AudioBanter.com - View Single Post

(Scott Dorsey) wrote:

Brian nospam@hotmail wrote:
I have a BOSE Acoustimass 7 (3 saterlite speakers and bass speaker) I
brought this for surround sound. I have two BOSE VS100 small sized
speakers at the back of the room, near the ceiling.

I'm sorry.

I read in a article that the frequency range is:
Base module 46Hz to 202Hz at +-2.3dB
Satellites 280Hz to 13.3k Hz at +-10.5 dB
Can someone who has tested these speaker confirm that this is the
frequency range.

Sure. Those are useless numbers... you'll notice that the satellite
and subwoofer are listed with "ranges" that don't even overlap. If
you actually saw a sweep test on this crap, your eyes would bug out.
But those seem reasonable enough numbers for anechoic testing.

Notice the +-10.5 dB tolerances on the satellite test. Isn't that
hilarious? That basically makes the range itself pretty much
meaingless. If you use wide enough tolerances, you can say ANYTHING
has a wide frequency response.

There seems to be gaps at
20Hz to 46 Hz
202Hz to 280Hz and
13.3k Hz to 20K Hz.

There are gaps all over the place. Again, with such wide tolerances
you can't even tell how many there are. The frequency response on these
things basically looks like the Appalachians with really no midrange
to speak of.

I recently brought a sub woofer to try and full in the gap at the low
frequency range. The sub woofer is 28Hz to 200Hz.

And what's the response across that range?

The basic problem with all of these things is that the satellites are
too small to have any real midrange response. Below 1 KC or so they
pretty much fall like a rock and then the subwoofer picks up well below
that. You'll notice there is no bass imaging whatsoever, and that bass
runs basically sound like one note being played over and over. That
is because the bass itself is restricted to a fairly narrow range if
you actually look at the response plot.

Again, ignore the "ranges" because they don't tell anywhere near all
of the story, especially with those wide tolerances.

I can't see anyway of disableing the BOSE bass speaker so that the Sub
Woofer is used.

If you used a real sub with the Acoustimass satellites, you'd have no
midrange at all and things would be even worse.

I have a Surround 5.1 sound decoder in my DVD player and connected the
player to the ampilifer using 6 leads (one for each speaker). In doing
this I was hoping that the subwoofer would get only the low frewuency
sounds. I have since found that the cut off frequency for the sub
woofer filter built into the DVD player is 120K Hz. This leaves a gap
from 120K Hz to 202K Hz.
Another reason for connecting the amplifer with 6 leads was to be able
to play super audio cd's (SA-CD).

Basically, these systems are totally worthless junk and they are designed
to look good and sound exciting in the store, not to actually be accurate
to to listen to for the long term. There is no way to make the Acoustimass
system sound anything even remotely close to accurate.

Replacing these with a cheap pair of mid-fi bookshelf speakers will be much
more of an improvement than going to SACD sources ever will.
--scott

Thanks for your comments Kludge
If you want to take a look at the graphs for the test results they can
be found at www.intellexual.net/bose.html

Regards Brian