This article is from the Recreational Figure Skating FAQ, by Karen Bryden with numerous contributions by others.
(Based on contributions by William Letendre and Lyle Walsh)
Whether you are cutting your own music for a competition or test
program or just want to have some of your favourite music to play
while skating, you may be surprised and disappointed by the difference
in sound quality when you hear the music on the rink system.
The main problem with sound quality is caused by reverberation
(multiple echo). In a typical Olympic sized rink, it takes sound about
0.2 seconds to travel the length of the rink. If the rink has plenty
of sound damping insulation on the walls, the sound can be reflected a
couple of times before it gets absorbed into inaudibility. In rinks
with bare concrete or steel walls, the sound can be reflected around
10 times. This results in a reverberation time between 0.4 and 4
seconds. It is easy to see why a long reverberation time leads to
problems in reproducing music. Most music at any tempo fast enough to
skate to has beats and sub-beats at much closer spacing than a second
or two; "allegro" tempo is generally played at a rate of anywhere
between 4 and 10 beats per second! Music at that fast a beat will
become "mush" when played in a "live" rink, with the notes so blurred
together as to be indistinguishable.
As it happens, the typical materials used in building construction
absorb treble notes much more effectively than they do bass notes.
This means that the effective reverberation time for, say, a flute
piece will be much shorter than that for a bassoon piece. This is a
lot of the reason that you want to avoid "bass heavy" music when
playing in a large, echoic space such as an ice rink. The higher
pitched notes will damp more quickly and sound more distinct.
Finally, if you are lucky enough to skate in a rink with good
acoustics, then you get hit from the other direction; short reverb
times imply high acoustic loss, which means you need more acoustic
power to produce loud sound. In fact, the high levels of power
required can easily defeat the output power capacity of battery
powered "boom boxes", forcing you to turn the volume up to the onset
of audible distortion and beyond!
While you cannot do much about the ice rink acoustics, it is possible
to edit your music to work around the limitations of the rink music
system. This can be done easily with music editing software like Sound
Forge, Goldwave or Audacity. Here are some tips:
1) Turn off the Bass Boost on the playback system, most are terrible
and will muddy up even the best recordings.
2) Use some form of dynamic compression, eg wave hammer, so that the
softest parts are no less than -15 to -20 dB and normalize all music
to peak value of 0 dB.
3) Add "air" i.e. boost the top frequencies above 15 kHz by 3 dB.
4) If there is a lot of difference between the right and left channels
then mix it in MONO as stereo is often lost and you can completely
lose the vocal or melody line.
6) Avoid cheap "pop" recordings, as their engineering is absolutely
7) If you record on tape for your program keep a virgin competition
tape and watch your recording levels so that you don't go over +3dB.