|
Here is a second tutorial that helps if you use vinyl, Ableton Live's "Repitch" mode, or CD-Js *without* master tempo:
How does changing the tempo change the key?
If you use DJ equipment without a "Master Tempo" function, changing the tempo of the song will change its key as well. Even the smallest tempo change will alter the key, but a 6% difference will change the key to a whole new one.
6% Rule
6% is the magic percentage: it will move your song to the adjacent key on the piano, as illustrated below:

If your original song was recorded in F Minor, increasing the tempo by 6% will move the song one key to the right to give you G-Flat Minor.
This is equivalent to adding 7 numbers to your current Camelot keycode. Since F Minor is also known as 4A, adding 7 will give you 11A. The piano roll above shows you that 11A is indeed equivalent to Gbm.
Decreasing the tempo by 6% has the reverse effect: It moves your song one key to the left, or the equivalent to subtracting 7 from your current Camelot keycode. This is illustrated below:

3% Rule
There is a basic rule for small increments: If you change the tempo by less than 3%, keep your original key. If you change the tempo by 3% or more, use the 6% key.
3% is the middle point. Anything below 3% will be closer to your original key (F Minor) and anything above 3% will be closer to your 6% key -- Gb minor or E minor, depending whether you increase or decrease the tempo.
Examples
- Two songs in F Minor that have roughly the same BPMs: 130 and 131. We can mix them together because the tempo difference is less than 3%.
- Two songs in A Minor with different tempos. First song is 128 BPM and the second is 136 BPM. To beatmatch the slower song with the faster song, we’ll have to increase its tempo by exactly 6.25%. This will move the slower song one key to the right, making it B-flat Minor rather than A Minor. The new keys will no longer result in a harmonic mix because A Minor (8A) and B-Flat Minor (3A) are not compatible Camelot keycodes.
Using “Master Tempo”
If your DJ equipment or software supports “Master Tempo,” use it! Master Tempo is a pitch-correction technique that makes it easy to use harmonic mixing at any tempo. If you increase the tempo of an A Minor song by 6.25%, your “Master Tempo” function will keep the song in A Minor.
Conclusion
In summary, if your tempo change is less than 3%, use the original key. If your tempo is greater than 3%, use the 6% key. The new +6% key can be figured out by adding 7 to your current Camelot keycode. The new -6% key can be figured out by subtracting 7 from your current Camelot code.
Cheers,
Yakov
|