Maker Pro
Maker Pro

odd speaker designs...

E

Ernie Werbel

Hi all. I am an electronics enthusiast, and I love taking apart discarded
radios and TVs to tinker around. I have come across, among other things,
something in particular about speakers that seems to stick in my mind for
some reason.

Most, if not 99% of all the speaker cones I have seen, consist of a center
magnet with four spokes extending outward toward the frame in a + shape.
However, in my adventures I have come across, on very rare occasions, some
speakers with only THREE spokes. These are usually small ones, about 2 to 4
inches in diameter. I have seen larger ones with as many as five or six
spokes. I have even come across one with only two spokes, and still another
type with not spokes, but about a dozen circular holes around the magnet.

I was wondring if anyone else here is familiar with what I consider to be
unique and unusual speaker frame designs? Also, while I can see four spokes
as being a good design, I wonder why it is more predominant than say, the
three-spoked frame, which would use less material to fabricate?

Another thing I would like to point out is where the magnet is housed. Most
of the speakers I come across have a drum-shaped housing with the magnet
concealed. I have come across a few with a square metal frame with the
magnet exposed (cheaper to make I presume).

Just thought I would share this with the group. I hope you at least find it
interesting as I did.
 
C

Coyoteboy

Ernie Werbel proclaimed to alt.electronics ...
Most, if not 99% of all the speaker cones I have seen, consist of a center
magnet with four spokes extending outward toward the frame in a + shape.
However, in my adventures I have come across, on very rare occasions, some
speakers with only THREE spokes. These are usually small ones, about 2 to
4
inches in diameter. I have seen larger ones with as many as five or six
spokes. I have even come across one with

I have some monster 15" cones with 6 spokes, rubber protected magnet edges
and a hole through the middle (presumably for cooling?). I know little of
speaker designs.
 
D

default

Hi all. I am an electronics enthusiast, and I love taking apart discarded
radios and TVs to tinker around. I have come across, among other things,
something in particular about speakers that seems to stick in my mind for
some reason.

Most, if not 99% of all the speaker cones I have seen, consist of a center
magnet with four spokes extending outward toward the frame in a + shape.
However, in my adventures I have come across, on very rare occasions, some
speakers with only THREE spokes. These are usually small ones, about 2 to 4
inches in diameter. I have seen larger ones with as many as five or six
spokes. I have even come across one with only two spokes, and still another
type with not spokes, but about a dozen circular holes around the magnet.

I was wondring if anyone else here is familiar with what I consider to be
unique and unusual speaker frame designs? Also, while I can see four spokes
as being a good design, I wonder why it is more predominant than say, the
three-spoked frame, which would use less material to fabricate?

Another thing I would like to point out is where the magnet is housed. Most
of the speakers I come across have a drum-shaped housing with the magnet
concealed. I have come across a few with a square metal frame with the
magnet exposed (cheaper to make I presume).

Just thought I would share this with the group. I hope you at least find it
interesting as I did.
Why not one "spoke?" Less material . . .

There's a compromise between cost and benefit - Ideally the frame
should be 100% rigid and not flex or ring. High quality speakers use
a cast aluminum "basket" - light, very rigid, resists ringing, and
costs more.

With stamped steel, four thinner frame members probably works better
than three thicker ones.

Tweeters and midranges sometimes use a solid basket
 
E

Ernie Werbel

Thanks for the response. I have been taking some time to research this some
more. It seems that the size of the vents behind the diaphragm affect the
airflow as well as the size of the cabinet it is enclosed in. Apparently,
speakers with three arms will response differently than four. Perhaps the
formula using four arms in a frame has been determined to be the recipe for
the best cost vs efficiency in typical designs?

Ernie



default wrote in message ...
 
E

Ernie

Coyoteboy said:
Ernie Werbel proclaimed to alt.electronics ...


I have some monster 15" cones with 6 spokes, rubber protected magnet edges
and a hole through the middle (presumably for cooling?). I know little of
speaker designs.

----- Original Message -----
From: "Coyoteboy" <[email protected]>
Newsgroups: alt.electronics
Sent: Thursday, March 29, 2007 7:41 PM
Subject: Re: odd speaker designs...

I have some monster 15" cones with 6 spokes, rubber protected magnet edges
and a hole through the middle (presumably for cooling?). I know little of
speaker designs.


I came across on the Internet what looks like a scan of a magazine article
about a speaker.

http://www.lansingheritage.org/images/jbl/specs/pro-comp/2205/page1.jpg

They describe vents near the magnet to cool the speaker. The voice coil,
being pumped constantly with current, must get very hot I imagine!

Ernie
 
Top