Going to MARS
Edward Devlin
thinks I went there quite a while ago when I started this hobby. MARS
stands for McShane Ambience Recovery System. The MARS system utilizes
a simple passive crossover and dual voice coil woofers. One set of the
voice coils gets normal program information, the other gets ambient
information from the MARS crossover network. I was suspect of this
system, because I normally use a surround sound processor and matched
speakers to get my ambient information. But my concerns appear to be
unfounded. The system works very well indeed. I currently am using two
MARS based systems, one is a Fried Valhalla system which uses a full
passive crossover, the other is Fried's larger O4/C6
subwoofer/satellite combination in a biamped mode utilizing an
electronic crossover.
The Vahalla system is in a large room (18 x23x10) that communicates
with another similar sized room through a large opening. The speakers
are set up well away from the walls. The MARS system markedly
increases the depth and width (more about this later) of the
soundstage and gives a nice sense of hall ambience. Like any well
setup surround system, the image collapses when the MARS circuit is
removed from the signal path. There is also a lot of variability in
the amount of ambience depending on how the recording was made. That
is the system is pretty software dependant like any ambience recovery
system.
The other biamped MARS based speakers are downstairs in a 8.5x18x23
foot room. Here the MARS system has been giving me lots of
problems. This is a nice room, but it really sucks up the bass. As a
result, when I biamp I boost the subs about 8db relative to the
subs. At first, I thought MARS would not work in a biamped
situiation. But I have been spending a lot of time with Chuck on the
phone and it looks like it is going to work.
My problem was when using an electronic crossover with the MARS system
there was too much ambient information. It gave a very unusual
effect. The left and right channel information appeared to be comming
not from the front speakers, but almost immediately lateral of my
listening position. Chuck finally said that inserting some resistors
in the interconnect between the two speakers (ambient voice coils are
interconnected in this scheme) you can attenuate the ambient
information. This is going to be great. I plan in inserting a stepped
attenuator in this interconnect. By doing this, I will be able to dial
in the amount of ambient information I want. If anything, for my
tastes, there is a little too much ambient information in the MARS
systemthe way it is comming from Fried and I have told this to
Chuck. Putting a volume pot or a series of switchable resistors in the
path allong the speaker interconnect will allow listeners to select
the amount of ambience recovery they want in the system.
Right now Fried Products are the only company that is doing MARS
because of a one year exclusive Fried has with the system. This year
is just about up and look for MARS in a number of other speaker
manufactures shortly. I have only been playing with the system
operating properly for a few days now, but it looks very promising. It
eliminates many of the problems of using a surround sound system,
especially the matching of the rear channel speakers, cables and amps
all of which make it difficult to properly set up a surround system.
Ed Devlin
Mike Fenech
(Edward Devlin) wrote:
> Right now Fried Products are the only company that is doing MARS
> because of a one year exclusive Fried has with the system. This year
> is just about up and look for MARS in a number of other speaker
> manufactures shortly.
Good post...one correction:
Van L Speakerworks of Chicago has had a 'MARS' enhanced speaker
available direct mail for a little over a year now. It runs $900/pr.
They offer a 30-day trial period. I tried them out last fall and
thought they were great, although at the last minute I decided to wait
for the Fried's to come out...at the time Fried was promising their
entire line would be MARS equipped by this time, and they still have
not updated the projected release date for the lower half of their
line. I recommend anyone interested in this technology to try out the
Van L version. (Their ad runs in Stereophile.)
Mike Fenech
mike_...@netsolve.net