Basic questions from a n00b

I have about three guys for whom I 'mix' piano.
Might sound silly to those who know, but to those guys I did something magicy and the out sounded better than the in.
I'll take it! ;)

Ya always want the 'out' to be better than the 'in'........I do so much piano that I guess I take it for granted that anyone can mix it.....I have my little piano pathway that I use for the most part and it doesn't fail.............However...TRACKING piano. Different animal entirely.
 
It might sound like a technicality but say you were to use a downward compressor, as you describe, to raise ambient noises on an extremely dynamic operatic performance,
you're going to mangle the upper dynamics of the performance in order to get your result,
whereas an upward compressor get the result and preserve the dynamics of the performance.
Naw. Either way it depends on threshold, ratio, attack and release Knee, and all the other parameters how "mangled" things get.

Mathematically, it's exactly the same thing. If you built them side by side in digital where everything all variables are completely under your control, and set them exactly the same, they will give exactly the same output and if you invert one of the signals they'll null perfectly. You could come really close in analog too, but of course there is more slop and less granular control and if the circuits are significantly different they may not be quite as mathematically identical.

Now, it may be true that actual real world upward compressors are generally designed in such a way that they will "mangle the upper dynamics", but I honestly can't think of any of these devices that aren't built into guitar pedals. Guitarists are weird and pedal designers are even weirder, and those things were definitely not designed to maintain the delicate dynamics of a vocal or detail of a drum performance. So, like, in analog practice you're probably right, but in general theory it's not actually true.


Edit - Kinda funny because the first example of compansion that comes to my head (if dolby nr hadn't already been mentioned) is also in a guitar pedal. Digital delay pedals usually have a monolithic compander chip in them. It's basically a compressor and expander in one little box, each with its own input and output, but they apply opposite gain curves. The input signal gets mixed with the feedback signal and then compressed before going into the ADC and memory buffer then (a while later based on delay time) out the DAC and then it gets expanded and mixed with the current input signal. This is for a couple reasons. 1) The digital part can handle 3, maybe 5 V, but most guitar pedals can get up to 6 or 7. B) It gives better fidelity with fewer bits, and compared to like opamps and resistors, bits ain't cheap.
 
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Something acting on audio below a threshold will not impact upon audio which exceeds the threshold.
The reverse is also true.

They are fundamentality different approaches and, to the best of my knowledge, the example I gave illustrates why.

edit : from wiki
Screen Shot 2017-10-08 at 17.46.56.png
 
Well that picture shows that the upward leaves everything above threshold linear, so which one is doing the mangling? ;)

But that's also not really the way it works. In most cases it does nothing to the signal below threshold except add a set amount of gain. Above threshold, that gain is reduced. In that sense it is actually still "acting on" audio above threshold. In fact, it's more (well, more exactly) like adding gain before a downward compressor than adding makeup gain after.
 
Well that picture shows that the upward leaves everything above threshold linear, so which one is doing the mangling? ;)

But that's also not really the way it works. In most cases it does nothing to the signal below threshold except add a set amount of gain. Above threshold, that gain is reduced. In that sense it is actually still "acting on" audio above threshold. In fact, it's more (well, more exactly) like adding gain before a downward compressor than adding makeup gain after.

It doesn't leave everything above the threshold 'linear'. It leaves it alone.
An upward compressor, by definition, affects signal below threshold.

Your description, again to the best of my knowledge, is the misconception.

If you have a comp that acts as you describe, regardless of how it's labelled or marketed, it's a downward compressor with makeup gain.
 
Sadly, no.
I have about 10 plugs which do 'upward compression'. None of them actually does.
They all either do what you described, or upwards expansion.

As we know from our "phase" switch - Just because the label says so, doesn't mean it is so.
 
There are some pretty famous and widely used compressors which can only apply so much gain reduction, so beyond a certain point the "open up" and head back toward 1:1 ratio. There's like a kink in their response which can be interesting. Kinda why there are so many emulations of them and the good ones sell for real money. ;)
 
I'm guessing his absence may be related to the responses received. He did say he didn't understand anything he's read thus far...and I don't think any of the above helped. It's not a "problem", it's just head shake worthy. Carry on.
 
It may be more to do with the first responder telling him to go to youtube.
We each shake our head at different things.
 
It may be more to do with the first responder telling him to go to youtube.
We each shake our head at different things.

Well, he's having trouble reading and understanding...so why not try watching and understanding. The goal is getting him to understand, not just to be on the site.
 
a) I've never heard or of seen an "upward compressor". Can someone send a link to such a plug-in? And if it is not a common plug-in (not in my Waves Gold bundle), why are we even talking about it, especially in a noob thread?

b) it appears that if such a thing exists, it mangles the softer half of the signal, smashing the softer portion of the delicate part of a vocal in exchange for preserving the dynamic curve of the screaming peaks. Is that actually desirable, and if so, in what use case? I've never heard one, but in my mind, it is not sounding very good.
 
a) I've never heard or of seen an "upward compressor". Can someone send a link to such a plug-in? And if it is not a common plug-in (not in my Waves Gold bundle), why are we even talking about it, especially in a noob thread?

They're not very common at all, although plenty of manufacturers seem to throw the description around erroneously.
I wasn't aware of that until this thread.

b) it appears that if such a thing exists, it mangles the softer half of the signal, smashing the softer portion of the delicate part of a vocal in exchange for preserving the dynamic curve of the screaming peaks. Is that actually desirable, and if so, in what use case? I've never heard one, but in my mind, it is not sounding very good.

It'll no more mangle or smash than a downward compressor. Your ratio dictates that.

If you want to increase ambience, breaths, talking, whispering without altering the natural sound of louder content, that would call for an upward compressor.
I wouldn't be surprised if they used them in orchestral or operatic recordings, although I don't know that for sure.

Heh, Look on GS or similar for threads called "recommend an upward compressor"
Even there you'll have 20-30 posts from guys saying 'did you mean downward compressor/ny compressor/upward expander/expander/downward facing dog/toaster/spandau ballet record', before you find someone who knows what it is.
 
I would check out the mix engineers handbook. That's a great resource. Also like many others, YT is a great source for knowledge. They also have some online coruse's from Berklee and other schools you can take. So many ways to learn to day, the only thing I seem to lack is time to focus and learn. ha
 
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