[MOSFET]

Look, I'm sure you're right and that THERE ARE home speakers that utilize
oval speakers. But look at MOST of the speakers out there that use pistonic
priciples to produce sound (i.e. cones), the cones are round to match the
voice coil, which is ALSO round.

To me it's common sense. OF COURSE you want a cone that matches the shape
of the voice coil for PERFECT pistonic linierity.

I was at Best Buy yesterday and the VERY MOST EXPENSIVE ($2,000) speaker
they sold was a tower Vienna Accousitcs speaker that was 4" wide!!!!!
Tweeter difraction IS VERY REAL and the top speaker makers of this world
KNOW THIS.

BTW, I didn't see any oval speakers at Best Buy and Magnolia Hi-Fi the last
time I was there which was within the last couple months (these are two
large retail chains that carry what would be considered low to mid range
speaker brands). What I DID FIND were tower speakers that nearly always
tended to be narrow and deep in an attempt to reduce diffraction.

My only point is that oval speakers would be ALL OVER THE PLACE when it
comes to home speakers if there were no sonic drawbacks to them (or at least
compared to their round bretheren). As you mentioned, these drawbacks
become more pronounced the higher in frequency you go. But you generally
don't even see ovals being used as bass drivers in home speakers. YOU JUST
DON'T SEE THEM.

Now I don't know where you shop that you see all these home speakers
utilizing oval speakers. I am actually curious what that smells like. Do
you have a brand or model in mind that I can find to see this? I AM NOT
trying to challenge you or calling you a liar, I am TRULY curious. As I
said before, on the surface, ovals would be IDEAL in designing the most
narrow speaker you can yet still wanting good bass response.

Again, the fact that MOST home speaker makers NEVER use ovals speaks
volumes. I'm sure there is always an exception, but again, just using
common sense, you want a cone whose shape matches the voice coil for the
BEST linear pistonic movement.

MOSFET

"John Durbin" wrote in message
...
That's simply not true... there have been plenty of home speakers that
used oval cone drivers. Some of the Tandberg teak cabinet models have
them, and I remember a fairly high-end system from Jantzen (spelling?)
that had electrostatics up top and a white oval woofer in the lower
section. That one was someone ahead of its time in that they were
slender towers similar to what people are using for front surrounds
these days, in an era where a floorstanding speaker was more lilely to
be 18" wide and equally deep. At any rate, the shape of the oval woofer
made it a lot easier to get more bass from the system without having to
make it a wider cabinet, just as you theorized below. You may not be
familiar with any home speakers with oval components but they absolutely
exist. I'm sure some basic research on the web would find dozens more
examples.

Frankly, provided the piston is adequately rigid it doesn't matter all
that much what shape it is, up to a point. Certainly lower frequencies
are not affected at all provided the moving element acts in purely
pistonic mode with no gross deflections. Also less symmetrical cones can
be easier to eliminate standing wave distortions on the cone surface,
which can improve accuracy. The technology to control those kinds of
things during driver design through use of tools like finite element
analysis is light-years ahead of where it was when oval drivers were the
mainstay of automotive applications.

You should not use a typical automotive 6x9 as the basis for making
these extrapolated statements. They are generally designed for improved
efficiency & exaggerated midbass output as those are useful in the
average 6x9 application. A component 6.5" driver could have the same
attributes if the designer wanted but would be at an efficiency
disadvantage vs. the 6x9 due to less swept area. You can make that up
with excursion of course but usually that has its own implications in
terms of other non-linear distortions & also added cost. At any rate,
the point is the shape of the cone itself isn't inherently good or bad,
it's more what you do with that shape as part of the overall driver
design.

As to the flush-mounted tweeter on a large flat baffle, a well-executed
design in that form factor can perform very well if the baffle effect is
taken into account when designing the drivers, crossovers etc. You would
have to spend a bunch of money for a slender tower design that will
outperform my JBL L150A's in any appreciable way.

JD

MOSFET wrote:
I felt I should add one point. I mentioned several times that home
speaker
makers do not use the 6x9" size. This is significant and it demontrates
that those who design home speakers know the 6X9" has drawbacks that
compromise sound quality. Why?

Because most mid to high-end home speakers tend to be very narrow (as
narrow
AS POSSIBLE) in an attempt to reduce difraction effects of the tweeter
(it
muddies your trebble, effects imaging, staging, ect). Some speaker
makers
try to get around this by building small pods around the tweeter, OR
putting
the tweeter all by itself on the top of the speaker, OR just extending
the
tweeter out a certain distance. What you WANT to try and avoid at all
costs
is a tweeter mounted flush to a large baffle (something, unfortunately,
that
was NOT put into practice until the 80's as speakers from the 60's and
70's
seem to do EXACTLY that).

The point here is that if 6X9's were just as good at sound quality as
round
speakers, THEY WOULD ALL USE 6x9's as this would create a narrower
speaker
with better bass response (in other words, you would have the benefit of
a
tower speaker (let's say) only 6" wide, yet you would have the bass
making
potential of an 8" speaker). They would jump at the chance to
accomplish
this if they could. But, again, they don't do it for the reasons I've
already mentioned. What MANY home speaker manufacturers do is keep the
width VERY small (some 4" and less for tower speakers) yet they are
quite
deep (12 inches or MORE) to accomodate bass drivers mounted on the sides
of
the speakers (you can get away with this because bass tends to be
omnidiriectional).

Anyway, I wanted to clarify my point about home speakers and the
SIGNIFICANCE of the fact they tend to ONLY use round cones. They would
ALMOST CERTAINLY use the 6X9" if the sound wasn't compromised.

MOSFET
wrote in message
ups.com...

On Sep 10, 8:11 pm, (bob wald) wrote:

ok , just about every connection.

So i was skimming through the posts and noticed that someone had
mentioned that 6.5's are better sounding quality than 6x9's. I would
like to know why this is. As i was thinking about installing some
6x9's in a friends car with boxes to help out with bass and midrange.