Remixing

how do i put a beat over an acapella and make it sound on beat?

what media are the beat and vocal??? if its all on your mpc your gonna have to tune them.... maybe cut up the vocal and fit it to the beat.... i like to just use vocals off records and play them over the mpc... its easier to match it

both r wav files on my computer

Throw them in a sequencer or merge them in your audio editor.

When working with .mp3 acapellas and instrumentals I use ACID Pro. Export to .wav, chop it in Recycle and load it into the MPC.

When working on mixes like this, it's all dex.

Use a multitracker, cool edit pro, VEGAS (what I use). Put acapella on one track and beat on the other. You can drag and slide the files around
until they fit with each other.

when using acid pro i load up the vocals and get the BPM
so if its 85 BPM i jump on the MP and make a beat at that
tempo so it matches off top