limit or compress

[Stinkfoot]

i have a limiter/enhancer & soon will have compressor/sustainer......question is ..either or ?...is there any point to using both..? & if so which 1st in the signal path..?

[51m0n]

There is definitely a point to using both, they do very different things....

Set 'correctly' (that is how they are designed to work) the limiter is there to just catch the peaks of the most over enthusiastic moments, and as a speaker saver, just preventing the highest peaks from ruining a performance. The threshold and the ratio are high, the attack and release low.

A compressor is a more general dynamic and envelope sculpting tool, more often than not it has a much lower threshold and ratio and a longer release and attack (although the attack and release would still be short by compressor standards when dealing with a bass as input, the attack and release on a limiter are often far far faster than on a compressor). The compressor smooths out more general volume/dynamic differences a bit, and can also thicken up your sound as a result.

I'd put the limiter after the compressor (thats the norm), bt exactly where in the entire chain you have you want to put them I couldn't hazard a guess....

[escholl]

Ignore my previous edit. Run comp, then limiter.


I had read somewhere, it should be the other way, and it had made a lot of sense -- but until I can source that info, do it the conventional way.

Edited June 23, 2010 by escholl

[Jean-Luc Pickguard]

I'd have thought that a compressor would negate the need for a limiter most of the time. At most settings, while its compressing its also limiting isn't it?.

I'd use one or the other. I've tried lots, but my cheapo green behringer limiter pedal does what I need.

[51m0n]

[quote name='Jean-Luc Pickguard' post='875988' date='Jun 23 2010, 11:08 PM']I'd have thought that a compressor would negate the need for a limiter most of the time. At most settings, while its compressing its also limiting isn't it?.

I'd use one or the other. I've tried lots, but my cheapo green behringer limiter pedal does what I need.[/quote]

Well no.

Typically a compressor has a slower attack, deliberately to allow the front of the waveform through, keeping the bright attack to the sound.

This is great, but as you crank the make up gain, you also crank that peak, until it is always clipping you input.

At this point you need a very fast limiter to take a couple of dB off that peak to allow you to continue to bring your make up gain up.

Its really easy to show this with decent metering on a combined rack comp/limiter (like my compounder).

[escholl]

[quote name='51m0n' post='876013' date='Jun 23 2010, 11:32 PM']as you crank the make up gain, you also crank that peak, until it is always clipping you input.[/quote]

At that stage, could you not lower the limiting threshold to prevent that, if the limiter were first in the chain?


I swear that at some point I learned it was better to go limiter, then compressor, but I can't for the life of me remember where or find the info, it was probably in a book somewhere but I'm worried now that I've just made the whole thing up lol...hence my edit above.

[51m0n]

[quote name='escholl' post='876052' date='Jun 24 2010, 12:59 AM']At that stage, could you not lower the limiting threshold to prevent that, if the limiter were first in the chain?


I swear that at some point I learned it was better to go limiter, then compressor, but I can't for the life of me remember where or find the info, it was probably in a book somewhere but I'm worried now that I've just made the whole thing up lol...hence my edit above. [/quote]


No you cant. Because you've set the attack nice and long to allow the leading edge of the note through, giving you maximum punch.

Remember the attack is the time AFTER the threshold is crossed that the compressor engages. So if you set that long enopugh to allow the attack through, crank your ratio and dip you threshold to get a really nice pumping compression, once you wind up the make-up gain then if you' over hit' a note you will get a massive spike just before the compressor kicks in. Thats when you need a limiter, to catch those, nothing else.

Even if you dip the compresor threshold more it doesnt make any real difference since the attack is wide enough to mean the that leading edge is nolonger being caught (deliberately) by the compressor.

[escholl]

[quote name='51m0n' post='876139' date='Jun 24 2010, 09:11 AM']No you cant. Because you've set the attack nice and long to allow the leading edge of the note through, giving you maximum punch.

Remember the attack is the time AFTER the threshold is crossed that the compressor engages. So if you set that long enopugh to allow the attack through, crank your ratio and dip you threshold to get a really nice pumping compression, once you wind up the make-up gain then if you' over hit' a note you will get a massive spike just before the compressor kicks in. Thats when you need a limiter, to catch those, nothing else.

Even if you dip the compresor threshold more it doesnt make any real difference since the attack is wide enough to mean the that leading edge is nolonger being caught (deliberately) by the compressor.[/quote]

Ok, so, to satisfy my own curiosity, I had a bit of a play around this afternoon with a previously recorded bass guitar track. Used a Waves L1, Waves RComp, and an Algorithmix TTDR meter for the metering.
I then set RComp to 50ms attack, 200 release, ratio 3:1.

I found that putting the limiter after the compressor did indeed allow the large spikes through the compressor, boosted by the make up gain, and then limited by the limiter, as expected. However, the largest signal peaks would overload the input and especially the output of the compressor before being limited, not an issue really with the headroom on DSP plugins but would definitely be an issue with physical circuits.

I then tried it the other way round, so limiter, then compressor. The limiter threshold now had to be set a bit lower, to prevent the final output from clipping, BUT it did so without clipping the compressor at all either. It could be driven just as hard now, but without any stage clipping at all. To my ears, it also sounded more natural and smoother overall, but that is probably subjective.

