Word Length Reduction Algorithm
innovative new technique for digital audio
Word Length Reduction (WLR) is now available
from the Pow-r Consortium, LLC. Some of the
world's top digital audio designers have
come together as a team to create what is
being hailed as the audio industry's most
transparent and dynamically stable method of
reducing digital audio word lengths.
Pow-r, an acronym for Psychoacoustically Optimized Word length Reduction, is a
unique, patent-applied-for algorithm, which reduces longer word lengths (20, 24,
even up to 32 bits), to CD standard 16-bit format while retaining a high degree
of perceived dynamic efficiency and very low noise. Pow-r is a scalable
algorithm, meaning it is dynamically optimized and ready for all sample rates
from 44.1kHz to 192 kHz, and beyond.
Pow-r is compact and designed for portability. The algorithm will operate
optimally in both DSP and native software in digital audio workstation
applications. Pow-r is technically not noise shaping. Rather, the original Pow-r
algorithm is based on narrow-band Nyquist dither and is free from artifacts
present in other popular Nyquist-band WLR techniques, such as "birdies" and
"motor boating." With Pow-r, archaic look up tables are avoided and all audio
program is decorrelated from Nyquist-band dither. To better target all audio
sources, non-narrow-band techniques are also offered in the POW-r algorithm set
Pow-r has been licensed by a number of key pro audio companies, including Apple:
Logic Pro, Avid/Digidesign: Pro Tools, Cakewalk: Sonar, Magix:
Samplitude/Sequoia, Merging: Pyramix, SADiE, E-Magic, BIAS Inc., Clair Brothers
and many others. Moreover, the four Consortium development members (below) are
all licensees of POW-r.
The Consortium development team is comprised of:
- David McGrath, Founder & Chief
Scientist, Lake DSP Pty, Ltd., Australia
- Daniel Weiss, President, Weiss
Engineering Ltd., Switzerland
- John La Grou, President, Millennia
Media, Inc., USA
- Dr. Glenn Zelniker, President, Z-Systems, Inc., USA
The Pow-r design consortium was assembled for the sole purpose of creating the
most sonically transparent digital word length reduction algorithms available.
After months of development and extensive listening tests, we feel our goal has
been achieved. A number of audio industry leaders, including major record
companies and numerous audio mastering houses, have called Pow-r the finest
sounding WLR method available.
"The POW-r noise shaping is the quietest and the best I've heard so far, no
question. It gives the music a slightly "pillowy" effect, smoothing out the high
end in a very pleasing way...very, very nice."
Dr. Toby Mountain, Northeastern Digital, February, 2000
I've also just finished reviewing POW-r. In my opinion, all other WLR schemes
are mostly obsolete. The POW-r Consortium has provided the music industry with
tools and methods to preserve the quality of high resolution audio in 16 bit
renditions. The POW-r process is the closest thing to perfection that I have
heard to date.
Glenn Meadows, Chief Engineer, Masterfonics Emerald Mastering, Nashville,
Over the years at Telarc, we've gone through the whole range of dithering
schemes to keep PCM well-behaved -- everything from levels of DC to white noise
and various noise shaping curves. We had eventually come to employ the xxxx
dither as our standard means of getting from 20- and 24-bit PCM to the 16-bit
PCM CD master.
Our introduction to POW-r word length reduction changed all of that. POW-r is
making it possible to have so much more of our 24-bit master represented on the
16-bit CD than we could do with other dithering or word length reduction
algorithms. I have been able to have a signal level near -120 dB from digital
peak in 16-bit still be audible and not distorted. That great increase in depth
better represents the width and depth of the 24-bit PCM master in its 16-bit CD
form than the other means of dither available, in my opinion. In fact, Telarc's
producers insist that POW-r word length reduction be used exclusively of all our
PCM-source masters. Once one hears something this good, there's no going back!
Michael Bishop, Multi Grammy Award Winning Engineer, Director of New
Technology, Telarc International, Cleveland
"For about 8 years, I've been doing shootouts of re-dithering algorithms, and
every system I tried was unable to recover ambience as well as my venerable ****
unit. But when I heard [POW-r], I began to cry, because I couldn't believe my
ears---this box brings 16-bit audio closer to the 24-bit source than I had
dreamed possible. This includes previous tests of [virtually all top dithering
algorithms], and other lesser-known varieties of dither.
Until I heard [POW-r], I thought that every dither was a compromise; some
sacrificed ultimate depth and space for a pleasant tonality, or vice-versa. The
POW-r dither seems to have broken a new barrier, removing the compromise of
tonality versus depth."
Bob Katz, President, Digital Domain Mastering, Pro Audio Review Magazine,
Full Text here.
The Pow-r Consortium, LLC is a "non-competitive," autonomous entity established
for the sole purpose of licensing, supporting, and marketing the Pow-r software.
For licensing information, please email: