Exciting new line of fullrange drivers from Feastrex

[bappe]

Could it be a 100% Permendur Naturflux field coil sort of driver:-)

BR,
Anders

[Bunpei]

Originally Posted by talawalla

Kindly tell us a little more about the changes from the standard or previous Type III that make the Type III CW driver unique.

Originally Posted by bappe

Could it be a 100% Permendur Naturflux field coil sort of driver:-)

First, I should correct the model name.
The correct one is "Dimension-5 Exciter Type III CW Memorial Model".

This type III does not have a Naturflux type round yoke.
It has the same cylindrical yoke as the previous type III has.

As a matter of fact, Hal has not disclosed enough details about the Type III CW Memorial Model. He just told me that they introduced well-experienced materials for wrapping(?) and finishing a field coil and for lead wires of the coil. Can you guess what they have made?

Bunpei

[bappe]

Since the motor in the field coil units are allresdy looking like the old WE ones, one guess would be that Hal has taken it one step closer to the original. Maybe some washi paper has found its way into it? Copper foil and Washi paper?

BR,
Anders

[Bunpei]

Originally Posted by bappe

Maybe some washi paper has found its way into it? Copper foil and Washi paper?

I think it's a pretty close guess. I hope Hal will explain details later.

Bunpei

[mluckow]

I'll be looking forward to hearing it.

Mike

[Phil Townsend]

New OB in the works... f
Feastrex 5Dnf
Altec 416 alnico
Behringer Xover (rebuilt etc)

Plywood proto to start with...

[mluckow]

Phil,

So, you decided to go with the Behringer DCX2496 Ultra-Drive Pro? I'll be very interested in hearing how you like it since that's how I'm leaning, too.

How many layers of plywood are you going to use for your prototype? And what dimensions?

Mike

[Phil Townsend]

There will be 2 layers of baltic birch 1.5 inches total.
40 inches tall
24 wide
Great Plains 16" Altec 416 Alnico 16 ohm


I'm listening to the 5Dnf in their Makio 1 cabs..
They are being driven by Nelsons First Watt J2. Yes, this is a very happy combo...The J2 has PLenty of power to drive the 5Dnf to the prizes. The bass in the 5Dnf has blossomed. And still it seems that I have not given up ANYTHING in the mid range. I was thinking the that my 45's midrange would be missed. IT IS NOT!
About the only thing I can say to the contraire is that the J2 does not have any heaters.
The J2 has about 150 hours on it. Its getting time to pop the lid and see what those Pass Boys have done.

My only serious question is... When will Digikey carry SemiSouth ? SemiSouth sure does make fine sounding three legged monsters. Still, I suspect they have zero sense of humor unlike their tubed brethren.

[Phil Townsend]

No, One layer of plywood (3/4") then on layer of Trex (1.5") Total 2.25" thick. The layers will be bonded with Green Goop. The Trex is recycled plastic/wood mix. One board of this stuff... 10 feet long 5.5" wide and 1.5" inches thick Almost takes two people to pick up one board. It is really heavy and very very dense.
Trex is used for decks... It will Never chip check crack or pucker.

Trex Physical & Mechanical Properties

[Bunpei]

Originally Posted by Bunpei

The tallest pair is Tanaka's Tube (a.k.a. Nessie-J, our nickname is a “Chimney Box”), Version 4.

Construction activities for long tall "Tanaka's Tube" are presented in Feastrex BLOG page. I will introduce this topic adding my personal comment.

Mr. Tananaka, a wood & urushi crafter of Japanese traditional style, is also a typical audiophile and has been concentrating on producing Nagaoka Nessie style enclosures in these years. In this version, he selected a "Russian Birch" plywood.


Though some people, including Dr. Akiyama of Feastrex Company, refer the type as a "back load horn", Mr. Tanaka and Bunpei regard it as a simple (not tapered) "quarter wavelength tube". Its effective tube length is 300 mm and this leads a resonant frequency 28.3 Hz (at 15 degree centigrade). Mr. Tanaka's objective is to prove that a 5" full-range driver can produce enough bass as far as a well-matched box is given. To verify this, he always checks his system by playing "Saint-Saens Symphony No. 3 'Organ'".

The tube was constructed in the following manner:
1. A back-tube part is on a bench.
We can look at a square hole where sonic wave goes through from a front-tube part.


2. A front-tube part is stacked on the back-tube part.
Two parts are tied up by screws inside.


3. A Feastrex 5" Naturflux Exciter PIP driver is mounted.
The unit is not fixed on the front baffle by screws. The diameter of the baffle hole is the same diameter of the basket face.


4. A long bolt screwed into yoke locks the driver from backside.


5. A back-lid for the back-tube is set.


6. An "Iron Dead Mass" for the driver is inserted from the back-tube side.



7. Hal watches Tanaka's cabling work.


8. A back-end of the dead mass and a connector panel


A pair of Tanaka's tubes can reproduce deep bass of organ instruments very well. However, pros and cons. This tube structure is good for a bass of resonant nature in general. As for such a high-speed bass from drums, of transient and decaying nature, Bunpei thinks the structure does not fit well. Moreover, positioning and size of listening room is very critical for these tall boxes because bass is emitted from the top of the "Chimney". The bass should be diffused smoothly over the room.

Bunpei want to emphasize that Tanaka's tubes can play a cello, violin, sax in a very attractive mood. A woody sound mathes very well.

Bunpei