Posts Tagged ‘compression’

Expansion, the lesser known dynamics tool

Hi people!

Apologies for taking so long to get another article written. Been rather busy actually working on stuff.

“But Tone, what about the multiband series??”. Well…I had intended to make screencast video’s, showing and explaining with narration, exactly how to get one of these things setup. But the fact is, making them takes an age to do. So I’ve drawn up a new plan, where I will be making sets of tuition vids on many of the different areas of mastering, and the tools used. These sets will then be purchasable from the site. If you want an idea of what I have in mind, take a look at the talented Nick Maxwell’s site Nickstutorials.com .

I had never intended this to be any kind of ‘pay for’ site. But to give the best advice on tips and techniques takes a long time. So it’s a natural progression. Keep checking back for small demo’s of what will be available(when I get some time). I will however continue to post articles.

My goal remains the same…to hand on tips and methods to help you better understand your audio work, and get the best from it.

What is expansion

Simply put, it’s the exact opposite of compression . It’s main use is when working with already over compressed material, to add back dynamics. I was actually inspired to write on this subject, after working on a 70’s restoration job that needed a different approach.

The material came from LP, which as far as I can tell, had been kind of mastered by the guy who cut the disc. It’s full of nasty notches, a large wide mid lift(totally covering the low end) and a very thick sounding bass guitar. Don’t forget, this is an old recording, even if no compression was used during tracking and mixing etc, this has gone from 2 inch multitrack to 1/4 inch reel, then onto vinyl and back into digital. Plus with all the parts of the spectrum missing, it’s quite a strange sounding recording. Anyway, compressing the bass region was a no go, ….not immediately anyway. So here’s what I did:

So, to give me a more balanced start point, I used a multiband model, and expanded either side of the bass hump(which covered 80-200hzish) using shelves, plus a couple of  other expansion lifts at 190 and 250ish to keep the warmth in the vocals. I also used longer release times than I would normally, as the dynamics either side of the hump are jumping about all over the place.

What this effectively does is this: as the bass hump approaches threshold, the upper and lower shelves lift to match it “but Tone, now the whole thing is bouncing up and down”, yes, but that’s the point. Now I have a sound that I can start to push into shape, using the normal methods.

For anyone thinking “why didn’t you just compress the mid using multiband compression”, I did try that first, but it worked much better expanding first, and then using a small amount of mb comp to tighten the whole thing up. Sometimes, the way things are mixed, and the problems that are put in, need dealing with differently.

Setting up

1:Have an idea of what you want to achieve

2:If you’re using multiband expansion, find the places where you want the lifts. Find the sweetspots where the upper and lower shelves need to be, by using a small expansion ratio first, maybe 1.03:1 for example. Use a small attack time like 5ms. Too short and the expansion isn’t going to work right. Start with 100ms release. Set the threshold by hearing the blend. Don’t look at the meters!. The ones on my fav model are totally misleading(done on purpose I think).

3:Adjust ratio/amount of expansion to suit on each band.

4:Adjust attack times. Concentrate on the attack part of the music. Don’t be put off by a slightly wrong release phase at this time.

5:Blend in the expansion by adjusting the release times. Drag it around all the way from 50ms upto 1 second. Forget the numbers and dial in the sound you want.

6:Once you’ve done all that, go over the settings again and make sure it’s all working together.

Setting up a standard wide band expander is just the same as for a compressor. Set enough attack time to allow the kick through.

Once you’ve found the attack and release region you want, I find there is usually a few ms to play with for artistic input. That 1 extra ms on the attack can create a tiny delay, which can be very creative, and similar with release. Listen for a delay or hole(attack too long) or a slight thickness (attack to short). Similar deal with release times.

Conclusion

I know not everyone needs to use expansion, but it’s a powerful tool that will go some way towards fixing bad compression or mix problems. Next time you’re working on a mix where the kick is a bit loud, think “Do I want a thicker kick, by using compression, or should I lift the rest first using expansion, and then deal with overall compression.

A fellow M E recently told me “I know quite a few mastering engineers, and we all get to the end result in slightly different ways”. It’s exactly the same with different material. You could own the best compressor in the world, but it’s not always going to be the best tool for the job.

I’ll ask my customer if it’s cool to post before and after for you guys to hear.

Next up I’ll be explaining the very powerful m/s eq. So be sure to stop by real soon.

Till then, thanks for reading

Tone

Multiband compression part2

Hi

So, where were we???. Besides me regretting trying to write about such an awkward subject . As I mentioned in part 1, you need to make an assessment of what needs doing, before jumping straight on the controls.

Common example:  Heavy sub end (under 70hz) with Little or no need for compression. The idea here, is to find the crossover point for band 1/2. Like a cut off freq for where the compression stops. We can then bypass band 1, or use a small amount of gain reduction purely to blend with the settings through the other bands.

