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Re: perception of rise/fall times

Dear Dr.Phillips,

I published a paper titled "Detectability of switching transients" (Journal
of Acoustical Society of Japan, in Japanese,1980). Let me send you the summary
of the paper translated to English which appeares at NHK Laboratories Note(No.275).
I am afraid whether my paper will be a reference for you or not, because it is
too old.

The abstract is as follows;
The detectability of clicks perceived at onset and offset of a brief sinusoidal
signal is measured as a function of the Sensation Level (SL) of the tone raging
>from 30 to 70dB SL.
The tone frequencies are 400 and 2000 Hz, while the two types of amplitude
envelopes (linear and expotential) are employed.
The results show that the critical rise or decay time (tc1, tc2) required to
achieve clickless signals depend on the level, the onset or offset slope and
the signal frequency, while does not depend on the initial phase of the tone.
As the SL of the tone is decreased, it is necessary to decrease the onset or
offset slope in order to achieve clickless signals.
The critical decay time is about 1/3 times as small as the critical rise time.
This means that the transient clicks are less audible at offset than at the onset
of the tone.
It is shown that the average data can be well fitted with the equation
(I/J) $B!& (Btcj** $B&A (Bj=constant, where  $B#I (B and J are the tone intensity and the threshold
intensity, respectively, and  $B&A (Bj  is constant depending on the signal frequency,
while tcj is the critical rise (j =1) or the decay  (j =2) time.
A running average model is shown to be effective to account for the above results.

> Hi Everyone:
> Are there published data on the similarities and/or differences between the
> percepts aroused by rise times and fall times (of tonal or other signals)?
> I'm not so much interested in increment and decrement thresholds per se, as
> I am in discrimination of the shape (e.g., linear, cosine) and slopes of
> the stimulus envelope.  We have the article by van Heuven & van den Broecke
> (JASA, 1979, 66: 1308-1315).  We also have the paper by Cutting & Rosner
> (P&P, 1974, 16: 564-570).  We're currently searching the literature for
> people who've cited those articles.  I would have thought that forward
> masking effects would have introduced asymmetries in the perception of rise
> and fall envelopes.  Is this not true?
> Parenthetically, we are aware of much of the literature on the neural
> coding of stimulus transients.
> Thanks very much for any help or guidance you can offer.  Best wishes from
> beautiful and sunny Nova Scotia.  Cheers,
> Dennis Phillips

(Mr.)Eiichi Miyasaka
 NHK Science & Technical Research Labs.
 Tel:+81-3-5494-2201 Fax:+81-3-5494-2459
 1-10-11 Kinuta,Setagaya, Tokyo 157-8510