Danceable tempos

Each dance form has its "sweet spot" perfect tempo for those steps.  Music which is too fast often makes dancing difficult (if not impossible), while too-slow tempos can feel lethargic or boring.  At the bottom of this page is my list of tempo sweet spots for each kind of social dance.  The general rule of thumb is to keep the tempo within 10% (above or below) of the sweet spot, no more.

Next, here's one of the main secrets of being a great DJ:
A) Your tunes come in a range of tempos,               B) Some of your tunes have a driving high
above and below the sweet-spot tempo for             energy, and some have an easygoing low energy.
each dance form.

A and B must correspond.  Tunes with tempos above the sweet spot must have correspondingly higher energy, to support the extra effort required to dance faster, and vice versa for tunes below the sweet spot tempo.  This is a straightforward calculation.  (1) Get a metronome (click for an online metronone) or beat-checking software and find the tempo.  (2) Look at the sweet spot chart at the bottom of this page.  If the tempo is significantly above the sweet spot tempo, but it's one of the quieter, gentler tunes you have for that dance form, then don't play it.
Take a rotating (Viennese or rotary) waltz for example.  The sweet spot for intermediate dancers is around 144 bpm.  A common DJ mistake is to play a quiet ballad or gentle waltz that happens to be a fast tempo, say 160 or 170 bpm.  A good example is "You've Got to Hide Your Love Away" by the Beatles, or Pearl Jam's cover of it.  To the dancers (especially the leads) waltzing now feels like hard work — more effort is required at that fast tempo than the gentle music is providing.  But a powerful driving rhythmic tune at the same 170 tempo would be fine.

Conversely, playing a highly rhythmic driving waltz tune that happens to be a slower tempo, like 130 bpm, will fell terribly slow, while a gentle lyrical waltz at that same 130 tempo will feel perfect.

This is true for most dance forms — swing, salsa and others.  Match the higher or lower energy with correspondingly faster or slower tempos.


What do you do if you really love a tune and it's not at a good tempo for that dance?  Consider slowing it down or speeding it up, without changing the pitch.  There are many ways to speed up music without changing pitch, both with software and firmware.  Speeding up music is easy.  However slowing down music beyond 8% is technically much harder, without it sounding warbly or watery.  I recommend using Amazing Slow Downer software, available for both PC and Mac.  Music slowed down 20% or even 50% still sounds natural.

However this approach of slowing down or speeding up recordings is debatable.  I heard of a conservative dance group where some dancers protested if a tune was slower or faster than the original version they knew.  They complained with, "How can I like something that I'm not accustomed to?"  So if you live in a conservative area, this is your call.


The danger of the DJ being an experienced dancer:
You may be so adept at dancing that you forget that it's often difficult for a beginner to dance at a fast tempo that you find comfortable.  Some of the worst dance DJs I've seen are often the most adept dancers, because they don't know what's hard for the average dancer.  If you have many new dancers at your party, keep their comfort level in mind.