Topic: making matrix/mixes help please

[rattyraiz]

i have no problems making them just have a few questions. im using samplitude for aud/sbd mixing and time stretching if needed. anyway my question is this: am i correct in saying the volume control is the only option for mixing percents? i have gone strictly by ear with the volume controls but i would like to know exactly what ratios im getting or percents. like say i keep sbd at 0db and move aud up to 2db. i guess im just wondering mathematically how you can tell what amount of each recording is actually getting mixed. thx in advance

[Brian Skalinder]

I can't answer your question, but...why does the specific ratio matter as long as it sounds best to your ears?

[rattyraiz]

well its more for the information. plus if i wanted to ideally make a true 70/30% ratio it would be nice to know the exact settings to achieve that.

[Brian Skalinder]

The information bit I get, but I don't understand how you would know - before listening, or in lieu of listening - that you wanted a 70/30 mix.

At any rate, I'm no help, so I'll STFU now.    Hopefully someone can answer your question...

[rattyraiz]

ya i guess in the end im just interested in what exactly im making

[dklein]

You can run an analysis on each file to determine the average level in dB.  Then adjust those numbers based on how you've mixed to figure out the relative difference in dB.

e.g. board has avg. level -15dB and you mix it straight
       aud has avg. level -12dB and you mix it +2 dB

relative difference in sources is the difference between -15 and (-12+2) = 5dB
Then you either whip out your log formulas or you can cheat by going into something like CoolEditPro, and take any section of music and pull up the amplitude adjustment, set the 5dB and then uncheck the little box that switches between dB and %.  That will show you the equivalent percentage for a dB difference - then do the math.

In the above example, the board signal that is 5dB lower is at 56% of the board so you're mixing at  56/(100+56) = 36%
Then the aud is 100/(100+56) = 64%

So it's 64/36 (aud/board)

To save you the math - here's the scale in 1 dB increments (look up the net difference between the two sources, using average level before mixdown and adjusting for whatever you did to it when mixing).

difference
Same (0dB) = 50/50
1dB = 53/47
2dB = 56/44
3dB = 59/41
4dB = 61/39
5dB = 64/36
6dB = 67/33
7dB = 69/31
8dB = 72/28
9dB = 74/26

or put the other way
50/50 = 0 dB
60/40 = 3.5 dB difference
70/30 = 7.4 dB difference

[rattyraiz]

awesome thank you for the wealth of info