Many years ago I had the pleasure of performing at the Magic Castle. It was an awsome time. I performed on the large stage. While back stage, watching others perform, I kept an eye on the stage manager and his responsibilities. One of them included playing the background music that other performers had for their performances. I noted that hes was having quite the time with this. The main reason was because some of the performers who used different songs in their routines, had the songs on different tapes. (Tape cassetts were the thing then). I noted that at one point he was confused as to which tape, when and when to stop the music.
I have seen this affect the performer as well. When the music did not change when it was supposed to, or took too long to change, it threw the magician's timing off.
So giving this some thought I submitted an article to Genii Magazine about Music and Magic. I would like to highlight just a few of my thoughts here. If you would like the complete article, I can tell you which Genii volume to look for.
So, to begin with, the solution to the problem of different songs on different tapes/CD's is to put them all on one. Ok, fine. However performing with music is much more than having it in the background. Having it play in the background can at times be ok. However on the stage, when there is no talking, the music must become part of the magic. The music must be suited for the illusion. For example "Tea for Two" would not be suited to the substitution trunk. Look for music that fits the atmosphere and the tempo of the magic.
Secondly, perform your magic in time with the music. The important part of the magic, like the production of a card fan, should be at the same time as the important part of the music. The important parts of music include the "downbeat". This is the point on the music when you feel like tapping your foot. This beat in music is represented an the beat or count. A waltz for example has 3 beats or three counts to a measure. The musician counts 1-2-3, 1-2-3, 1-2-3. Likewise, the magician must feel the beat. This is 3/4 time. 4/4 time would be counted 1-2-3-4, 1-2-3-4, 1-2-3-4. It must be mentioned here that the most important beat is the first beat or count 1. The accent is on the first beat.
The third point is the volume. The louder parts of the music built up intensity and are more exciting. The ends of songs may have a loud, longer "TA DA". This announces the end.
So it is with magic. an exciting part of the trick should be timed with the exciting parts of the music or important parts such as the down beats. The production of something should be timed likewise. The end of the trick should be at the end of the music.
This is obviously not going to happen the first time you put a routine together. You will need to practice, perhaps change songs or even edit music to make things fit together. Lots of trial and error.