Reaper revisited after 7 years fallow

[Chipotle]

Originally Posted by unimogbert

Oh you already did, input gain in the lookahead. Why would that be added if reducing dynamic range didn't make it quieter?

Because that's the way that particular plugin works. As you've discovered, they are different. Some just automatically add makeup gain regardless. Some may not have makeup gain at all. Some have a setting to add it or not at your preference.

I don't think the issue here is that nobody understands how compression and limiting work. I think it's about the behavior of plugins, and each is different. We can all be "right", you know.

[unimogbert]

Some may not have makeup gain. OK. My plugins don't act that way but I believe you.

Now, you know how to use a wide variety of devices and plugins. That's good. I don't. I'm learning. I asked a question and was fed incorrect information and bluster when I asked for an explanation.

What is being told to newbies by people who should know better is flat out wrong.

Reducing dynamic range does not make anything louder. Twisting a knob on a Limiter probably does (as observed).

Limiters and Compressors generally have some gain function included or available because reducing dynamic range makes things quieter. Why else would the gain function be included.

A Limiter apparently might not show you a gain control but because it's designed as a Limiter there most likely WILL be gain in it. Thus loudness goes up. I have no argument with that.


If you tell an audio engineering student that reducing dynamic range makes things louder you'll foul them up for a large part of their career until they figure out you were referring to knob-twisting rather than what's actually happening to the signal. Some might never figure it out and will pass the myth on to their acolytes as an absolute truth.

I'm getting a sense of what Galileo went thru challenging the accepted explanations for things....... fortunately I can only be virtually burned at the stake for this heresy and not IRL. (banning isn't unexpected though)

[AcousticDreams]

Here is my novice explanation. It may not be entirely correct, but it is the way I have always looked at it.

The Audio wave form has, the Top of the Peak, and the bottom of the Valley.

Here is a Completely Imaginary example of fictitious values.
In an Unprocessed signal:

It you turn up the Peak level to an X db ( Lets say that X simply represents the loudest decibel level at which you can tolerate the music, before it begins to disturb, hurt your ears. Think of that audio peak like a knife blade. Digging into you ears) In unprocessed music your valley might then be as low as X - 70db. There is a 70 db difference between the top of the Peak, & the bottom of the Valley. Hope that makes sense.

In a Processed Signal:

When you Limit or compress a signal you are reducing the Dynamic range. So now the difference between the Peak & Valley might now be reduced to X- 20 db. Effectively you have reduced the 70 db range, to only 20 db difference between the top of the Peak and the bottom of the valley.

Now with your newly processed signal with less dynamic range, you can now realign your level back to the X value ( the loudest you can listen to it) But now your Valleys are more easily heard because the range difference is less. When the difference between Valleys and Peaks are vast, it is harder to hear the bottom of the valley when you are listening at low levels.

So yes, compressors and limiters function on its own are not turning up the loudness level...they are simply reducing the dynamic range. Reducing the dynamic range lets you turn it up to your X value. Remembering that in this case X represents the loudest decibel level in which you can turn up the Peak.

Some compressors and limiters have an automatic function that adjust level.

But in reality it is as Duplemeter said a " perceived loudness increases "

Again, words, formulas still sometimes do not completely explain all principles to the fullest.

To add one last description...lets say that X was not the loudest you could listen to the music...but in fact a medium value for soft easy listening pleasure. But with a processed signal, and the dynamic range reduced, you might be able to turn up the X value higher so that you can now hear the Valleys better.

[Gordon Currie]

With all the purported 'engineers' here, I am amazed that no one has referenced the AES (Audio Engineering Society) - a 75 year old standards organization - for definitions.

From the compressor entry:
"A signal processing device used to reduce the dynamic range of the signal passing through it."

Makeup gain is not required to have a compressor circuit/process; it is a utility add-on that makes it easier to use in certain cases.

https://www.aes.org/par/c/

[Chipotle]

Originally Posted by unimogbert

Some may not have makeup gain. OK. My plugins don't act that way but I believe you.

