This is something I'm pretty familiar with. I work in a major market and have all the tools you could ever want (including ProTools) and yet, when it comes to beat mixing, I will only use CEP. Here is the most accurate way I have found to do this. It seems long and complicated, but if you follow the instructions, after you do this once, it's easy.

1. Get a beat bed from your imaging CD and a file you want to match to it. Have them both loaded and open, for easy access.
2. Make sure they are compatable time signatures. Obviously, it would be very hard to match 3/4 time with 4/4 time. I like to do everything in 4's. Keeps it easy. So, for the sake of this post, let's assume your beat bed is in 4/4 and so is the song you're matching to the bed.
3. Start with your beat bed active in the edit view, not the multi-track. Find the beginning of a musical phrase. Make sure you start with beat 1 and not a pickup note.
4. Begin highlighting a 32 beat phrase. (You can also use 16, but 32 will give you a more accurate match). You will have to count beats in your head and use your ears. This gets easier the more you do it. You know you've got it just right when you loop the section and it's seamless.
5. Once you have found the 32 beat phrase, look at your selection time. Write it down. Let's say it's 15.382 seconds.
6. Switch to the view of the song you want to match. For instance, we'll say Britney spears is what you want to match. In the Britney file, repeat step 4. Find 32 beats and you'll know it's right when you have a seamless loop. You'll want to use songs with similar beats...at least a little close, so that you're not severely changing the speed. Let's assume that Britney's 32 beats are 17.885 seconds. You will need to condense that time to 15.382, to get a perfect beat match to your beat bed.
7. Go into effects/time-pitch/stretch. Make sure you have it set to do a tempo change and preserve the original pitch. There is a textbox where you can type the desired length. With the Britney file open, and the 32 beats highlighted, type the desired length as 15.382. DO NOT PROCESS THIS YET!
8. The window should display a ratio. Write it down.
9. Close the window and highlight the entire Britney file.
10. Re-open the stretch function window.
11. Type in the ratio that you have written down.
12. Process the cut.

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