Riding the Buss!

You'll have seen all those buss channels on your mixer or DAW, over there to the right - like normal channels, but you can send and group all sorts of signals together. But are you really getting the most out of this part of the mixdown process? Read on, as we take a look at some tips for using busses to help your sounds...


The most common use of a buss, especially in a modern DAW, is for FX sends. Put a reverb or delay on it, and use a send from your channel to that buss. This is a useful alternative to putting a reverb on your individual channels; as it offers you a lot more control. You can adjust the effect volume by changing the buss fader, rather than going into your plugin and fooling around with the wet/dry balance. You can even put effects on the effect - for instance, if you wanted to high-pass your reverb to avoid it sounding muddy, or put some stereo widening on it; this is easy to do on a buss channel, as it will only touch the effects. If you tried it on the original channel you'd alter your whole signal.

Using effect sends like this also enables you to put the exact same effect on several channels - useful for giving a coherent sound where everything sounds like it's coming from the same place.

So, FX sends are definitely useful. But what about taking the whole output of your channel and bussing that? Well, just doing that with one channel won't be very interesting. But you can use this function to group things together, and that can be a powerful tool for enhancing your workflow. If you group all your drum tracks together in this way, then when you're trying to find the right balance for your mixdown, you can easily pull all your drums down by 2dB without having to individually adjust 20 or more channels. Similarly, if you feel your drums need more treble, you can do this at the group stage without having to add an EQ plug to every channel. This saves both time, and CPU power!

Once you've grouped your sounds together you can even - and this is where the modern DAW really comes into its own - send things to other busses. If you're not careful this can be a great recipe for confusion, but on the other hand can enable you to quickly and simply add effects to many sounds at once. Parallel compression is a classic example; we had an article on this some months back, so this isn't the place for a detailed explanation, but try an FX send to another buss, compress it heavily, and then mix it in quietly behind the original signal. You can try the same with distortion, valve emulation, and plenty more.

One useful psychological trick with busses is to help you look at your sounds afresh. When you have effects and plugins on your standard channels, you can get to thinking that because you have addressed a problem, it's solved. For instance, you might have used EQ to take some of the weight out of a guitar part, but not gone far enough. But you thought you'd sorted it. If you work at the buss stage (or, even better, bounce down stems from your busses and start a new mixdown with just 6 - 10 audio channels) you won't become distracted by the fact that you already EQ'd the guitar part, because you're not looking at the plugins you've already added. You'll be able to hear more clearly what needs to be done, and take action accordingly. Busses also enable you to get a bit more clever with sidechaining. A simple example might be if you wanted a pad to sidechain off both the kick and snare; you could send these two channels to a buss, which has no output. Then compress the pad off this buss. Or (and we're getting complex here) a useful technique for de-essing can be to send your vocal to a buss, and bandpass it savagely around the frequency you want to reduce; so you're left with nothing but the offending sounds. Then turn the output of that buss off, and you can simply sidechain your main vocal off this.

As you can see, busses can be a hugely useful tool in mixing efficiently and getting a good coherent sound out of your mixdown - even helping you look at the whole mix a little more holistically. But they can also be a very quick route to a complex and and confusing channel structure, so remember to keep things as simple and straightforward as you can manage! So, if you're ready, put on your thinking cap and get routing. It might just make the difference you needed to your mixdown...

Give Me Some Space!

Are you having trouble keeping all your sounds distinct? Are you finding that your tracks sound cluttered, with everything jostling for the same space upfront? Then read on, as we take a look into the art of creating space with reverbs, panning and dynamics...

The idea of "space" in a mixdown is a funny, and slightly nebulous concept, but basically it's about making things have their own place, and making certain groups of sounds (for example, your drums) sound coherent with each other. There are a few ways of doing this; panning is the most obvious - move a sound left or right - but there are other tools you can use too. Reverb can create an atmosphere, and move something back from the front of the mix, as can use of dynamics processing (or avoiding it!) and even delay.


But first, let's look at panning. It's the simplest way of separating sounds out, and creating a more interesting mix. Panning something to one side can be a great way to catch the ear of the listener; and is very useful for effects, percussive noises, pads, and other things that support the overall sound. In general, you should have the really important things in your mix (kick drum, snare, bass, lead vocal etc) panned centrally - you wouldn't want them to disappear on a mono club system - but after this you can shift things around subtly. It's often useful to pan fairly major sounds just off-axis, for instance 20-30% of your pan-pot's travel. This stops them contributing so much to the clutter, but won't make them seem distractingly off centre.

Less important sounds can be panned much harder; incidental bleeps and FX can safely be moved right off to the side, and certain percussive sounds like tambourines can support hard panning too. But remember to be balanced about it; if you move your tambourine to the left, move a shaker or bongo off to the right. A lop-sided mix will not only sound odd, but if one channel is significantly louder, will reduce your ability to get a decent volume from your master.

Reverb is a more complex beast but there are a few simple things you can do to help your mix. First, consider that the point of reverb is to make something sound like it's in a particular place - a room, or a hall, etc. So it's not always a great idea to have lots of different reverbs in a track - you may end up with everything sounding like it's coming from 10 different places at once. Start by setting up a short reverb (maybe around half a second) and sending certain drum sounds to this; snares, claps, maybe hihats. Mix it very quietly (and then turn it down a bit more) - you should find that it gels your percussion together subtley. In general, it's good to use a reverb on a buss instead of individual channels; it ensures that things are using the same space for coherency, and saves on CPU power.

Larger reverbs can be used for properly "placing" something rather than just gluing things together; it can work especially well on pads, strings, lush sounds, chords, and sometimes vocals. A large reverb will push a sound "back" in the mix. As such, using one on a busy part, or a part that requires impact, may just clutter the sound and stop that part having the punch it needs. Bear in mind also that another way of pushing something "back" is simply turning it down. It's qualitatively different, of course, but one can easily get into the trap of putting a large reverb on something, then turning it up because it's now so far back in the mix. So it's important to play around with the level of the reverb tail, and not go overboard with it. Sometimes the pre-delay setting on your reverb will create most of the effect you want; letting you keep the reverb level down, so try different settings here too.

Like a reverb, and in particular like the pre-delay, you can use an actual delay plugin. Use a very short delay time (tens of milliseconds), set it so that the delay signals lose some high frequencies (most delay plugins offer this function) like they would in a real room, and set the wet signal very quiet. This will give the effect of room reflections, but often without some of the muddiness you can get from a reverb.

Lastly, and it sounds simplistic, but dynamics are crucial too! As mentioned, louder things sound more towards the front the mix. This much is obvious, but the upshot is that if you compress your sounds, they lose dynamic range, and they become loud from start to finish (think of a snare that you've squashed the transients from - it's now like a block of sound). The effect is that everything is at the front of the mix, and all your hard work with delay and reverb is negated, because your tracks are squashed into one small dynamic space. So lay off the compression if you can, let your sounds breathe a little, and they'll be much easier to place.

Space in a mix is a complex beast, and it's not something you'll master straight away. But by trying some of the techniques above, you should start to make some headway into more balanced, natural sounding mixes. So give it a go!

Lessons in Compression Part 2

Still not quite sure on how and when to use a compressor in your mix? Hankering for some more details on how you can use them to sweeten up your tracks? Well, read on as we continue our introduction to the murky world of dynamics processing...

There are two main ways of using a compressor - there's "problem solving", in which you want to achieve a particular solution, and "creative" use, which involves radically changing a sound, and generally will utilise some fairly extreme settings. We'll come to creative use later - but first, let's stick with those extreme settings for a minute.

Most people know the basics of what the various things on a compressor do, so we won't dwell; attack is how long it takes to kick in, release is how long it takes to reset back to zero, threshold tells it when to start working, and ratio by how much. But it's not always easy to figure what this actually means in the real world, so here's a useful trick when putting a compressor on your channel. Set it up initially with a high ratio (let's say 15:1 or more) and then bring down the threshold so that you're taking off a large amount of volume - maybe 20dB.
This will make your channel sound like a horrible mush. So don't leave it like that. However, it will also dramatically emphasise the effect of the attack and release. Change these settings and you'll see that a long release (hundreds of ms) will track slower volume changes - like the difference between your singer's loud chorus and quieter verse – while a short release will reset rapidly between notes, evening out the level of individual hits, but leaving the larger scale stuff untouched.

At the other end, a short attack (i.e. 10ms) will cut things off sharply like a limiter, making your drums (for example) able to achieve a higher overall level, albeit at the expense of a lively, dynamic sound. A longer attack (i.e. 40 - 50 ms) will allow a transient through but may squash the body of the sound; in this way you can control the overall level while retaining a certain natural feel. Alternatively, you can use this setting to emphasise transients.

Listening to the channel like this should give you a clear view on what the compressor is really doing. So once you've tried various attack and release settings, and they're now doing exactly what you want, back off the threshold to a more moderate level. "Moderate level" is, of course, relative and depends on what you're processing, but you should alter it in conjunction with the ratio.

For something that needs to feel kind of natural, like a vocal, acoustic guitar or even an old soul sample, then it's important that your compressor isn't suddenly yanking down the volume. So a low ratio (like 1.5:1, or even less) coupled with a low threshold (such that the compressor is removing around 3dB) will mean the compressor is triggered often, and consistently nudges the volume down. This will feel more natural than a higher threshold with higher ratio; the overall effect may still be that the volume ducks by 3dB, but if it happens abruptly then the effect may not be very musical, and unsuited to a more delicate sound. It might sound great on a bass or drum track though; something with a bit more energy.

People often wonder where in the signal chain the compressor should go. As always, it depends, but as a general rule of thumb any 'fixing' should go before the compressor. For instance if you've got some hiss on your channel, then a compressor can make this sound louder - so try to remove it with EQ, gate or noise reduction before it gets to the compressor. On the other hand, if you want to boost part of your sound with an EQ, then you might find that the part you've boosted is now triggering the compressor, and being turned straight back down again. So in this case the EQ should go later.

It may sound advanced, but don't be afraid of having two compressors one after the other. If you feel you want to to tame some peaks, but also control the overall level of a part, it's no crime to have a compressor with a short attack and release followed by one with longer settings. But be careful - the more compression you use, the easier it is to accidentally squash the life out of a sound!

Creative use is a completely different kettle of fish, and you can pretty much discard the rule book. For a good example of the "extreme" settings mentioned earlier, take a listen to someone like Flying Lotus or Rustie. Check out the way pads, FX and hiss drop suddenly out of the mix and then surge back - this is created by having low thresholds, lopping off 15 or 20 dB with a heavy ratio and a long release of 200 - 400ms. For a soft sound like a pad, this can also be triggered with a sidechain input, for instance the kick or snare. Or, you may even set up a channel that has no sound output, and its only purpose is to trigger a sidechain.

Compressors driven hard like this can change the sound dramatically - try pushing a sub-bass heavily through a compressor or two, and you'll hear it create higher frequency harmonics that weren't there before, as it tries to keep up. You can also try some sound design effects - layer up some delays and reverbs on a sound, then squash them hard with heavy compression. Do this a couple of times and you'll end up with a shifting pad or drone sound full of atmosphere.

As we mentioned at the start, compressors can be confusing, and difficult to use correctly. But if you follow some of the tips above, and make sure you're definitely improving the situation with some careful A/Bing, you should find the fog starts to clear a little. So fire up that plugin and get listening!

Lessons in Compression Part 1

The compressor. Possibly one of the most mystical, misunderstood, and yet even simplest tools in the producer's arsenal. It has the power to improve or ruin any mix. Can you be sure you know when to draw for it? Join us for a quick tour of how, why, and when to use a compressor...

Although a compressor is a simple tool - Let's be honest here, it's essentially just an automatic volume knob - For many, it's something that causes a lot of confusion. Much of this is put about by forum users pushing forth received wisdom, and leads innocent people into some strange practises. We could write a whole book on when or when not to use a compressor, but let's look at a couple of basics.

Firstly, not everything needs compression! This might sound obvious to some, but I was recently teaching a student who, as step one when creating a new channel in his DAW, put a compressor on there. Just because, "you know, compressors are good". It's unfortunate that people end up in this mindset, as it will certainly hinder their mixdowns.

So it's very important to consider, then, exactly why you're putting that compressor on your channel. What problem are you trying to solve, or what effect are you trying to achieve? If you don't know, then it's probably best to leave it off for the time being. There's no inherent problem in not compressing things much, if at all. It's only a very recent development that we've been presented with the chance to have compressors on every channel anyway - Until a just few years back, a compressor was a hardware unit and most dance music producers would only have a couple. So they'd have to be a lot more considered about what gets compressed, and how to work with dynamic range otherwise.

That leads onto the other point - With audio production there are many ways to skin a cat, and often a compressor won't necessarily be the easiest way to get what you want. If you have a synth or vocal line with a couple of occasional louder parts that you want to tame, it might well be easiest to just draw in a bit of volume automation at those points, rather than trying to set up attack and release times. Similarly, if you wish to tame a transient on a snare, it might be easiest to lop off the top with some subtle overdrive, which can be configured relatively easily.

In fact, one exercise which I'd recommend to anyone, would be to write a track with no compressors at all. With transient shapers, distortion, overdrive, hard-clippers, de-essers, limiters and volume automation you can achieve more or less everything that a compressor can do, and it will get you thinking more analytically about exactly what you need a compressor for in the first place.

So then - Enough of when you shouldn't be using then, what DO you need a compressor for? There are two main ways of using one (and indeed any effect) - For creative purposes, i.e. to radically change the sound to make an interesting effect, and for fixing sonic problems, or helping things sit in the mix more comfortably. Looking at the latter, a compressor is probably best used on busy tracks when automation or other solutions would be unfeasible. If you find that you can't quite seem to find the right level for a channel – too loud in parts, too quiet in others - Then it's probably a good time to reach for one. Or, if you have a buss and you want to glue the sounds together a little, by letting some smoother sounds duck under some more vibrant ones, a compressor may help here too.

A good place to start would be with the presets on your compressor. If you're new to the compression game and wish to process your drum buss, then see if you've got a 'drum buss' preset and go from there; if you don't think it's doing exactly what you want, then try tweaking some settings (more on these later). But the key things to remember are to make sure you're not making things too complicated, and that you're actually improving the situation. Be ruthless, and make good use of the "bypass" or "compare" function on your plugin. If it's not actually helping, then go back and start again!

So, these are some general tips to get you thinking - Join us next week as we go more into the specifics of ratios, thresholds, attack and release....