinder to give them at least one whole bar (if not two) to get their heads around what's about to happen to them.
Perhaps the most important thing to bear in mind when playing a gig with real musicians is what you and they are going to do when the laptop inevitably crashes. What you need is a contingency plan. When the music stops (or carries on, leaving you with a spinning beach ball and no way to control or stop it) you're going to need a minimum of two minutes to restart the computer, re‑open Live, load the Set you were playing and get the levels back before you can start playing again. Actually, better make that three minutes. At least...
So what are your colleagues doing while all this is happening? In my band, they are playing a song we wrote called 'Crash'. 'Crash' is an improvisational piece for two guitars, odd pedal noises and whatever percussion the singer can find lying around on stage. It lasts for as long as it needs to and is usually begun by me flapping my arms a lot and then saying something like 'It's all f***ed! Play 'Crash' Arrghh!' to the guitarist, before calmly returning to my own side of the stage to sort the bloody computer out. On‑stage computer maintenance is one of my absolute least favourite things. I would say that in 100‑plus gigs we have played 'Crash' five times. That's one gig in every 20 — not a good ratio. So work out what you're going to do when it all goes tits up and try to rehearse it every now and again.
Finally, I want to tell you a cautionary tale about beer. Now you know that, as a musician, beer is your friend. It's been there for you through the good times and the bad; as a crutch, as a reward and sometimes as an analgesic. Obviously, it would be foolish to go anywhere near a stage without a pint of beer in your hand and at least another three pints inside you, but absolutely the last place beer should be is inside your computer. It is sticky and it makes computers dead. Quickly.
I know this because my last computer was a victim of beer. About three years ago, in front of lots of people who'd come to see the then‑fashionable indie band we were supporting, my laptop was suddenly wiped out by a pint of beer. I didn't even know where it'd come from to start with. We were about halfway through the first song, and all of a sudden there was a pint glass on my laptop. And beer. Lots and lots of beer. Now, there's a balcony at this club, and at first I thought somebody had thrown it, but then I realised the awful truth: it was my own pint of beer. It had fallen from the top of the PA speaker next to me, from about head height, directly on to the computer keyboard. How could beer betray me like this? We'd been through so much together! OK, it was loud — so loud that my computer screen seemed blurred from the vibrations — and the PA speaker must have juddered the pint over the edge... Finally, I was forced to admit that it hadn't been a very good idea to put a full pint of beer on the PA system and that actually it was my own fault. Not a nice feeling.
The laptop, like the band on the Titanic, carried on playing while it drowned. Completely out of control, there was nothing I could do to stop it, and as the rest of the band finished the song, I pulled the jack out of the audio output to kill the sound. After that, the screen went black and the computer switched itself off, never to switch on again. There wasn't even any point in playing 'Crash', the gig was over. A short, caustic remark into the mic and we left the stage.
So don't, and I really can't stress this enough, have beer next to, near to or directly above your computer. Put it on the floor, put it on somebody else's amplifier, but don't put it anywhere near your computer. The disaster I've just described cost me £1300 I could ill afford in destroyed computer, plus another £1300 to buy a new computer to replace it with. Cost of pint: £2603! And there wasn't even an explosion! .
One of the most embarrassing but easily remedied problems with using Ableton Live live is when Scenes hang when you try to launch them. Usually this is only for a spilt second, but if you're playing with other people it's disastrous — not least because it always seems to happen either right after the count‑in or just as you're going into a big chorus.
Live has a function to protect you from this mishap: in the Clip view, there's a button marked RAM just above the Clip Gain slider. Pressing this button means that Clip will be loaded into your computer's RAM rather than streamed from the hard disk, and will therefore play instantly when launched. Now it might seem sensible in that case to load every Clip into the RAM before beginning a set, but then your computer does need its RAM for other things... Happily, a working compromise can be reached by loading just the Clips of the first few Scenes into the RAM (I usually do the first two songs of a set, because I'm paranoid) and leaving the rest to fend for themselves. For some reason, this seems to placate Live, and it will merrily play through the rest of a set without hanging.