Dario:
Regarding my initial response (which doesn't seem to
have appeared yet on the listserv), it turned out to be
trivial to create a variable-length noise sequence listening
test, but much harder to actually *take* the test. The
upshot is that this is probably not what you want to do.
I used the Daqarta Generator to create continuous white
noise, and used the DDisk option to record 60 seconds of
that. Then I switched the Generator 'Wave' type from
simply generating white noise, to using the file as the
source in Play mode. Play mode lets you specify start
and end points and automatically loops, so you can get
any sequence length you want, and you can change the
specific sequence by picking a different section of the file.
One second is trivially easy to hear patterns in, but as you
go up in time it depends a lot on the particular section of
noise: If there are "features" that stand out, you can often
hear the sequence of features as something like
'dadaDAdaDA'. But since it depends so much on the
chunk of noise you choose, it isn't a good way to tell
anything about human limits on pattern recognition...
there might not be a pattern in the chunk you choose.
So I'm guessing that you are probably more interested in
something like a random series of musical notes.
Daqarta can easily do this using its MIDI options. (Let me
know if you are interested. It's also free.) But here the
testing would be pretty tedious, since humans seem to
have a pretty good ability to distinguish musical
sequences, again depending on the sequence. The more
'random' it sounds (less 'musical') the harder it is. After
all, music perception is all about pattern recognition!
Best regards,
Bob Masta
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