Many have a switch for makeup gain that is ON by default. Having no makeup gain is probably a rare case; if it isn't configurable, then chances are it's ON.

"A signal processing device used to reduce the dynamic range of the signal passing through it."

Makeup gain is not required to have a compressor circuit/process

The technical definition of a compressor doesn't define how a particular plugin will work, though. Tbh, I fall on unimogbert's side as I don't think a compressor--at least, the actual compression part--makes things louder...

but COMPRESSORS (and compressor plugins) DO make things louder.

Maybe that's the distinction we're discussing here. As I said, I don't think anyone on this thread misunderstands what compression is, in the end.

[unimogbert]

I checked the AES definition for Limiter and it also does not address makeup gain. (I was unaware of this resource)

I agree that everyone arguing here probably knows how to use Compressors and Limiters. Some way more than others (me).

That's not the same thing as being able to explain what's inside.
This doesn't matter in application.

But it mattered to ME when I asked why and got misinformation in response.

Thanks to those who have gently tried to explain what you know.

[DupleMeter]

Originally Posted by unimogbert

If reducing dynamic range increases loudness then explain why setting a compressor for a very high ratio then pulling the threshold down makes the track quieter.

A limiter is a very high ratio compressor, is it not? That's what all the YT experts assert.

If you pull the compressor down, it gets quieter.

If you pull a limiter down, it gets louder.

I'm not asking how to use it. I'm asking why it does that?

Compressor gets quieter. Limiter gets louder. Tell me what's different.

Oh you already did, input gain in the lookahead. Why would that be added if reducing dynamic range didn't make it quieter?

Let's start with that last comment: you seem to misunderstand lookahead as a function in plugins. Lookahead is merely a function in digital that allows the limiter to prepare for whatever is coming by looking at the incoming signal a few milliseconds before it arrives. It has nothing to do with gain. It's all about the plugin reacting to peaks in a way that no peak will ever get past the detection circuit.

So, your confusion on the loudness issue seems to be because you are referencing limiters that are auto adjusting threshold & ceiling, which will give them the appearance of acting differently than a typical limiter or compressor, but they are simply taking away some controls & auto adjust them.

So, a typical limiter will have a ceiling setting that sets the maximum peak level of the signal & a threshold setting that, when set to the same value as the ceiling, will limit without added gain. As you lower the threshold you are effective adding gain at the input stage to drive the limiting harder. This makes things louder.

You can get the exact same results from a compressor by increasing the input gain into the detection circuit, but now we have similar setting with different functions. A compressor's threshold acts more like the limiter's "ceiling" setting, only it isn't a hard ceiling because a compressor has a ratio less than infinity:1. Some older compressors have a fixed threshold and have input & output controls (e.g. the 1176 Limiting Amplifier) or gain & peak controls (e.g. the LA2A).

The auto gain feature you are experiencing is not common to all limiters. When you have a limiter that does, it falls into the "maximizer" category. Unfortunately, those types of limiters can add crazy amounts of distortion. So, really, "maximizers", which are a subgroup of limiters intended to maximize loudness, but they do not represent all limiters...it's the "all thumbs are fingers, but not all fingers are thumbs" scenario.

So the TLDR; is - you're getting confused by the auto-gain feature of some limiters. It's not even on most limiters. Just the "maximizers".

Hopefully that helps clear things up. It can be confusing, especially if you don't have a background in engineering or have any real world experience with the hardware that these things are trying to emulate.

[unimogbert]

Thanks but I'm no longer confused.
I have a rather deep background in Electrical and Nuclear engineering so I'm capable of understanding quite a lot given accurate information on new things.

It was that 'reducing dynamic range makes it louder' statement way back in the thread that caused the confusion.

Was there a knob labelled that way long ago which created that myth?

[DupleMeter]

Originally Posted by unimogbert

Thanks but I'm no longer confused.
I have a rather deep background in Electrical and Nuclear engineering so I'm capable of understanding quite a lot given accurate information on new things.

I meant Audio Engineering...but electrical engineering does help when you deal with real hardware/analogue