Hello,

I'm having a problem with a pair of speakers I own whereby the mid-range
cone appears to cut out. Before I attempt to explain, let me point
out that I don't know a whole lot about what goes into a speaker box, so
please go easy if I omit important information (and please correct my
terminology).

My speakers are prominently labeled HED, with the back panel expanding
that to High Energy Design and also containing the name Carwin-Vega,
apparently the manufacturer. I couldn't find a model number anywhere,
but I might not know where to look. The connection panel on the back
contains two pots, one for mid-freq and the other for high-freq, with a
range marked 1-5. It also has a reset button. The box contains a 12
inch woofer, 5 inch midrange, and 2.5inch tweeter. I'm told these were
rather expensive in their day (1970's?), and indeed I'm pleased with
their sound. I would be interested if anyone could tell me more about
these speakers, though that's not my main question.

It might be relevant to mention that the setup is powered by a Yamaha
RX-V495 receiver, and that the problem manifests itself apparently
regardless of input source (CD, FM, decoded MP3) or type (analog or
digital).

The problem is manifested by an intermittent loss of tone quality in the
mid-range (to my untrained ear). I have isolated this apparent cutout
of the midrange cone to one speaker box; the other is unaffected. It
doesn't appear to be affected by volume, and the connections are sound.
I tried hitting the reset button on the speaker, but that hasn't
helped. I also adjusted the pots, again to no effect. I suspect that
something may be wrong with the crossover circuitry (presuming there is
a crossover), but I don't know how to proceed with the diagnosis.

If anyone could provide me with some background on these speakers and
what could potentially cause this problem, I would be appreciative.
Specifically, what are the functions of the pots on the back of the
speakers? What does the reset button do? Could a bad cap be causing
this problem, and should the caps be replaced on these 30 year old
speakers?

Thank you for relieving my ignorance.

Corey

Corey Keasling wrote:
Hello,

I'm having a problem with a pair of speakers I own whereby the mid-range
cone appears to cut out. Before I attempt to explain, let me point out
that I don't know a whole lot about what goes into a speaker box, so
please go easy if I omit important information (and please correct my
terminology).

details snipped

Thank you for relieving my ignorance.

I retract my gratitude. Instead, I will thank you for nothing.

Corey.

"Corey Keasling" wrote in message
...
Corey Keasling wrote:
Hello,

I'm having a problem with a pair of speakers I own whereby the mid-range
cone appears to cut out. Before I attempt to explain, let me point out
that I don't know a whole lot about what goes into a speaker box, so
please go easy if I omit important information (and please correct my
terminology).

details snipped

Thank you for relieving my ignorance.

I retract my gratitude. Instead, I will thank you for nothing.

Corey.

Perhaps you got no response because no one on this forum happens to have any
useful knowledge of the speakers you're asking about. Additionally,
intermittent problems in electronics are extremely difficult to diagnose,
especially in the third person.

Corey Keasling wrote in message ...
Corey Keasling wrote:
Hello,

I'm having a problem with a pair of speakers I own whereby the mid-range
cone appears to cut out. Before I attempt to explain, let me point out
that I don't know a whole lot about what goes into a speaker box, so
please go easy if I omit important information (and please correct my
terminology).

details snipped

Thank you for relieving my ignorance.

I retract my gratitude. Instead, I will thank you for nothing.

What, you think, in a free, public forum, you are somehow ENTITLED
to a response?

There are a number of technically competent people who contribute
to this forum without either expecting or receiving compensation of
any form in return. They (we) do it as a favor to those, and do it
when time and pressure from clients and jobs allow. It's often very
gratifying work, and often quite a hard job when it comes to explaining
some esoteric physical principle now and then. Despite that, a lot of
us do it because we enjoy helping people learn.

Then, someone comes along who DEMANDS that we answer their question
and when they don't get the response they want WHEN they want it,
they respond with "I retract my gratitude. Instead, I will thank you
for nothing."

Well, you may thank us for nothing, because after a petulant, demanding
comment like that, nothing is likely what you will get.

You're welcome, by the way.