Beat matching, mash ups & Audacity - Help please!

[CaptainDavey]

I'm currently playing around with Audacity and trying to mash some songs together, on top of one another (acapella's over beats and whatnot) for shits and giggles but I'm struggle to work out the BPM and issues regarding tempo. The acapella lyric is always too quick for the beat.

Any help at all would be greatly appreciated

 

[WinmarToLockett]

You're doing it wrong.

Software like "Mixed In Key" will give you the bpm of a track.

Abeleton Live will let you put it together in a cohesive way.

Youtube both of them and you'll be on your way.