Posts Tagged ‘ Mix-bus ’

Five secrets to making your mix louder

Don’t dismiss this post yet! Even if you’re in the ‘more dynamics’ brigade, these tips will give you clearer mixes that suffer less in mastering. That means better-preserved dynamics and higher fidelity!

For those of you who really do want your mixs SUPER LOUD, this tips will let you push more volume without your sound turning to mush.

  1. Go easy on the bass. That includes sub bass, kick and melodic bass. It always tempting to turn them up, but the low frequencies really use up a lot of headroom (high peak level for the same perceived volume). The more headroom your audio needs, the less you can push it in mastering and the worse it will sound when it’s pushed hard. First try to compare your bass levels with commercial reference songs. Listen carefully to the level of the low frequencies in comparison to the rest of the spectrum – you might find there’s less than you initially thought! Also consider saturating the kick or the bass.
  2. Saturate those peaks. Take a look at your mix bus peak meter to see if any tracks are ‘poking out’ of the mix – often it will be the kick or the bass. Used carefully, you can use saturation to reduce the peak level of your kick or snare tracks without reducing the perceived volume. Often peak level reductions of 6-9dB are easily attainable without adversely affecting the audio quality. Limiters are usually not so useful here because they’ll tend to change the sound too much.
  3. Embrace the background. Push some instruments further to the background. If you try to put too many sounds in the foreground you’ll end up with an indistinct mush. This indistinct mush will quickly become even worse when you apply heavy limiting in mastering. Instead, try to identify the three or four most important elements of the mix (typically the snare, kick, bass and lead synth/vocal). Be bold and push everything else to the background! You’ll get a mix that’s more focussed and more powerful.
  4. Leave your stereo widener at home. Stereo widening tricks might be fun to play with, but they’ll rob your mix of punch and power. If you want those foreground sounds (snare, kick, bass, lead) to hit as hard as possible, stay clear of any stereo width manipulation. Some subtle widening is sometimes useful for special background effects, but remember – if you do it, do it in moderation.
  5. Be careful of the lower mids. The region between 100Hz and 1000Hz is the cause of many troubles. It’s very easy to put a mix together that has a lot of mud build-up in that area. To get the ultimate clear mix, get brutal with an EQ! Make some big dips in the lower mids for all background instruments, and make sure you don’t have any excess lower mids in your foreground instruments. You need to keep some lower mids, because that’s where your body and thickness comes from. Here’s a secret though – a mix with body and thickness only needs a few foreground instruments to have that body and thickness. To put it another way, a few fat foreground instruments makes for a fat mix. A lot of fat instruments makes for a flabby mix.

With these mixing tips you should be able to get a few more decibels of clarity in mastering!


Five compression mistakes and how to avoid them.

Compressors are complex tools and, like most other audio engineering tools, there are more ways to set them up ‘wrong’ than there are to set them up ‘right’. If you’re careful though, you won’t fall into these common traps:

  1. Too much gain reduction. You know you’ve done this when you’ve got tons on gain reduction and you’re thinking to yourself: “It sounds great but I can’t get rid of this massive click at the start of every transient.” The click is from the attack time. Not only does it sound silly, but it will rob you of your headroom. Clicks like that are similar to deep bass – they’re not very audible, but they can easily take up a lot of level. Solution: Either use less gain reduction (you probably don’t need that much!) or use a limiter instead of a compressor. Another approach is to use a limiter after the compressor. Heavy-sounding compression is often the result of fast attack and release times rather than a deep threshold.
  2. Using compression to fix non-dynamic properties of sound. You know you’re doing this when the sound you’re compressing has no dynamics to begin with (such as a synth bass/pad/lead). When you compare the sound with and without compression, the dynamics don’t change, but the tone or harmonic content changes. In this case, the compressor is not the best tool for the job. Solution: Listen to the dry sound and consider whether you actually need a saturator or EQ. Next time, get out of the habit of inserting a compressor on every sound without first deciding if compression is what you really need.
  3. Using mix bus compression as an alternative to mastering.  You know you’re doing this when you’re rendering your mixdown to a file that will be burned straight to CD or encoded to MP3, and all you think you need to do is ‘make it louder’. Mix bus compression has its uses, but it’s not the right tool for achieving raw loudness. Solution: If you’re in a rush and you don’t care about quality, then use a digital limiter set to kill and call it a day. If you care about quality, either take the time to do it properly, or find someone to do it for you.
  4. Using mix bus compression as an alternative to working hard in mixing. Don’t be lazy! You know you’re doing this when you’re trying to use your mix bus compressor to change the sound of an individual element in your mix. Don’t use mix bus compression to address a kick or snare that is too loud – it will have unintended effects on other mix elements too. Solution: Don’t be lazy. Go back to those individual tracks that need fixing.
  5. Using side-chain compression to get two clashing parts to work together. This is using a sledgehammer to crack a walnut. As above – don’t be lazy!  Side-chain compression can be useful as an effect, but it’s certainly not necessary for simple mixing tasks like getting vocals and guitars to work together. Solution: Use tone and depth to separate sounds. More on how to do this later.

