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Serge Auckland Serge Auckland is offline
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Default Do Old Bose 901 II's Need an Equalizer, Or Can't We just Turn Up Our Receiver's Bass and Treble



"Tom" wrote in message
ups.com...
Hello all,

I was lucky enough to inherit a pair of 901 II in Tucson, I am 67,
mainly a lover of classical, and bought my AR2a's unfinished while
stationed at Offutt AFB, NB in 1962. Alas, there was no EQ

I have stayed with the classical since as a listener -- for pure
passion, meditative clarity, and support. But I fell away as an
audiophile, partly because some historical recordings of terribly bad
sound can still be thrilling. E.G, the Berling Symphony Orchestra
playing Bruckner's 9th over the radio in 1944 -- an unfinished
symphony by a dying composer, played in a dying Germany.

The 18 drivers are in perfect shape, and they look as if they were
recently refoamed, All 18 play approximately the same as measured by
the hose-in-the-ear stethoscope.

I wrote to Bose, and they answered the next day (see below.) They said
I must find a Series II EQ. Response curves werethe same for I's and
II's, different thereafter. My II speakers are acoustic suspension --
sealed box expecting plenty of amplifier power to move them and
compress the air in the box, while smothering backwaves. I am guessing
they caved to the "no highs, no lows; must be bose" cliche and ported
their boxes to shore up the base while stonewalling the boomy problems
bass reflex can bring. OK, I admit I am guessing on that, but what
else could those nifty tailpipes sticking out of the reflector side be
for?

Anyway I began looking for a used E in the Q II, but eBay sellers
don't know anything about complex electronic hardware, so it's a crap
shoot.

I want to use these speakers in the home I am building, more
specifcally in the great room (30'L x 20'w x 12' h.) They were such an
icon in my youth. I am not going to mod the boxes; I will try the EQ,
and will thoroughly tes repositioning them. However, in looking at the
EQ II,s pics it would appear to control the audio curve just as do
ordinary bass and treble controls on my receiver; why can't I use the
latter and forget the questionably-functioning 30-yr EQ I'll end up
with?

Thanks,
Tom Mitchell
Rio Rico, AZ


There's no absolute need to use a Bose equaliser, but as the 901s very much
need equalising, I doubt whether the tone controls will be able to do the
job, as the curves you can generate with a tone control are unlikely to
match the Bose curves.. You can try it with your receiver's controls, you
won't do any damage to the 901s or the receiver. If you can though, buy a
Bose EQ, alternatively, a good graphic EQ could be set up to do the job. If
Bose are helpful, can they at least give you the EQ graph that their EQ was
set to? This will allow you generate a similar shape with the graphic EQ.

Finally, if you have been used to more modern 'speakers, you may find the
901s horribly coloured and the direct/reflecting mode of operation provide
you with very poor stereo. The 901s were classics, but even at the time were
something of an aquired taste, one which we never aquired this side of the
pond, preferring a more "natural" sound with precise stereo imaging.

Good luck anyway.

S.

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