Article View: comp.sys.mac
Article #15084Re: Mac II D/A resolution
From: grr
Date: Tue, 07 Apr 1987 06:10
Date: Tue, 07 Apr 1987 06:10
35 lines
2212 bytes
2212 bytes
In article <585@plx.UUCP> ed@plx.UUCP (Ed Chaban) writes:
>I've heard conflicting reports about the MacII's D/A resolution.
>Would anyone at Apple care to set me straight?
>
>How can you say the Mac II delivers CD audio quality with only
>8-bits of resolution? Exponential D/A converters A'la Amiga?
>I hope not...
>
>-ed-
Ed, old buddy, the Amiga D/A's are 8-bit *linear* with a 6-bit volume
control. You can view this as floating point if you wish, but it's
quite different from the exponential converters used on some "noise
generator" class chips.
The Mac II can manage a 44KHz sample rate, but it can't handle the
14-16 bits normally considered as CD quality.
The Amiga is nominally limited 8 bits, with a 28.8 KHz, but by playing
games with the multiple channels and volume controls you can get another
bit or two and get some rather impressive dynamic range. If you are
willing to dedicate the processor to sound generation you can directly
drive the sound channels to achieve >> 44KHz sampling rates. (a little
snip-snip on the low-pass filter helps here).
Still, 16-bit resolution at 44KHz would be nice, but one has to comtemplate
the noise floor in the personal computer environment, especially when using
on-chip converters.
I haven't seen/heard the Mac-II yet, but I have seen Bob Hoover demonstrating
his Mimetics/Soundscape stuff. Pretty nice...
--
George Robbins - now working for, uucp: {ihnp4|seismo|rutgers}!cbmvax!grr
but no way officially representing arpa: cbmvax!grr@seismo.css.GOV
Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!utgpu!water!watnot!watmath!clyde!rutgers!cbmvax!grr From: grr@cbmvax.UUCP Newsgroups: comp.sys.mac,comp.sys.amiga,rec.audio,rec.music.synth Subject: Re: Mac II D/A resolution Message-ID: <1640@cbmvax.cbmvax.cbm.UUCP> Date: Tue, 7-Apr-87 01:10:13 EST Article-I.D.: cbmvax.1640 Posted: Tue Apr 7 01:10:13 1987 Date-Received: Fri, 10-Apr-87 00:31:58 EST References: <585@plx.UUCP> Reply-To: grr@cbmvax.UUCP (George Robbins) Organization: Commodore Technology, West Chester, PA Lines: 35 Keywords: 16-bit?