If you can steer clear of these common mistakes, you’ll be well on your way to effective compressing!


Sweetening your mix bus, and why you shouldn’t wait for mastering to do it

There’s a case to be made for ‘sweetening’ your mix bus.  Many mixes can benefit from some subtle processing to bring out the best qualities of the tone of the mix and to use dynamics to give the mix a more compact, controlled sound.

To bring out the best qualities of the tone of the mix, an EQ is the most appropriate tool. For this task, however, don’t reach for your highly-flexible ten band fully parametric equaliser. Instead, go for something with character and vibe – not just in sound, but in workflow. The idea here is to use something with fewer controls, but where each control does something interesting. The recent Pultec-modelled EQ plugins are a good choice. The reason for this is that this tonal adjustment isn’t a corrective task where surgical precision is requied. It’s artistic, impressionistic. You’re trying to be creative, to add colour, to make it interesting.

To use dynamics to give the mix a more compact, controlled sound, compression is the most appropriate tools. Unlike individual track compression, the best results here are achieved by being subtle. You don’t want to completely change the dynamic behaviour of the mix. Instead, focus on less than 3dB gain reduction, and configure the compressor to simply ride the gain. Use high ratios when you want a pronounced effect, particularly on mixes with very little dynamics (such as rock music or dance music that is almost always at the same level). Use very low ratios for more dynamic music (coupled with a lower threshold to catch the lower-level audio). Faster attack and release times will produce a more pronounced effect, whereas slower times will be more more gentle and transparent.

The real tip here, however, is to do all this at the mix stage – not mastering. The mix is where you’re focussing on creative sound adjustments, on making the song sound special. Mix bus processing clearly fits here. Mastering, by contrast, should be as transparent as possible – focussing on preserving the creative decisions that were made during mixing and translating that sound to the target playback format.

The best time during mixing to apply this sweetening is at the very last stage – after reverb and panning, just before rendering or recording the stereo mixdown. This is when you’ll have the best perspective to apply processing to the overall sound. Otherwise you may end up chasing your tail in circles as further track-level changes necessitate mix bus changes.


Reverb on the mix-bus

Under most normal circumstances, using reverb on the mix bus is no different to using a send on every track, with every send set to the same level. Usually this it not a good idea – it’s better touse sends to apply reverb in different levels to different tracks. Some sounds can ‘take’ more reverb than others. Some sounds need more reverb then others to emphasise the depth in the mix. A send level of 0dB (unity – meaning the reverb is the same level as the dry sound) might still be not enough for sustained sounds like pads and organs. On the other hand, a send level of -21dB might sound extremely wet for staccato sounds or hand percussion.

Having said that, there is a place for mix-bus reverb. While it’s not as refined or tailored as using individual sends, it is much faster. I’ve done it myself on occasion when I’ve had a project that’s up against a hard deadline. Mix-bus reverb also sounds different to individual sends when it’s placed after other mix-bus processing, such as compression or other dynamic effects (for example, NOT eq). Whether this sound is useful for you and worth the greatly-reduced flexibility is up to you.

Reverb in mastering is a slightly different matter. In this situation it’s too late to adjust the reverb in the mix, so it can only be applied to the stereo mix. Reverb may also serve a slightly different purpose when used in mastering – to make all the songs in a release have a similar ambience. This might be particularly important on compilation albums or albums with a wide variety of sonic approaches.


Mastering versus mix-bus processing

It’s a murky world, this mastering.

Mastering is a process by which a mixdown is prepared for distribution. Traditionally, this has been performed by a dedicated mastering engineer with specific skills and equipment. The esoteric skills and expensive equipment gave the mastering engineer a sort of mythical status. No-one outside the mastering studio really knew what the engineer was doing, other than ‘making it sound better’, or ‘sprinkling magic dust on the record’.

Today, music technology is affordable enough that almost anyone can start creating recorded music with not much more than a computer. These recordings are often self-published online. In many cases, the audio that it heard by the listener is exactly what came from the original computer that recorded it.

