archive: Re: SETI Music to ETIs?

Re: SETI Music to ETIs?

David Woolley ( david@djwhome.demon.co.uk )
Sun, 20 Dec 1998 12:51:51 +0000 (GMT)

>
> IMHO, terrestrial music would be interpreted as noise by ETI. There is no
> way convey what music is. Understanding requires context. As mentioned

Human music is not noise like. It is composed of rythmic units and
frequencies which bear ratios to each other which are close to the ratios
of small integers. It also typically involves repetition with small
variations. It might get confused with signal, but it shouldn't get
confused with noise.

(The 12 note scale was originally derived by applying a series of simple
integral relationships. The result is a scale in which a lot of combinations
will not produce low beat frequencies. With twelve notes, you almost get
equal ratios, although they are not quite equal and instruments with a
natural key may only be able to play in that key well. Instruments like
pianos and organs are normally tuned to a compromise scale, where the twelve
notes are at root 12 (2) ratios, which is close enough for most purposes and
makes the result key independent, and would show up as clearly of
intelligent origin.

In fact, the pentatonic scale, which has quite low integers in the ratios,
seems to be more or less universal in traditional, popular, music. I'd
guess that music in such a scale might well be recognizable as music by
any species with music, as it would show a pattern of simple ratios, with
a controlled degree of randomness.)

PS please don't quote the whole thread to date in every reply.