#1
I put in the track "Floods" by Pantera for the purpose of covering it with overdubbed guitar and what have you.

Here is my problem - No matter what I set the BPM/Metronome to, it DOES NOT ever sync up to the song. Even when I hold shift and drag the songs beginning to an appropriate point for it to sync up to every beat/measure.

Am I doing something wrong? How does one perfectly sync up a metronome to an already mixed/produced song such as a Pantera song like this? I've tried BPM's 59-65 and 115-125 and nothing syncs up.

I also hate how once the track is already in and you change BPM, the whole track changes speed, so I have to delete the track, set bpm, start trying again.
#2
I think that was recorded in analog and not played with a click, one of the reasons why Pantera were so good, they were really tight as a band and didn't need to track down to a click.

You can go in sections and try something like tap to tempo and see if it first. I'd say look for hits on the audio file where there is a kick and snare, that'd should be your 1 and 2 or 1 and 3, depending on how it is played.

Look up this Reaper Tempo Mapping tutorial:
http://www.soundonsound.com/sos/mar11/articles/reaper-tech-0311.htm
#3
Thank you sir I shall mess around with this function. I'm trying to get more and more used to Reaper, depending on how patient I am.
#5
I've noticed that if you adjust the tempo of a song AFTER you've imported a track it gets weird. try setting the tempo to the correct BPM in reaper before you drag the mp3 in (assuming that's how you're doing it)
#6
To fix it speeding up and slowing down I've found that right clicking the stem and going to Item Settings -> Set Item Timebase to Time works pretty well.
But yeah, trying to sync to songs that haven't been recorded to a click is a pain.
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