Aluminized Mylar As replacement for Carver Ribbons

[kathiezman]

Question. The Carver ALS I have utilize two aluminized traces in the Kapton ribbons. The current flows inside the assembly of the driver up one trace then crosses over at the top and flows down the other trace to close the circuit to the amp. (Flows up and back down inth eassembly)

What if a single layer of continuous aluminized mylar were used as the diaphram? Aluminized mylar of maybe .0005" thickness? Similar to a space blanket. Or the material used in floral shops. The current could flow into the ribbon at the bottom of the ribbon utilizing both connectors as the leads in, flow to the top out both leads, and then the circuit would be closed outside the ribbon assembly by wire from the top of the assembly

Instead of a flow up and then down within the assembly, the flow would be up and out (one way)through the asembly, and back to the amp.

Could this not work?

[srinath]

That will result in the whole diaphragm getting shoved sideways instead of pleated sides moving towards and away from each other. I think.
Carver ribbon ... not familiar with it.
What are its dimensions ... the ribbon's dimensions.
Continuous ribbon will need magnets side to side. Ribbon has to move front and back.
Cool.
Srinath.

[kathiezman]

Thanks for the reply:
The Carver "ribbon" is not a true ribbon. Kapton. Two traces of aluminum applied by vacuum depositon. The traces are .312" wide and spaced .750" appart. Ribbon is maybe 5 inches wide stretched over a 4 in frame.
The ribbon is held into the enclosure by tensioning along the entire edge. Top sides and bottom. That is to say that there is no loose edge as in a true ribbon.
It is really more like a diaphram that would be used in an electrostat except instead of the transformers and current deflecting the diaphram through a static field.... the diaphram in this case is placed in proximity to 3 strips of neo magnets. The actual traces fit between the 3 sets of magnets. And of course the current flow through the traces interacts wihtthe static mag fields imposed by the magnets and moves the diaphram.
It is a pull system not a push and pull. Magnets are on one side of the diaphram only.
I am wondering what the effect would be to run the current going only one way through the mag field instead of in up across and back down the other trace.
If you know it would help a lot. I am tired of having this repaired inadequately. If you don't know what the efect would be, or if the aluminized mylar would survive...maybe you know someone who would know?

[srinath]

That is such a cool description. Tensioning them is easy, magnets are easy. I guess I need to google up a picture. BTW I love the ribbon or other un conventional tweeters. They really really work.
Cool.
Srinath.

[tinitus]

Originally Posted by srinath

That is such a cool description.

Describing a "planar"

[kathiezman]

The question then is:
Will using the entire surface of the aluminized mylar as the conductor work. Will it conduct enough current?
And what wil be the effect of running the current only one way throught the magnetic field instead of in and themn back out.
It seems to me that with the current design with two traces there is a potential for the two linear halves of the diaphram to be slightly out of phase in motion. The extreme speed of the signal through the ribbon is what negates the sonic effect of this phase shift.
So I would think that really a single continuous conductive surface of sufficient lightness and durability. Like aluminized mylar...should actually work better?

[Planerguy]

Correction - the Carver as well as the B&G drivers are in fact push-pull. The magnets are both in front of, and behind the planar ribbon. Most of the magneplanars on the other hand are made with the magnets only in front of the planar driver. Their most expensive speaker uses both push-pull and true ribbon design.
The design mentioned here in the question above would work, However there would be problems. First, the moving mass would be greatly increased, causing lower efficiency and more then likely an early roll off on the high end. The impedance would also drop quite low, perhaps a to about 1/4 ohm? All in all, not a good idea I'd say.

[srinath]

Oh yea some of the infinity Kappa early series, maybe the 5.1 or even earlier would nearly drop to under 1 ohm. That was with EMIT and EMIM and a woofer. Can you say fry my amp please.
I suspect that lead infinity to dump the EMIM.
Cool.
Srinath.