So, either is effective, but for me I think I will stick to limiter, then compressor.

[Stinkfoot]

All very helpfull comments,lots to think about,.....thanks guys

[essexbasscat]

Come to the London bass bash, the topic will be discussed there 11.30 to around 12. 15 or so

T

[51m0n]

[quote name='escholl' post='876826' date='Jun 24 2010, 08:41 PM']Ok, so, to satisfy my own curiosity, I had a bit of a play around this afternoon with a previously recorded bass guitar track. Used a Waves L1, Waves RComp, and an Algorithmix TTDR meter for the metering.
I then set RComp to 50ms attack, 200 release, ratio 3:1.

I found that putting the limiter after the compressor did indeed allow the large spikes through the compressor, boosted by the make up gain, and then limited by the limiter, as expected. However, the largest signal peaks would overload the input and especially the output of the compressor before being limited, not an issue really with the headroom on DSP plugins but would definitely be an issue with physical circuits.

I then tried it the other way round, so limiter, then compressor. The limiter threshold now had to be set a bit lower, to prevent the final output from clipping, BUT it did so without clipping the compressor at all either. It could be driven just as hard now, but without any stage clipping at all. To my ears, it also sounded more natural and smoother overall, but that is probably subjective.

So, either is effective, but for me I think I will stick to limiter, then compressor.[/quote]

Hmmm according to the manual the Wave R-Comp has a built in L1 style limiter built in to the output, so its not the right tool to use to play with this, as its trying to automate this for you. ANy attempt to push it hard enough to emulate what I'm sayiing and you will be distorting the output.

Try Reaper's Reacomp compressor instead...

Comp then limiter is the norm in most of the dual function compressor limiter rack units I've ever seen, certinaly how its set up on my focusrite compounder, and I can easily get compression to light up, push a bit harder and push the limiter into action with the peak, without any amount of distortion from overloading the circuit. I can cause this to occur without pushing the input hard.

It will always be easier the other way around to not get any overs if you think about it, but you wont get the same extreme effect on the front of the note, this is certainly not an example of 'transparent' compression

Edited June 24, 2010 by 51m0n

[escholl]

[quote name='51m0n' post='877004' date='Jun 25 2010, 12:04 AM']Hmmm according to the manual the Wave R-Comp has a built in L1 style limiter built in to the output, so its not the right tool to use to play with this, as its trying to automate this for you. ANy attempt to push it hard enough to emulate what I'm sayiing and you will be distorting the output.[/quote]
Right, well, the point is that if it's clipping the built-in limiter, it's going to clip any output stage -- only with the possibility of distortion. In this sense the RComp works perfectly fine. It might not be the conventional way, but really, try it, it works very well.

[51m0n]

[quote name='escholl' post='877045' date='Jun 25 2010, 01:41 AM']Right, well, the point is that if it's clipping the built-in limiter, it's going to clip any output stage -- only with the possibility of distortion. In this sense the RComp works perfectly fine. It might not be the conventional way, but really, try it, it works very well. [/quote]

I dont think I explained myself very well.

That compressor is automatically designed to do what I am suggesting on its own.

You wont gain anything by putting a limiter after it, since it already limits at 0dBfs anyway.

Except maybe to get the limiter firing up earlier so you have a little more headroom for limiting to occur in.

It is in itself an example of comp-> limiter.

The point is limiter-> comp changes the envelope of the signal hitting the comp, which wil lchnage the action of the comp. Its not wrong (nothing is) and if it sounds good to you then great, use it. Its just another validation for using a limiter and a compressor together.

All I was trying to say is that the typical usage of a comp & limiter is comp first (*just like in the waves R-Compressor*), since the limiter stops overs caused by lifting the make up gain with a long attack time.

If you hit a built in limiter you WONT clip the output stage, you will limit the output at the threshold set for the limiter (or very close to it) - that is the point of the limiter.

You can mimic this with two seperate devices too, but you can never get the gain after the compressor higher than the clip point, however you can raise the gain after the limiter if you lower its threshold, which effectively achieves the same thing.

Does that make more sense?

[xgsjx]

I don't use a compressor or limiter, but I would have thought that if you run any effects after your compressor then the limiter would be best placed at the end of the chain to catch any spikes?
But then i suppose like any pedals, it's down to what [b]you[/b] like the sound of that counts.

[51m0n]

[quote name='xgsjx' post='877329' date='Jun 25 2010, 12:55 PM']But then i suppose like any pedals, it's down to what [b]you[/b] like the sound of that counts.[/quote]

+1 Absolutely!

[cheddatom]

I like limiters after compressors. You can use the compressor with a longer attack time to give a proper punchy sound, but then tame the peaks with a limiter. If you tame the peaks before the compressor, I would imagine you wouldn't get the same punch, but TBH i've never tried it.

[escholl]

[quote name='51m0n' post='877192' date='Jun 25 2010, 10:19 AM']Does that make more sense?[/quote]

I knew what you meant, I think I'm the one who didn't explain myself very well. It's ok, as you say either way works -- I was really just playing about to satisfy my curiosity. Besides, that focusrite unit you've got there is one of my personal favourites, so, it must be doing something right!