Ok Experts-why is the wav getting smaller? it didnt in 1.5

Question

ok experts-quick questions
in adobe audition 1.5 in multitrack one i would add an instrumental of a beat
on multitrack two i would record my vocals
when i saved these together the song wave would look like it should-with it slightly bigger than the orginal instrumental on multitrack one
because it now had that plus the vocals added to it
well now on audition 3 - when i save the vocal with the instrumental-the final wav becomes much much much smaller than the original
multitrack one instrumental.
Does anyone know why this is?

Answer 1

>...just curious much like the time I was hitting that hornets nest to see what was inside...
Okay, to perhaps satisfy a bit more of your curiosity, here's the panning hornet's nest (modified from my original version, which I finally discovered, and with a bit more information):
So what happens if you pan mono signals to the centre of the stereo sound field? Let's just consider loudspeakers, as this is the most common requirement to get right.
To get a result that sounds as loud in the centre as it does at the edges, in terms of electrical adding of signals, you need to have each side of the stereo signal outputting half of the voltage - and this would imply that the pan pot should drop the level of each signal 6dB, and not 3dB at all, like the only option we have in Audition. But, in a normal room, with a reasonable degree of reverberation, it's the  acoustical power of the summing signal in the centre we have to consider, and it's this implies that a 3dB drop is what's required - and this is pretty much the only reason that we have it set as it is. But it's more complicated than that; with loudspeakers you get mutual coupling below about 100Hz - and this augments the power coupling by about 3dB... which I'll return to shortly.
And there's more. If you record a voice talking, and pan it across the sound stage in stereo with a -3dB drop in the centre, you will get a voice that moves across the field at the same perceived level all the way. But if you reduce the result to a mono signal, you will get a 3dB rise in the signal level as the speaker passes the centre (only now it's in mono, so you can't tell) - and that isn't right at all. This means that in practice, any mono listener to a radio play recorded in stereo is going to get level differences that were not intended.
I don't think that anybody ever does what I'm going to mention next, but if you did, you'd realise the other problem here, and that would be the effect on a bass guitar if you panned it. With this, you get more LF when it passes through the centre position, because of the mutual coupling effect below 100Hz, so that's not good either (but you are going to get a degree of this, whatever you do, in fairness). So now, the pan pot has altered the EQ as well! 
And it's all of these considerations that tend to cause manufacturers to compromise on 4.5dB as a centre-drop - because at the worst, over most of the frequency range, you are only going to get a 1.5dB error. But this is arbitrary; to a degree, the amount of effect you get from this is room and speaker dependant, and it also varies with the distance apart of the speakers. And it's different again with headphones, just to make it even  more confusing!
I should mention, before anybody points out that in an anechoic space, the acoustic sum on the centre plane of the speakers is the same as the electrical sum, that I'm aware of that - and just how many people do you know who monitor under these conditions? Virtually all normal spaces will acoustically couple the bass end, but most significantly, the aforementioned condition only really holds true for anybody positioned absolutely centrally between the speakers.
So I'd say, one way or another, that there are good grounds for having rather more options available for the panpots than we have at present. And yes, this really is a can of worms.