Despite of the rather “misleading”
efficiency graphs in their adverts during the 1990s, does the MIT loudspeaker
cables actually a “misadvertized” products that actually does its intended purpose
– i.e. improve sound quality?
By: Ringo Bones
A few months ago, I was fortunate
enough to rummage upon a used 1990s era MIT Terminator Network loudspeaker
cable in a garage sale. Priced at around 20 US dollars a set, it was almost a
steal. Even more fortunate, the former owner who is a radiologist used the box
of the cable when testing a newly purchased CAT scan for a hospital and noted
the values of the capacitors and inductors in the box from the X-Ray results –
i.e. the component labels of the capacitors are clearly visible and the inductor’s
values are determined by its dimensions and number of turns. I wonder why these
products managed to improve the dynamics of solid-state amps by making them
perform dynamic swings that has only been previously the domain reserved to
classic McIntosh vacuum tube power amplifiers. With the LC filter component
values sets its working frequency at around 45 Megahertz, I started to wonder
if the working principle of how the MIT loudspeakers improve sound quality is
similar to James Henriot’s Whest Dap 10
Processor – i.e. the elimination of the so-called “analog domain jitter”?
When Stereophile reviewer Jonathan
Scull quoted Matthew Bond of TARA’s white paper on the difference between
Musical Interface Technology’s products versus TARA’s from an August 1998
review of TARA Labs The One interconnect, loudspeaker cable and digital
datalink. Most readers are familiar with cables that use network boxes in-line
with the signal – i.e. MIT (Musical Interface Technology) Fadel Audio Art and
Transparent Cable come to mind. According to Matthew Bond’s own view regarding
these issues:
“These boxes contain low-pass
filter networks that filter radio frequencies (RF) from the audio cables. These
should not be confused with TARA’s Isolated Shield Matrix. The differences in
both function and effectiveness are extreme.”
“A filter network removes RF from
the audio signal by filtering out or rolling off all high-frequency energy
above a certain range. This generally affects the upper end of the musical
spectrum. Furthermore, these filter networks are directly in the signal path.
When the signal is interrupted and fed through these low-pass filter networks,
the cable’s electrical characteristics are changed to make a modified cable
interface with limited and unnatural filter characteristics. The high-frequency
bandwidth is reduced. The audio band is affected also, as it is subjected by
the filter network to rippling, and slower rise time (in the case of the
fourth-order Bessel low-pass filter). Furthermore, in a filter network RF
modulation has not been addressed properly because of the heterodyning effect
still occurs in the audio band. Additionally, the amplitude of the extremely
high-frequency harmonics of the music are filtered off, along with the RF
distortion, by generic capacitors and inductors in the network. The effects of
a filter network are therefore subtractive and ultimately color the original
signal. The Isolated Shield Matrix does not filter RF it grounds it outside of
the signal path. It transfers RF and EMI energy from the cable without
filtering the signal, thereby allowing ore high-frequency information to be
passed through unaltered.”
The problem is unofficially known
as “analog domain jitter” and even though Whest Audio founder James Henriot
doesn’t understand the disease but thinks he’s found a cure while promoting his
Whest Dap. 10 Processor featured in the July 2005 issue of Stereophile. Could
Musical Interface Technologies MIT network cables manage to improve the sound
by the same principle of eliminating “analog domain jitter”?
The Whest dap.10 works entirely
in the analog domain above 30,000 Hz, far above the range of human hearing. It is
also well above the 20,000 Hz limit at which your DAC’s filters curtail CD
sound. According to James Henriot, frequencies you can’t hear affect the ones
that you can hear. Other audio designers since the 1990s have stated the same
thing and so have musicians talking about their instruments. Musical Fidelity
founder Antony Michaelson who is also an accomplished musician who plays the
piano and clarinet in a classical setting also stated that things occurring above
the audible range have an effect on the sounds that you can hear.
According to James Henriot:“All
amplifier circuits produce a set of harmonics related to the incoming signal.
The output of a CD player is no different. Often referred to as “ghost images”
in a Fast-Fourier Transform display result, the time shift causes minor ripples
above 30,000 Hz. We think that these ripples have a profound negative impact on
CD reproduction, possibly by beat interaction, which dribbles its way down into
the audible frequency range. All electronic circuits – especially sold state
ones – may have a way of knocking harmonics out of sync, resulting in a less
musical and more electronic sound. Does this mean that building a musical sounding
solid-state amplifier is akin to building a concert grand piano with all those
string compensators?