Even though no dedicated mastering engineer is being used, there is still a ‘mastering process’. Sometimes this mastering process consists of little more than rendering the mixdown and encoding to MP3. Sometimes it might be an elaborate process of mix bus plugins, comparisons with other songs, advanced multi-band processing and more.

The confusion lies with the deliniation of processes. Mastering is a process performed by people. It may also include modifying the audio, using means that are sometimes used in mixing. More confusingly, these means are sometimes used in mixing, but in a processing chain that is similar to mastering (such as using plugins on the mix bus).

So, to clarify:

Mixing is a process of combining the individual elements/instruments and balancing them so they all work together. The end result is a mixdown.

Mastering is a process of taking the mixdown and preparing it for distribution. The end result is music that translates well to all the expected playback scenarios.

The mix bus is a way to apply some mastering-type processing while mixing. Not all processing on the mix bus is actually mastering though – it depends on the intent. For example:

  • Mixing into a bus compressor is not mastering when it’s done to help the different sonic elements fit together.
  • Using an EQ and limiter on the mix bus is mastering if it’s used to balance the overall tone and ‘loudness’ so that the music sounds best in a mixed playlist.
  • Using a limiter on the mix bus is not mastering if it’s used to make the sound pump in time with the kick drum.

While mixing and mastering are two different processes, the use of the mix bus makes it possible to overlap them so that mixing and mastering are both done in the same environment.

Additionally, not all mastering processes can be applied on the mix bus. Trimming and fading is usually done in an audio editor. Encoding to mp3 or burning to CD are best handled by dedicated software and hardware. Preparing a collection of songs for an album usually can’t be done in the same environment that was used to mix them.


Monitoring gain staging

The reason the commercial references are so loud is that they have very little headroom – the average level is so high that there’s not much room for the peaks (which have been squashed down). When mixing, however, you shouldn’t worry about headroom on the mix bus. You need to give yourself enough headroom that you can focus on the task of mixing – getting the balance between the different sounds right. Wait until mastering before you tackle the “mastering loudness” problem.

If you try to mix at commercial levels (with extremely low headroom) by using a limiter on the mix bus, you’ll have an extremely difficult time of it because every small change you make to a sound will change the other sounds in noticeable and largely unpredictable ways. For example, if you turn up the vocals, the bass might become quieter (because everything becomes quieter). Noticing the bass, you turn it up, which might make the whole mix more distorted (particularly if you’re using saturating processors on your mix bus). It also causes problems because setting a channel to solo causes it to sound very different to how it sounds in the mix (because it’s being modulated by the other channels).

To make sure you have enough headroom at mixing, simply turn your speakers up. Turn the volume up much higher than you would have it for regular listening. Don’t use any processors on your mix bus. Your mix will end up “quiet” (because it’s much further from 0dBfs than your commercial references), but don’t worry. Mastering is a separate process, and one of the purposes of mastering is to bring the overall volume up to its final level.

By doing this, you are free to focus on the mix.


Multiband compression

Multiband compression is a complex and subtle tool. Compression itself is one of the most complex single processes commonly applied in mixing. Multiband compression multiplies that complexity because it applies several compressors in parallel, each processing a different frequency range of the audio. Because of the way the audio is split by frequency, multiband compression is best suited to complex audio with varying dynamic behaviour across the frequency range. Typically, this would be a full mixdown (either on the mix bus, or in mastering).

Multiband compression is best used for one of two purposes – surgical problem solving, or subtle leveling.

Multiband compression is ideally suited to some kinds of problem solving because it allows compression to be applied to a specific frequency range without altering the rest of the audio. For example, a mix with uneven bass guitar playing could be improved by using multiband compression to reduce the dynamic range of the low frequencies. Another example could be a mix where the vocal has not been compressed appropriately and alternates between being too quiet and too loud. Depending on the mix, multiband compression can be used to even out the vocal in relation to the rest of the mix.

In these examples, multiband compression would be used at the mastering stage only if it’s impractical to revisit the mix. Of course it is better to fix these problems in the mix (or even earlier) if at all possible.

The other common use for multiband compression is for subtle leveling. Rather than using a single band to solve a specific problem, all bands are activated and are gently riding the gain. This approach works best on weak mixes that are not balanced very well.  It improves the overall tonal balance and dynamic behaviour of the mixdown in a more subtle and less damaging way than full-band compression. Again, this approach is appropriate if it is impractical to return to the mix. 

As always, the earlier these problems can be addressed, the more power you will have to apply the appropriate solution. Don’t wait until mastering to fix things that should be addressed in the mix! Likewise, don’t wait until the mix to fix things that should be fixed in recording or even composition!