Volume Reducing

You only get volume loss if you turn them down.  However, adding tracks will naturally mask some of the intro sounds

If you are simply running each track at 0 dB, full fader or whatever, most of the time you just get a mess.  Setting faders is step one of mixing.

First, lower all your faders to -6 dB to -12.  As you add more tracks or instruments each fader will need to come down a little, so figure out how many you have and pull down your faders appropriately.  I'm sure someone has figured out a formula, but it is also an artsy, feel thing.  Just keep in mind doubling the volume = 6 dB, so two tracks can come down by that much and it will sound as loud as either one at 0 dB.

So the real solution to your guitar solo intro "disappearing" in volume when the rhythm section enters is to have your guitar at full fader and then pulling it down through automation when the rhythm comes in, but the rhthym has to be mixed at a much lower volume level - say a drum sub mix at -12 dB and the bass at - 9 dB.  The guitar fader starts at -4 dB and fades down when the rthym comes in to -9 dB, so all those tracks "mixed" together output at - 6 dB.  These numbers are for example only, of course, but the technique is one way.

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