Are your synth lines not really cutting the mustard? Does the top end lack a little fizz, or do you find the lows to be a touch inconsistent? Then perhaps you should indulge in a spot of layering…. When people discuss ‘layering’ up synth lines, they’re usually talking about getting the same MIDI part playing on two or more synths at the same time. There are plenty of reasons why you might want to do this, and a few why you wouldn’t, and that’s what we’ll be examining here. The first, and arguably most common, reason for layering up your synths is that you want a bigger sound.
If your lead line isn’t quite cutting through the mix, then try doubling it with a fizzy sound, high-pass filtered such that it doesn’t clash too much with the main line (at least above 1 – 2kHz). In general you should be looking for a fairly subtle effect; take a simple synth patch, blend it in very quietly, and make sure it’s doing only what’s required. The majority of the character of the sound should be coming from the main synth patch; if you start trying to get several big and crazy synth lines playing at the same time you’ll only end up in mixdown hell as you try to compress, sort out phases and automation and volume on several synths simultaneously. To this end, don’t be afraid of using presets or simple sounds for any synth layers that will secondary to the main sound, although many producers like to stay away from presets for reasons of originality, here you’re just using it as a tool, to bulk up another sound. It’s the main patch people will be listening to, so just grab something that works and move on!
Similarly at the low end, many big synth patches make great bass sounds, but don’t quite cut it for sub-bass. In this case, try high-passing your synth at something like 150Hz (or perhaps even up to 200Hz if it’s getting muddy in your mixdown) and layering in a straight sine wave for the sub bass. Again, simpler is better, and a sine wave is perfect for sub bass. Be sure to make the volume envelope match that of the main synth (or at least make sure it will sound good on a system, by giving it a touch of decay and release), add a touch of compression and you’re good to go. It really doesn’t need to be any more complicated than that.
When layering a new synth line to complement an existing patch, you need to make sure it matches your main patch in a number of ways; chiefly volume, space and filtering. If your main patch filters up and down, make sure your layers do likewise to avoid leaving them high and dry (try sending them all to a buss and filtering that for simplicity). Send your layers to the same reverbs for consistency, and if your main patch moves around the stereo field, then ensure your layers do too. If the volume of the main patch changes, then reflect this in the layers. Paying close attention to all these points will help the layers blend in with the main patch much more than anything else. So many forum heads will insist that you jump straight in with frequency analysers and multiband compressors, this is a tricky and complicated way of solving a problem that can often be avoided!
On the subject of filtering, one common reason for requiring layering is that when you change filter levels, the weight of the sound can change with it. For instance if you’ve got a chunky bass sound with a resonant low-pass filter on it, then when the filter cutoff is at a low frequency, the resonance will give you a boost at those low frequencies. But then when you turn up the cutoff, the resonant boost moves, great for giving that acid adrenaline feel, but it doesn’t help when you wanted to keep the low-end weight. So in this case, it’s often helpful to double the synth patch with itself, and have one patch with the filter down, low passed and unchanging. Then high-pass the other, and you can alter the filter as much as you like, without affecting the weight of the patch.
Another area where layering synths can come in extremely handy is with samples, especially melodic samples taken off an old vinyl. Typically, these may be badly recorded, lacking in high or low end (or both) but will usually have loads of character. So in cases like these, you can use the same techniques, get an unobtrusive synth patch, programme it to match the sample, and fold it into the mix as subtly as you can to fill out the sound. With a little tweaking, you’ll end up with a full-spectrum sample that sounds crisp and finely EQ’d but that still keeps all the character of the original.
The possibilities of layering up your synth sounds go well beyond the scope of this article, but this should give you a few ideas on how to proceed! The golden rules are to keep it simple, make sure you program the layers in detail to keep them true to the main patch, and watch out for clashing or overlapping frequencies. Once you’ve taken heed of these, feel free to layer away….