Auto-tune has been around for a while now, and has been a useful tool in many producers’ arsenals since the 1990s. But thanks to people like Cher, and latterly T-Pain, it’s been getting a reputation as a plugin that’s for commercial RnB and dancehall only. It certainly sounds pretty distinctive when pushed hard like that – but it can also gently iron out imperfections, and even be a useful tool for creative sound design. So let’s take another look at this most maligned of processes…
Auto-tune is something that comes in many flavours – far from the original boxes of the old days, you’ll now more likely find a plugin in your DAW called something like ‘Pitch Correction’, while the bigger studios often use the expensive but remarkable Melodyne.
The first thing to note is that the T-Pain effect (as it will probably be forever known) is actually a very extreme use of auto-tune. It doesn’t need to be used like this, and in fact most big records these days will have some pitch correction in there somewhere – it will just be used quite subtly! It’s a shame that so many people associate the two so strongly; while doing a mixdown for a local producer recently I told him I was going to put some pitch correction on his singer’s vocal, and he was very resistant to the idea. Until he saw that when used normally, it doesn’t need to sound like chart pop track.
So let’s say you’ve got a vocal that needs some correcting. What do you do? First, load your plugin. Then you’ll need to set the key – you can use various major or minor keys, and these will let the plugin know which notes it can push the vocal onto, and which it can’t (because they’re not used in that particular key). So set this to the key that your track is in. If your singer has done a lot of adlibs or general soloing, it might be easier to just leave it on ‘chromatic’ mode – so that the plugin will just push it to the nearest note, regardless of what key the track might be in.
Alternatively, there are options to ‘bypass’ certain notes in the scale, so that if the vocal is slightly off with particular notes, the plugin will just leave them. This is particularly useful if you’ve got a vocal with some bluesy slides between certain notes (often the minor and major 3rd), which you want to leave intact. Bypass these and the plugin will only quantise the things you want it to.
Next, and quite importantly, is the ‘response time’ function. This is the real T-Pain setting. Set it to 0ms and the pitch will jump instantly from one note to the next, in a very artificial manner. Instant RnB vocals! Set it to something much longer, like 800ms, and you’ll find that the plugin takes a long time to slide to the correct pitch – probably too long in fact, as the singer will have moved onto the next note. So you need this to be slow enough to sound natural, but quick enough to keep up with the movement of the track.
One handy way of keeping things natural sounding is to set up a duplicate channel for your vocal, and have the auto-tune plugin on that. Then you can go through the whole vocal track, and decide which parts (often just a single word or phrase) actually need correcting, and which will be fine as they are. In a lot of soulful, or lo-fi sounding music, a bit of a wobble can be a good thing; it adds character and emotion to the track. You wouldn’t want to iron all this out. But for the odd mistake where the singer really does hit a duff note (and you can’t get them to re-record) then you can chop the audio out, and put it on the auto-tune channel. This will hit the worst offenders, and leave the rest of the track intact.
Then, if you’ve got compressors or limiters on your vocal track, try to leave the pitch correcting plugin until after these in the signal chain. Sometimes if there are any audible artifacts from the auto-tune, the compressor will bring these up in the mix. Which is undesirable – so get the compressor in first, and then auto-tune afterwards.
Of course, like most plugins, auto-tune can be abused in various different ways to create some highly interesting (or amusing) sounds. Put a big keyboard pad through one and start pitch bending, or try a drum track to get some very strange effects indeed!
Auto-tune is actually a lot more versatile than most people think – and a lot more widely used. So check out the options that come with your DAW and try getting your hands dirty. It just might make your tracks that little bit more professional sounding!