Musical Tempo Change To Note Value Conversions!

Posted by on May 22, 2020 in Arranging, Composition, General Music | Comments Off on Musical Tempo Change To Note Value Conversions!

A handy calculation to help you convert consistent sounding notes while changing the tempo.

Have you ever written anything (DRUMMERS) that started with continuous eighth-notes, for example, and you wanted those eighths to become eighth-note-triplets by only changing the tempo? The most clear cut way to do this would be to change the tempo, and if you know this calculation you can figure it out fast!

Both rhythms in the measures above sound the same to the listener.

In the above example if you started out with eighth-notes at 180bpm and wanted to change them to eighth-note-triplets without it sounding any different you would have to write the eighth-note-triplets at 120bpm. Eighth-note triplets at 120 sound exactly the same as eighth-notes at 180.

Easier example: If you have eighth-notes and want to switch to quarter-notes you need to multiply the first tempo by 2. To go the other direction you need to divide by 2. If your note value would be slower if you stayed the same tempo you’ll need to multiply, if it would be faster at the original tempo you’ll need to divide.

Here’s a foolproof list of calculations for you to use with most standard note values, just find the conversion you’re looking for…

whole-note to half-note: multiply tempo by 0.5
whole-note to quarter-note: multiply by 0.25
whole-note to quarter-note-triplet: multiply by 0.1666
whole-note to eighth-note: multiply by 0.125
whole-note to eighth-note-triplet: multiply by 0.8333
whole-note to sixteenth-note: multiply by 0.0625

half-note to whole-note: multiply tempo by 2
half-note to quarter-note: multiply by 0.5
half-note to quarter-note-triplet: multiply by 0.333
half-note to eighth-note: multiply by 0.25
half-note to eighth-note-triplet: multiply by 0.1666
half-note to sixteenth-note: multiply by 0.125

quarter-note to whole-note: multiply tempo by 4
quarter-note to half-note: multiply by 2
quarter-note to quarter-note-triplet: multiply by 0.666
quarter-note to eighth-note: multiply by 0.5
quarter-note to eighth-note-triplet: multiply by 0.333
quarter-note to sixteenth-note: multiply by 0.25

eighth-note to whole-note: multiply tempo by 8
eighth-note to half-note: multiply by 4
eighth-note to quarter-note: multiply by 2
eighth-note to quarter-note-triplet: multiply by 1.333
eighth-note to eighth-note-triplet: multiply by 0.666
eighth-note to sixteenth-note: multiply by 0.5
eighth-note to sixteenth-note-triplet: multiply by 0.333

sixteenth-note to whole note: multiply tempo by 16
sixteenth-note to half-note: multiply by 8
sixteenth-note to quarter-note: multiply by 4
sixteenth-note to quarter-note-triplets: multiply by 2.666
sixteenth-note to eighth-note: multiply by 2
sixteenth-note to eighth-note-triplets: multiply by 1.333
sixteenth-note to sixteenth-note-triplets: multiply by 0.666
sixteenth-note to thirtysecond-note: multiply by 0.5

Now, if you want to get crazier with any extreme conversions I left off you can do this pretty easily by taking a number you know and cross multiplying it to find the answer you don’t know. But first you need to understand how the math works. Basically I’m breaking down how many note values fit in a standard 4/4 measure (common time), which is a very simple way to remember how to do this. If you have quarter-notes for example you’ll represent them with the number 4, because there’s 4 quarter-notes in a measure. So whole-notes are 1, half-notes are 2, eighth-notes are 8, sixteenth-notes are 16, etc. But what about the triplet variations? Well just see how many fit in a single measure: quarter-note triplets is 6, eighth-note triplets is 12, and sixteenth note triplets is 24. Technically instead of calling any of these triplets we could just use the term of the number like all the standard values. So if you wanted to call eighth-note-triplets “twelfth-notes” you could, but most people won’t understand what that means on the fly.

Now, back to the math. If you currently have quarter-notes and you want to convert to eighth-notes you can cross multiply by taking the first number and dividing it by the number of where you want to go. So your current note value is the numerator and your target note value is the denominator. This example would be 4/8 which equals 0.5, and you can go ahead and multiply the tempo by that answer! Done!