Songs of right length

You usually don't have to worry about your tunes being too short, but in the rare instance of having a favorite tune that's only one minute long, you can make a double or triple-length version easily, splicing together repeats of that tune, into one longer version, while maintaining the beat.  Music editing software is a good way to do this.

The far greater problem is a tune lasting too long, usually meaning more than three minutes.  It's a twofold problem.  (1) Most social dancers would prefer to have four 3-minute dances with four partners than two 6-minute dances.  Variety and contrast are good.  (2) Many leads/men feel that their repertoire of freestyle dance figures is exhausted after two or three minutes, and they would much rather move on to something else.

Since many recordings are longer than three minutes, you have two choices: fade the song out at about three minutes, or edit out a central part to retain the original ending.  I always listen to the original ending to see if it fades out, as much popular music does.  If so, then I'll know that an earlier fade-out at 3 minutes is okay.  But if there's a definitive ending (which is especially important in swing and tango) then I'll edit out some central strains to bring the song down to three minutes.  If the song is four minutes long, I'll listen through the piece several times, searching for the minute which I can remove from the center without harm to the song, usually a verse and chorus among many repeats of that verse-chorus.  If the lyrics are telling a story, you might worry about removing an important middle part of the story.  Don't worry — dancers are too occupied with dancing to be listening to the lyrics.  Once again, there are plenty of software options for editing middle sections out of music to make a 3-minute dance version.

Exception 1:  Some fast and exhausting dances might want to be shorter than three minutes, like a fast techno polka for instance.

Exception 2:  Some dance traditions favor long songs, like salsa.  And some groups are so specialized, like West Coast Swing clubs, that the leads know hundreds of variations for that one dance form, and are happy with longer songs.  Good DJs ask what the dancers prefer, including song lengths.  Dancers' wishes always come first.

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.

Dancers want to hear the beat

Most dance forms are easier to dance when the beat is heard clearly, usually played by the rhythm instruments (drums/percussion, guitar, piano, techno rhythm tracks, etc.).

On a rhythmic intensity scale of 0 to 10, most dance music wants to be in the 4 to 10 range, depending on the type of dance.  Concert music for listening can have a quiet rhythm accompaniment or none at all, but the rhythm of most dance music should range from a gentle but clearly audible rhythm (4) to a strong driving rhythm (10).  Even quieter dance forms like rumba and club two step should have a clearly audible beat.  With only a few exceptions, avoid the quietest scale of 0 (no rhythm instruments at all, only melody) to 3 (still not clear enough to hear in a room full of dancers who might be shuffling and talking).

Shuffling and talking?  Yes, dance parties are usually noisy.  One of the common mistakes DJs make is to listen to a tune in a quiet room and think that the quiet rhythm accompaniment will be heard at a dance.  Then they find that the rhythm is lost in ambient noise of a dance party.  So if you're test-listening to music in a quiet room, aim for one or two notches stronger rhythm than you think will be needed.

When I hear dancers complain about a DJ, the most common complaint is, "I couldn't hear the beat."  The second most common complaint is about tempos...