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      >>>>> WORK IN PROGRESS <<<<<

Part Six

Construction Photos

Please see Diffraction Wedge photos below. These were made from 2mm thick heavy duty vinyl tile. The type used was designed for floors such as factories or commercial kitchens. Cut with a straight edge knife (I used a guillotine), edges filed at appropriate angles for a snug fit, superglued together, then covered with a thin black felt to cover. Make sure that the centre square hole, that the felt overlaps the inside edges by 2-3mm, so that the holes looks slightly smaller after the felt has been glued on. Use craft glue from the same craft shop that also sells the felt. The felt comes in many colours, so if you want something more garish looking? Up to you.

Later, will post actual dimensions of cut vinyl here, to assist making your own.

It may be a good idea to use some Blue Tack to hold the wedge in

The Photos below relate to older Mark 1 and Mark 2 versions:

(Mark 3 Boxes have less cavity recess and flush mount Tweeter)

Finished Boxes

Plain mat Black Acrylic paint - spend your money and you could get them done by a pro.


 

Paint Job - Pic 1

 

Paint Job - Pic 2


 

Individual Drivers - each wired through the Port - Testing Only

This shows there are three sets of terminals - two top drivers in series and two likewise at the bottom.


 

1 Metre Measurement - this is ON axis


Damping is identical for ALL versions:

 

Wool/Dacron Bats Prepared

On the Left - five pieces to suit one box complete. Larger piece on the Right is before cutting.




 

The Photos below relate to older Mark 1 and Mark 2 versions:

Diffraction Wedge - before Felt is applied

 

Rear of Diffraction Wedge

Note that edges are filed for flush mounting - 3mm MDF could also be used.


 

"Yes it fits, now time to apply Felt."

Note that the angled filing means all edges are flush.


 

This is how it looks finally

This is thin 'Craft' felt and glued on.

 

Next: Gathering Acoustic & Z Data

 


Total Design Responsibility, Joe Rasmussen of Custom Analogue Audio & JLTi

Part Financial Sponsor & Prototype Box Construction, Bernard Chambers of Sutherland

Sounding Boards, Michael Lenehan of Lenehan Acoustics & Brad Serhan of Orpheus Loudspeakers


 

Send mail to joeras@vacuumstate.com with questions or comments about this web site.
Copyright © 2003-10 Joe Rasmussen & JLTi
Last modified: Friday February 19, 2010

Just had a terrible thought. If "intelligent design" is unscientific, then who will design our audio equipment?