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Path: utzoo!watmath!watnot!watdcsu!herbie
From: herbie@watdcsu.UUCP (Herb Chong [DCS])
Newsgroups: net.audio
Subject: Re: howzitdone?
Message-ID: <1403@watdcsu.UUCP>
Date: Thu, 23-May-85 10:36:17 EDT
Article-I.D.: watdcsu.1403
Posted: Thu May 23 10:36:17 1985
Date-Received: Fri, 24-May-85 02:47:45 EDT
References: <30200012@siemens.UUCP>
Reply-To: herbie@watdcsu.UUCP (Herb Chong [DCS])
Organization: U of Waterloo
Lines: 49
Summary: 

In article <30200012@siemens.UUCP> bhs@siemens.UUCP writes:
>What was amazing about these speakers was the top - quality sound ( no flames,
>please, if I say that the sound is good, it is as far as I am concerned )
>emanating from such small speakers. The speakers did not seem to be much taller
>than 1.5 feet, by 1 by 1 foot. They were mounted on relatively tall pedestals (
>ca. 2.5 feet ). Furthermore, they were also somehow connected or at least
>associated to a small black box called Bass Distortion Reducer, again by ITC.
>
>Since we heard an excellent recording, played on a CD player, the sound was, to
>quote a prominent Valley Girl, like totally awesome. As was the imaging.
>
>Can any of the more technically oriented readers of this net perhaps enlighten
>me as to how ITC can achieve such good sound from the small case describhed,
>and furthermore, what role does the Bass Distortion Reducer play, or how does
>it work?
>
>Bernard H. Schwab
>Siemens RTL, Princeton, NJ

this is pure conjecture, as i have never heard of ITC speakers, but have
heard of speakers that are probably similar.

the Bass Distortion Reducer (BDR) is probably a feedback amplifier with
some form of position detection within the speaker's bass driver.  this
is not saying that the speaker is self-powered.  it controls the signal
reaching the speaker so that the motion of the driver matches that of
the input signal to the unit.  i would guess that the BDR unit fits in
a tape monitor loop or between the pre-amp and power-amp.

3a (a french speaker company) uses this type of approach for two of
their three top-of-the-line speaker models.  they achieve 25-20k
response within 3 dB from an 8"x11"x24" (approx) box with some
sacrifice in efficiency.  being so small, good imaging is easier to
achieve and placement is less critical, although 3a has specific
recommendations for each model.  i like the sound of 3a speakers, but
by the time i could afford the ones i liked, the dealers around here
stopped carrying them, so i couldn't do any listening comparisons.

of course, the people at ITC could have discovered an entirely new
physical principle 8-).

Herb Chong...

I'm user-friendly -- I don't byte, I nybble....

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