The green area through the centre, shows the compression curve. The most gain reduction being in the mid area, less at the top (squashed hi’s aren’t pretty), and least below 100hz.

Remember, this is basically a dynamic eq, and the green compression line, with its upper and lower boundaries shows that graphically.

Thinking of it as a sort of eq, may help you to realise, that for this thing to work, all it’s parts have to be working as one. The spectrum has to join together at the right times.

Setting up

As I said before, soloing in mastering can be pretty useless, as we’re working on the whole sound. First steps with a multiband compressor can be an exception. To get the main ‘problem band’ pushed into the right shape, may be easier in isolation. We first need to set the amount of gain reduction, and get the release time where it sounds right, so we can then match the other bands to it.

So…solo the problem band. This is usually band 2 (70hz ish to 500hz ish) or band 3 (500hz ish to 4kish). Those are VERY rough freq examples, the point being, the most energy in a track is below 4k , and we don’t usually compress much under 100hz, as we want the sub end to move. I love tracks that go all the way down to 10hz, and with a solid low end, but over compressing under 100hz isn’t usually the answer.

So, with band 3 soloed for instance, begin by setting a starting ratio (maybe 1.7:1) Don’t forget…as with a standard wideband compressor, you want to be paying attention to the attack time. Setting it too fast will try to compress the front of the peak, and will usually make a bad job of it!. That peak power gets dealt with by the limiter later on. So initial setup is a case of finding attack and threshold.

Check out this little vid, showing me setting up band 3. This is a raw file, with no eq etc. It’s purely for demonstration. If the captions don’t show, Click the ‘CC’ button.
Note:Any compression artefact is from the source recording. I couldn’t use a compressor at all, 10 odd years back when I mixed this

Obviously I cheated, by setting it up before doing the screen cap, to keep it short. Band 3 here is the problem band. Not that it’s badly wrong or anything, but it needs slightly inflating to make it keep up with the low end. This is a classic use of multiband, dealing mainly with the mid section. Remember….match the wrong, to the right.

Once this band is roughly setup, it’s time to make the others work with it, and I’ll show that in the next part of this series. Once you have all the bands working together, it’s time to grab those global settings to get things sounding right. But remember….mastering is about striking a balance. You may set band 3 up just the way you want, but find you have to make a slight compromise to get the whole thing sounding natural.

Well, I’ve just accidentally hit the “Publish” button. So I’ll leave this article there. The screencast stuff will become a large part of future posts etc, and will include narration and more depth as I get better setup to do so.

Apologies for this post taking so long. As well as getting the video thing going, I’ve been hands on with some mastering projects. Oh…and there was Christmas .

I’ll start working on part 3, where I’ll be showing the setup through the rest of the bands.

Thanks for stopping by, check back soon, and please leave comments!

Tone

Coming soon……

Hi people!

Currently working on quite a big article, but it’s taking some time. I also want to add audio example content to it, which slows it down even further. But new stuff is coming in the next few days.

Keep checkin back!

Cheers

Tone

Compression as a creative tool

Hi all!

Continuing on the compression theme. I’m going to give some details on how to put it to some good use creatively, and hopefully put a positive spin on something that really gets a bad rap, due to being badly used by so many people.

Ever listened to a track and thought “how on earth did they create those anticipation build ups”. You know the ones….the verse is coming to an end, the volume doesn’t noticeably increase and start hurting in your ipod headphones, but you know something is coming, then bam!! into the big chorus!!, but still only a minor increase in overall level. Before I go any further, let me say this….A lot of people think this is done in mastering, and sure, we do have a small amount of control over that, but note the word ’small’.

If I want to do that over a whole mix, everything is getting slightly squashed, and one of my major hates, is flattened hi hats and cymbals etc!. There is also the possibility of doing this kind of technique with buss compression, grouping instruments together  and having a compressor over that group, but that’s a subject for another article. Take a listen to this clip:

(Apologies to all the electro dudes reading, this was the first thing to hand, and also a perfect demonstration piece. But the technique is viable across most genres)

Listen to the guitar on the left. I know the whole track increases in rms slightly, but that guitar is giving a very clear indication of ’something coming’. Now, to get that kind of increase in level, we have to do more than just make the guitar poke its head above the mix. That wouldn’t do what you want. Anything that is above the body of the mix by too much, just creates a problem. Especially for the M E.

So, put a compressor or limiter (depends on material) over the channel of that guitar(or whatever instrument it is) at post fader. I’m not going to give any numbers for your compression settings here, as that really doesn’t work!. Just keep in mind, if this track is going to be mastered, you don’t want to have squashed all life from it before it gets there. 2:1 is a good starting ratio.

