Hello Mark and welcome to the Cow Audio Forum.
I honestly have no clue, but let’s see…..of course you may just be trying to reduce the background sound on your tracks, but Google Says…
Since Garageband does not have a real crossfade function (as most DAWs have) within a single track, to produce a crossfade, you can place the second clip on a new track. Then create the end-fade on the first clip with as many automation points as necessary to create the fade shape you want. Then fade in the second clip (on a new track), again using as many points as necessary for the fade-in shape you want. Then slide the second clip forward to create an overlap of the fade-in and the fade out curves. That will create a true crossfade without the clicks at the end and beginning of the individual clips.
For a true crossfade, the second clip must begin before the first clip ends.
Note: The end-fade volume automation reaches “0” before the first clip ends, and the fade-in does not start to rise before the second clip begins.
About raising the level. Headroom may be an issue. It’s better to turn dow the loud tracks until your already turned up is right.
You can try inserting an effect like a compressor in the individual track and use its makeup gain for more gain, if Garage Band will let you. Garage Band does have limitations that go away when you step up to Logic Pro X. And Logic Pro X has a LOT more functionality.
Regards,
Ty Ford
Cow Audio Forum Leader
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