Psychoacoustics, Gamelan tuning

Below are the rest of the articles Jim Murray found for me.

Ralston, James V.; Herman, Louis M. "Perception and generalization of
frequency contours by a bottlenose dolphin (Tursiops truncatus)."
Journal of Comparative Psychology, 1995 Sep, v109 (n3):268-277.

Abstract: A single adult female bottlenose dolphin was tested in a
series of perceptual studies. On each trial, 4 sine-wave tones were
presented that contained a falling frequency contour or some other
contour. There were several frequency-transposed exemplars of each
contour type in each experiment. The dolphin discriminated contours
at a level significantly greater than chance in all experiments. In
the 1st 2 experiments, the dolphin demonstrated only modest transfer
to novel stimuli and a sensitivity to the absolute frequency of stimuli.
In the 3rd experiment, there was no effect of the absolute frequency of
stimuli; in the 4th experiment, the dolphin successfully transferred the
discrimination to novel stimuli drawn from the octave above the
previously heard range. These results demonstrate dolphins' capability
to perceive frequency contours, which may underlie the recognition of
conspecific whistles.

Cynx, Jeffrey. "Auditory frequency generalization and a failure to
find octave generalization in a songbird, the European starling
(Sturnus vulgaris)." Journal of Comparative Psychology, 1993 Jun,
v107 (n2):140-146.

Abstract: Examined frequency generalization in starlings (Sturnus
vulgaris) that were trained to discriminate between individual
frequencies. Starlings were tested for frequency generalization after
training on 2- and 3-tone discriminations. There was no evidence for
octave generalization, which is a hallmark of human absolute pitch
perception. This suggests that avian absolute pitch perception must not
be interpreted as identical with that in humans. A control experiment
with 1-tone discriminations indicated that the presence of lit response
keys affect the shape of the generalization gradients. Lit response keys
are a common feature in avian auditory perception experiments, and this
control experiment cautions that results may be affected by this
seemingly minor procedural change.

Hulse, Stewart H.; Humpal, John; Cynx, Jeffrey. "Discrimination and
generalization of rhythmic and arrhythmic sound patterns by European
starlings (Sturnus vulgaris)." Music Perception, 1984 Summer,
v1 (n4):442-464.

Abstract: Investigated the ability of mature wild-caught European
starlings (Sturnus vulgaris) to process acoustic patterns with
different, serially organized temporal structures. Four of the
Subjects were female; 2 were male. Subjects were taught to discriminate
patterns of 2000-Hz tones organized into rhythmic as compared with
random, arrhythmic temporal structures, and the perceptual processes
underlying the discrimination were analyzed. Subjects were required to
peck at one key in the presence of a rhythmic pattern and at another
in the presence of an arrhythmic pattern. Results show that all Subjects
learned to discriminate between rhythmic and arrhythmic patterns and
that discrimination accuracy was the same for linear and hierarchical
rhythmic structures. In a series of transfer tests that followed,
discrimination performance was tested when the temporal structure of
the rhythmic stimulus patterns was transformed and when the pitch was
shifted up or down 1 octave. Performance was well-maintained when
baseline temporal patterns were shifted 1 octave. Results suggest
that the Subjects solved the rhythmic-arrhythmic discrimination on
the basis of rhythmicity.


And now for something completely different, Gamelan tunings on
Roland synths, forwarded from the Gamelan List out of Dartmouth.

Date: Sat, 13 Jul 1996 10:07:30 WIB
From: Al Nurbandana
Subject: Laras Gamelan in Roland 86

For those who like both the diatonic scales and the gamelan pentatonic
scale.

I just made tune adjustment in one of the program of my Roland 86 to
make the organ usable to play gamelan instruments with the pentatonic
music scales.

The basis of 'laras' gamelan is tone 6 (nem) and 2 (ro) for slendro,
pelog bem and pelog barang. For scale 6, I use Bb with pitch adjusted
+47 steps higher - most gamelan has more or less laras 6 similar to that
tone. For scale 2, I use Eb with pitch adjusted +37 steps higher.

Slendro scales:
1 = C# | 2 = Eb +37 | 3 = F# -33 | 5 = Ab +15 | 6 = Bb +47

Pelog Bem Scales:
1 = D | 2 = Eb +37 | 3 = F | 5 = A | 6 = Bb +47 ----> 4 = Ab +15

Pelog Barang Scales:
1 = C | 2 = Eb +37 | 3 = F | 5 = A | 6 = Bb +47 ----> 4 = Ab +15

It is obvious that laras gamelan is not a simple break of tones by half
like in a piano (both slendro and pelog). Please explore and you will
see. If you have a Roland E86, 'Happy trying !'.

Nuwun,
Al Nurbandana
Phone:(0761)594621,593402 Internet: alnurba%mcscpi.ptcpi.com

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Topic No. 5

Date: Sat, 13 Jul 1996 04:11:44 -0400
From: Tom Ross
Subject: Re: Laras Gamelan in Roland 86

Al: so far so good. But aren't instruments such as peking tuned sharper
than, say, slentem? What to do about that? Some synths, such as the EPS
16+ and Kurzweil 2000, allow overall ['global'] tuning, which I think
you're describing, as well as tuning of individual sounds or
'instruments.'

I assume the steps are tuning units, 1024 to the octave?, or does
Roland use another system I'll post any reply to Tom Ross's question.

--John