Limiter on masterbus?

[ensemble]

Hi guys,
Is it always advisable to put a limiter on the master bus to avoid clipping or is it just better to avoid sending individual tracks to loud to the master? The second is true for sure but anyway, limiter on master-bus?

I mix both in Ableton live and sometimes in Logic.

Cheers and happy x-mas!

ens

[Lagerfeldt]

Originally Posted by ensemble

Hi guys,
Is it always advisable to put a limiter on the master bus to avoid clipping

To the contrary. It's advisable not to put a limiter on the master bus during mixing. Leave that for the mastering.

A) There's no reason to "protect" the master bus by inserting a limiter, you simply lower the master bus as long as you observe the below rules, and

B) If you would like dynamic control on your master bus, a bit of wideband compression is usually a better choice, i.e. an SSL type glue compressor, but don't use it as a crutch.

If you overload the master bus and have a limiter plug-in like Waves L2 (just an example) inserted you will overload the plug-in internally. You can not control the amount of gain reduction if you're exceeding 0 dBFS on the master bus, even if you drop the master fader and it shows no clipping. Explanation continued below...

or is it just better to avoid sending individual tracks to loud to the master? The second is true for sure but anyway, limiter on master-bus?

In a floating point system like Logic Pro it does not matter if you output too loud to the master bus and then lower it - as long as you do not have plug-ins inserted on the master bus. At least not fixed point plug-ins or dynamic ones that do not have a floating point attenuation option on the input.

You can safely drop the master output level if you're overloading on the master. Lowering your individual faders or lowering the master bus will yield 100% identical results. Naturally you need to observe the internal overload rule for outputting or sending to an aux bus, e.g. when you're sum compressing your drums on a bus.

Please notice that when I'm saying "master bus" I'm talking about the Stereo Out (Output 1-2) not the separate "Master Fader" offset fader in Logic Pro.

I mix both in Ableton live and sometimes in Logic.

My experience with Ableton Live is limited but I remember it being very difficult to ascertain the metering overload values, though they are easily confirmed in Logic Pro.

[patrickg]

Originally Posted by Lagerfeldt

To the contrary. It's advisable not to put a limiter on the master bus during mixing. Leave that for the mastering.

True, but sometimes you just want to bump your work in progress, no? You can always take your limiter plug out...I just realized your quote says "during mixing"...it brings up a good question, where does composing end and mixing begin in electronica?

[alehoe]

your track should not clip the master with the limiter off ever

you can use your limiter for mixing though.. never hurt me

[Lagerfeldt]

Originally Posted by patrickg

True, but sometimes you just want to bump your work in progress, no?

If you want it louder, then turn up the volume. No need for a limiter in that case. If you want to test the dynamics or add mix glue compression, then use a compressor.

Once you add processing to the mix bus you're making mix choices based on what you hear. So it's usually a good idea to leave the mix bus compressor on during the final mix bounce if you applied it during mixing or the mix could change too much. Unless you've overdone it, the mastering engineer will prefer to at least have the compressed version as a reference. We're talking 2-3 dB of overall mix compression here, e.g. an SSL style glue compressor, etc.

The mastering engineer does not like to be presented with a brickwall limited mix bounce. So adding a limiter during mixing will not give you a realistic idea of the final sound and you could be making decisions based on the wrong premises while you're mixing. Instead you should limit your individual tracks, sum compress, sum limit, etc. That will give you a much more controlled mixed instead of the false security of a mix bus limiter.

Things aren't that black & white of course, but that's some of the logic behind why not to use a limiter, and especially since it does not protect your from internal clipping.

I just realized your quote says "during mixing"...it brings up a good question, where does composing end and mixing begin in electronica?

Now that's a good question. Depending on your workflow there are no borders.

[Tarkovsky]

One disadvantage of using a limiter is extra latency as they usually employ a look ahead.

[T71]

Uh huhuhuh, you said masterbus.

...Sorry, couldn't resist.

[triez]

Originally Posted by Lagerfeldt

In a floating point system like Logic Pro it does not matter if you output too loud to the master bus and then lower it - as long as you do not have plug-ins inserted on the master bus. At least not fixed point plug-ins or dynamic ones that do not have a floating point attenuation option on the input.

While this may be true in this particular case, I would not advise it for this reason - I think that a lot of the reason that digital music sound so brittle is because of massive mix build up. I would strongly advise anyone using any DAW to treat it exactly like an analog console - set your master fader to 0dB and never move it off that point, and use your channel faders to build a mix to sit under that point.

So often I see people mixing on DAW's with screaming hot channel levels, and a master fader pulled right down to compensate. People record too hot and mix too hot on DAW's, and use the master fader as a attenuator to pull the whole transient clipped mess down to a listenable level.

In a nutshell, what I am suggesting is that the art of gain staging is just a important in a DAW as it is in an analog studio.

[Lagerfeldt]

Originally Posted by triez

I would strongly advise anyone using any DAW to treat it exactly like an analog console - set your master fader to 0dB and never move it off that point, and use your channel faders to build a mix to sit under that point.

I agree that you should pay attention to gain staging but you're jumping to conclusions.

There's no loss or change in sound in a correctly designed floating point chain, so you can have your channels apparently clipping and your master bus down to compensate and get 100% identical result. No actual clipping occurs, no change of sound, no distortion, no loss of stereo image. It will pass a null test.

You will get in trouble if you're overloading fixed point plug-ins or any (dynamic) plug-ins without floating point input attenuation, so that's what you want to avoid.

So while your recommendation makes some sense from a practical point of view it's too drastic in my opinion and both simplifies the problem and the solution.

I think Cubase has an option for fixed point output on channel inserts, and that may cause trouble if you don't know what you're doing. But apart from that, sequencers like Logic Pro and Cubase use floating point all thru, except for the Bitcrusher plug-in in Logic Pro.

Let me add the solution for fixing an overloaded bus where you would like to use fixed point or dynamic plug-ins. Simply insert a floating point gain attenuator (such as the Utility > Gain plug-in in Logic Pro) as the first plug-in on the bus.

So often I see people mixing on DAW's with screaming hot channel levels, and a master fader pulled right down to compensate. People record too hot and mix too hot on DAW's, and use the master fader as a attenuator to pull the whole transient clipped mess down to a listenable level.

Agan, there's no change in sound as long as you follow good practices as describe above.

Recording too hot is another matter, no reason to push the envelope here. I recommend -6 dFBS peak at 24 bits.

I grew up on analog so I can't help pay attention to my gain structure while mixing ITB, so I'm actually using a workflow closer to what you suggested. Ironic isn't it. ;-)