Karlson's "Fig.6" Reflector - how large and where to focus?

[freddi]

I have an 18" Karlson type with curved upper panel which plays very nice.

Here's a little one with which could use some improvements (don't say pull its wings, etc. 😀)

The recording is analog and of John French so not the cleanest-most dynamic - thing in the first place.

A 10" driver K is about where the power starts. The slotted pipe tweeter can sound very good.


I would assume the focus of the reflector should be "outside" the aperture a bit.

Karlson Coupler with Eminence Delta Pro 8A speaker - YouTube

 

[GM]

Had to look up what you're referring to, so responded here: Karlson's Fig. 6 Curved Reflector - who here is good at ray tracing ?

 

[AllenB]

What kind of raytracing do you need?

 

[Patrick Bateman]

I've tried a bunch of different acoustical reflectors, and these have worked the best for me:

https://www.researchgate.net/profil...g-a-version-of-the-Point-to-Arc-Generator.png

A 3D printer is a must for something like this. I nearly cut my thumb off, trying to make one of these out of wood using a router. It's actually the reason I got into 3D printing.

 

[freddi]

Gentlemen - the WKF ("World Karlson Federation" 😀) needs your input on what "might work" subjectively to focus (in claims) some of the reflections from the upper half of the front out of the box and away from the cone.

Hopefully the curved reflector does not make response worse. (I think it could work both ways - worse if unlucky)

Two and 3 panel approximations of the curve are welcomed as save labor and expense.

I would like to include a "K-tube" slotted pipe tweeter mounted through the reflector/port panel and would go with a 10" woofer (12" at most w. Kappa12a) and 1.4" compression driver for the K-tube.

The design should be compact - retain some "hit" and punch clearly..

FWIW I could throw away most of the upper chamber so it would be like a mini Metro T15 - or my KUBE12 - that probably would make the low end approach bandpass sims - but it might not sound as cool -

An advanced K-builder likes a taller aspect. Again I think that may or may not work better than the original aspect for a given bulk.

 

[freddi]

Look at Karlson's "X15" which applied a 3 panel approximation of patent 3540544's Fig6 reflector. Where does it focus?

With this aspect of 28"H x 20" wide by 15" deep, is there an improved front cavity shape? (not fair to say "none at all" ...😆

 

[GM]

Hmm, if I'm following you, then rather than the original's flare that goes to a very high frequency, truncate it to a ??? Hz 'throat' based on the speaker's baffle step/whatever and start a new horn flare designed for this higher BW, i.e. makes it look like a vertically oriented HR simmed compound horn's schematic since this is what the original was trying to somewhat mimic.

 

[freddi]

hi GM- - X15's slot in its first half of travel coming down from the top, opened a bit faster than a pure radial arc. That may have been partly for tonal balance and part for clearing the K-tube - although the first X15 tweeter was a wood mini-klam with 3" paper cone driver.

 

[PeteMcK]

Some of the early French 'Epsilon' designs might provide some inspiration:
https://www.inner-magazines.com/audiophilia/elipson-a-loudspeaker-that-made-new-music/

 

[GM]

Greets!

True, but what does it have to do with my statement, attached suggestion? Its top/bottom of course would be closed off by the cab's end plates.