Levels in mixing

[popsaka]

My question: After all these years, I'm just now noticing, when reviewing a
mix, how an instrument's level becomes substantially louder when there are
fewer active tracks simultaneously opposite it (?) Is it just me... has my hearing suddenly become more selective... or is this quite normal?
For the record, I'm using a very old version of Orion (which I luv, BTW) so
its not like I'm skipping through various DAW's...
...oh, and this lovely phenomenon doesn't show on the different level/VU
meters either...
It's as if the available loudness window is getting automatically filled
Cheers folks and thanx in advance

[Mushy Mushy]

Let's use an analogy.

Take a bucket and throw a big sponge in there. Then put another big sponge in there and it simply won't fit. Both sponges will have to compress (poor choice of words given the subject matter) to fit in the same space.

However if you carefully place the first sponge in the bucket whilst leaving room for the second they'll both fit.

In audio terms this space is created by careful panning, EQ, audio compression and of course the track levels themselves.

[RockinMillie]

It's all about proper gain-staging:

http://blog.kimlajoie.com/the-most-powerful-tool/

* Should not this thread be in the 'Production Techniques' forum ?

[protrackmastering]

Because less channels in the mix means less frequencies fighting between each other. As a result of this you can get a louder master.

[Tux]

Yes as the other contributors have pointed out, it's all a matter of physics.

So I'd like to bring the matter back 'on topic' if I may considering this question should have really been posted in a different forum.

What version of Orion are you using? Platinum? I too am an Orion user and for a very long time stuck to an old version. It seems to have that effect on you where you get comfortable with it like an old pair of shoes. I sometimes wonder if mine and others reluctance to keep up with the upgrades was partly responsible for Rich mothballing the project?

However, if you are a licensed user I urge you to upgrade to at least v8.02. It's wroth it for the better GUI, and the Pro 9 virtual 909 is awesome. I took the plunge recently and I'm glad I did.

Although Orion is technically dead Rich hasn't ruled out bringing it back one day, but right now it's at the point where I'm happy to wait.

[popsaka]

Thank you all so much for your replies... However I discovered what was happening...
At the moment I'm limited to the on board Realtek (stuff?) and in the Realtek control app I foolishly enabled the
loudness/contour option and "DOH!" it turned out that being global it was 'auto-leveling' everything! (:-b)
...who knew?

[LawrenceF]

Figured as much, that it was a limiter.

That's what happens when you limit and the master limiter is adding X db of gain, then when the drums or something else that was previously also hitting the limiter drops out, everything else still playing gets louder.