Then for these ‘build up’s’, as you push that instrument up against the compressor with the fader, it will gain rms, ALONE, without ruining the space the other parts need to breath. Maybe experiment with varying the release time for different passages too. As I’ve mentioned in other articles, it will work in many places, giving a different feel with each. But there is right/wrong and artistic choice.

A track…a journey

The thing that separates the fantastic mixes from the “Hmmmm, nice but….” ones, are the mix approach itself. Everyone wants to blame their converters and eq’s etc etc, and I’m not saying those things don’t make a difference. But the real key, is capturing the listeners attention, by holding back, and then pushing forwards. Simply bringing an instrument in and then taking it out isn’t always enough, and small volume changes alone have to be kept small to keep the balance of the mix right.

Static mixes aren’t captivating enough, and I hear quite a few of them!. My attention span is about 20 secs. If nothing really changes in that time, my mind wanders off. Many people reading will probably wonder what I’m on about, but I clearly hear the tiny changes that for most listeners will go unnoticed, thanks to my over analytical hearing.

Learn to hear those changes. Dissect some of the best mixes from your favourite artists/producers. The best way to do this is by listening at a barely audible level, where you can only just clearly hear all the mix content. Then you may hear where the small volume dips/lifts happen.

Make a decision about what you want your mix to convey. If the instrument volumes stay static throughout the track, it will start….then it will end. Make it do something more in between.

Apologies if this article isn’t mastering focused, but it’s based on the frustrations I get IN mastering. Mixes that could have been awesome, but for a few builds and dips. Even the most fantastic sounding instrument can become monotonous if it’s too static. There are of course many other ways of creating interest, but this was mainly a compression article.

Till next time….thanks for reading, people

Tone

Compression part2

Hi people. Thanks for stopping by

So….where was I? . Release time…the most misunderstood control ever!. However, first I want you to have a listen to a couple of clips showing right and wrong knee slopes (as mentioned in part 1 of the compression…..again!!?? article)

I’ll re cap….The knee setting adjusts how fast the compression sets in. The biggest sign for me is how steady the image is. Have a listen to these and see if you hear it.

What you’re listening for is an unsteady image. It’s moving about slightly in the wrong clip, and more solid in the correct one. Don’t be too hard on yourself if you can’t hear any difference!. In tracking and mixing, this  isn’t really a big problem, but in mastering, it affects the whole sound. Possibly adding to a few more minor discrepancies to make one large one!.

Right, back to release times

The technical explanation….how long it takes for the compressor to ‘release’ gain reduction after the signal drops below the set threshold. Yaaaawn, What does it really mean??, it means  it’s a blend control, but make no mistake….it makes or breaks your sound!. My first subtle tip is this…..DON’T SIT LOOKING AT THE NUMBERS!!(and yes, I know there aren’t any on this pic  hehe). Shut your eyes and drag the release control around until the sound either blends , or pumps nicely, depending on what you’re trying to achieve.

As with most of the other controls, it will work in a few different places, I see it like the gain reduction stepping off of different parts of the mix, giving a different feel to the whole track with each, but check them all and find the best one for the sound you want.

Auto release?

Hmmm, some of the models get it right, but just check with a manual setting anyway, As I’ve said before, why trust your sound to a computer’s decision! . If there are big tempo/rhythm/instrument  changes in the tune, you’ll need to check the release times for each section. It really is a tempo based deal.  Some compressors offer a ‘hold’ function. This basically holds the gain reduction for a set period before going to the release phase. It’s just another blend control. With my main comp, I find the auto release and a small Hold setting does what I want. Be careful using higher hold times, as it can alter the feel of the material.

The most important control….

Is…….the gain control into the compressor!. No good spending time with all the other settings , if you don’t keep a good level through them. In fact, the more good work you can do with the track levels, the cleaner the compression will be. So don’t be afraid to ride it in places. One of the first things to do when mastering any track, is adjust the levels for each section.

What you’re looking to do, is keep the perceived volume about the same. Forget the meters!. This is to mainly make setting up comp and limiting a bit easier. Once I’ve got all the dynamics tools doing what I want, I go back and write the gain level into the compression in real time. Shaving 1 or 2 db off the input in places, can make for a slightly different feel.

Especially if you’re hitting the multiband first. Slight gain changes into that can be quite creative, but there’s not a lot of room for movement. Not enough gain can make the settings invalid (couldn’t think of a more human word for that), and hitting the thresholds with too much level will just squash the sound.

Once again, I’ve run out of words this time. There are a few more things I want to say on the subject, also a few more audio examples of right and wrong/creative settings etc. So if this has been of any help, be sure to check back for upcoming posts.

Thanks for reading

Tone