one uses tpdf dithering and the other uses sbm dithering process
well then it should most definitely sound better than the w-mod 
bit-mapping sucks IMHO (ducks)
Doug Oade disagrees
http://www.oade.com/cgi-bin/miva?showmsg.mv+message=1493Subject: Re: Quality Stealth Rig
Date: Sat, 17 Feb 2001 11:12:12 -0800 (PST)
From: Doug Oade <doug@oade.com>
Hey Now ! I want to take exception to the comment about the SBM-1.
Super Bit Mapped masters are widely acknowledged to be among the
best sounding releases available. This pioneering work by Sony was
"copied" by Apogee to develop their UV-22 ( very good indeed !) and
by Pacific Microsonics for the HDCD format ( again, excellent sound !).
All three of these technologies are used by golden ears to improve
the quality of their 16 bit recordings. The idea being to increase
the sense of resolution in 16 bit recordings. Many industry leaders
have come forward to praise the Super Bit Mapping algorithm as one
of the best, if not the best ( depends on who you ask !). This
technology, like 16 bit digital technology, is still in use today.
There is nothing outdated about these algorithms for 16 bit
applications, they are the state of the art for 16 bit PCM recordings .
These "encoded" recordings ( HDCD, UV-22 and SBM )sound better because
they are "encoded" with > 16 bits of actual musical information, as
compared to 16 bits for standard 16 bit recordings. Encoding data
overcomes the initial limitations of the 16-bit format by using a
sophisticated system to encode the additional bits into the data
stream while remaining completely compatible with the existing CD/DAT
format. Digital "overbit" encoding provides more dynamic range, a
more focused 3-D soundstage, and extremely natural vocal and musical
realism, you get the body, depth and most important, the emotion of
the original performance at original performance playback levels.
Yes, I can hear the coloration added to a recording by the SBM
process ( and EVERY OTHER piece of audio gear out there !), but I
can hear the improvements as well. The SBM-1 is a fine A/D converter
( hardly the best, but a very good one), although it does have noise
shaping, something a lot of folks do not like. The SBM-1's noise shaping
concentrates in the 3-4 Khz region, which is less offensive than
noise shaping that works above 10Khz, typically 15 Khz to 22Khz. This
second type of noise shaping, designed for classical and unamplified
music, causes severe problems when used to record music that is
played back at rock concert levels. The high end noise is so audible
at rock concert levels as to create an odd form of distortion, that
seems to trash transients to the point they "spit" or "crack". These
noise shaping systems were developed by design teams that listen to
music at less than rock concert levels, so you can understand why the
HF boost( < 22Khz )noise shaping techniques sound bad when processed
or played at rock concert levels ( some provide TPDF for loud music ).
Apogee UV-22 adds noise above 22Khz, much like the bias signal on analog
tape recorders, this does not adversely affect the signal.
If you want to digitally process this type of recording after the
fact on a computer, for example, and try to EQ the high end up, the
problem gets worse ( unless you record classical, bluegrass, jazz or
other unamplified music, which I do and love). This is because you are
increasing the level of 15 Khz noise added to the signal to mask the
effects of word length reduction and quantization errors. I do not know
about you, but my rock recordings sound best when played LOUD ! There is
simply too much dynamic range to listen to them at low SPL. I want
peaks of 105 to 115 at my listening postion, depending on the
recording. I want the power of the emotional experience of live music
at realistic levels ( I do not say "what " all the time either, I
save my ears for the good stuff, otherwise I use earplugs !)
When you look at the SBM-1, you will note an A/D converter with a
6.144 MHz 24 bit capable DSP chip. It has so much power, it can
handle 4 24 bit data streams and can output 24 bit 96 Khz data rates ! A
few upgrades to the power supply, replace some older IC chips a few
chip capacitors and you have an amazing, SMALL state of the art
A/D converter. Give up the battery compartment and it can power
your mics. The list goes on, I like the SBM-1.
Peace...Doug
BTW, If you are interested, go to the manufacturers sites for detailed
explanations of these three different, but effective techniques to
enhance the resolution of 16 bit recordings.
Topic: what is the difference btwn the Oade t-mod and warm-mod SBM-1..? (Read 7288 times)