How to graduate an increase in sound

I have a downloaded sound effect that I want to use for a radio play.
It fades in and runs for 10 seconds.
I know how to stretch the piece to run for a minute but I can’t fathom how to continue to graduate an increase in the sound from the end point of the original track for 50 seconds to the end of the stretched track.
I don’t know if it’s even possible. Can anyone advise me, please?
Thank you

Sure. Use the Envelope tool, two white arrows and bent blue line. When you select the tool, it will give you two blue “steering” lines in the timeline. They’re rubber bands and when you push them around, the sound follows them.


How do you intend to do that?
What sort of sound effect is it?

Hi and thanks
I’ve tried the envelope tool and not been very successful. I will give it another go.

I’ve stretched the track using Paulstretch. It’s a sfx of a rumbling sound which I’m using for a build up. After the silence of the eye of the storm, the rumbling starts low as the sea heads back to a lighthouse. The keepers are trying to bring an injured man inside from the parapet of the lightouse and can see the wave heading toward them. They are struggling desperately to get indoors before it breaks over them. It rises to a crescendo as crashes over the lighthouse and mixed with breaking glass etc.

Fingers crossed with the envelope tool. I will get the hang of it.

I’ve managed to make a change by mixing the same sound effect or layering it. That has increased the level. I also played with the envelope. Not sure it worked.

You gotta be doing something wrong. Attached, a simple fade out and fade in graphic. Attached, the resulting sound.


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