Subject: MAX Digest - 26 Dec 1999 to 27 Dec 1999 (#1999-370)
Date: Tue, 28 Dec 1999 00:00:06 -0500
From:
Automatic digest processor <LISTSERV@LISTS.MCGILL.CA>
Reply-To: MAX - Interactive Music/Multimedia Standard Environments <MAX@LISTS.MCGILL.CA>
To: Recipients of MAX digests <MAX@LISTS.MCGILL.CA>


There are 3 messages totalling 127 lines in this issue.

Topics of the day:

  1. integers/floats/accuracies
  2. cycling 74 server down
  3. Infos CDxtract

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Date:Mon, 27 Dec 1999 09:43:10 +0000
From:Lawrence Ball <Lawrenceball@PLANETTREE.DEMON.CO.UK>
Subject: integers/floats/accuracies

> From: "Lawrence Ball" <Lawrenceball@planettree.demon.co.uk>
> Subject: integer/floats
>
>
> Hi jhno, and all maxers,
>
> Having done a lot of pieces in the mid 80s (with 8-bit sound!!!!), (and
> currently attempting to do extensions of that work with MSP) that utilised
> highly carefully structured patterns of DAC values, I am very interested in
> your remarks about numbers.
>
> I'm particularly interested and intrigued at the idea of floating-point
> being so tiered in its plateaux of densitites.
> If I'm not mistaken, Sound Manager and many sound cards will convert all
> that fine tuned accuracy into a bare lattice of 16-bit sound. Which I wonder
> is what exactly?
> Does this mean that the DAC voltages available are stepped in 32767 (or -8)
> intervals either side of a centre? Or is there some more complex mapping.
> Does the 32bit float get converted simply into the nearest 1/32767th ? Plus
> or minus - depending on the value? Do DACs deal in integer values these
> days?
>
> Any precision values of knowledge will be very gratefully calibrated,
>
> By the way that tutorial URL didn't work (on my browser anyhow),
> Siriusly,
>
> Seasonal greetings and extenuations
>
> Lawrence Ball
>
>
> Date:
Wed, 22 Dec 1999 01:25:08 -0800
> From:
jhno <ear@SIRIUS.COM>
> Subject: floating among the points

> ....msp uses the 32-bit IEEE 754 floating point representation provided by the
> power pc processor. the interesting thing about this format, from an audio
> perspective, is that precision varies depending on the magnitude of the
> number you are encoding. this is because a floating point number is
> specified by a "fraction", which is raised to an "exponent" to produce the
> number you are trying to describe......
>
> .......the practical upshot of this is that precision is greatest near zero, and
> diminishes as you count upward. for example, you can precisely specify over


> 8 million real numbers between 0.0000001 and 0.0000002 - but only two
> between 8,388,607 and 8,388,608. larger than that, the precision is so
> coarse that the difference between consecutive real numbers is greater than
> 1........

> .......the interesting thing is that the increase in precision as you approach
> zero does not occur smoothly... it occurs in steps, at each negative power
> of 2. so, floating point real numbers are equally spaced between 1 and 0.5,
> but then the precision changes and they are twice as dense between 0.5 and
> 0.25. floating point can specify exactly the same number of unique numbers
> between 0.5 and 0.25 as it can between 0.5 and 1.......
>
> anyway, i'd be interested to know if anyone has any thoughts on practical
> implications of these concepts.
>
> i learned a little about IEEE 754 from this little tutorial:
>
> http://www.public.iastate.edu/~selavi/ieee.html
>
>
>
> jhno
>
>
> () ))
(((( ))) ))))) ( )((()) (( ))( )) (((( )(()( (()
> delicate ear
ear@sirius.com
> san francisco, cahttp://www.sirius.com/~ear
>
> ------------------------------
>

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Date:Mon, 27 Dec 1999 13:34:23 +0000
From:Roger Carruthers <roger.carruthers@VIRGIN.NET>
Subject: cycling 74 server down

apparently I am forbidden to access anything on the cycling74 server; is it
just me or is this a seasonal server hiccup ?

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Date:Mon, 27 Dec 1999 12:13:58 +0100
From:Eric MAUER <emauer@WANADOO.FR>
Subject: Infos CDxtract

Chers Maxers
Nous avons le plaisir de vous annoncer la mise à disposition de
CDxtract, le nouvel utilitaire PC de lecture, conversion et gestion des
CDROM AKAI, ROLAND, SOUNDFONT. (programmes et sons .WAV et AIFF)
Renseignements et telechargement demo :
http://www.amazingsound.com
Disponible a la vente sur notre site a partir du 15 janvier.
Sincerement
Eric MAUER - Fred SAVOIR - Bernard CHAVONNET


Dear Maxers
We are pleased to announce you the new PC software, CDxtract, to browse,
convert and manage your CDROM AKAI, ROLAND, SOUNDFONT. (programs and
sounds .WAV and AIFF)
Informations and download demo now :
http://www.amazingsound.com
On sale as from January 15th on our website.
Best regards
Eric MAUER - Fred SAVOIR - Bernard CHAVONNET


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End of MAX Digest - 26 Dec 1999 to 27 Dec 1999 (#1999-370)
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