Altec / JBL project

[Ben Clarke]

Cool. Seems like you could fine-tune bass response by varying the height of the feet, as that area is functioning as part of the horn path.

[yggdrasil]

Cool. Seems like you could fine-tune bass response by varying the height of the feet, as that area is functioning as part of the horn path.

Yes I think so. The feet are 13cm high in front, and 11 cm high in the back, so the speakers are tilted 4-5 degrees backwards. The opening area between the feet in front is slightly larger than the mouth of the spiral.

[yggdrasil]

Here's a few pictures of the inside of the cabinet. You'll see the spiral horn lika a staircase on one of them.


To make the spiral horn I cut about 40 small triangular pieces of MDF, which I glued together. Then I took a piece of stiff cardboard and turned 2 times around it. Fast and not aestetic but it works very fine.
You'll also see that the top piece is extended to the cabinet side to make the construction more robust.

[Ben Clarke]

Wow. Ok, I didn't see that from the drawing. Ingenuity at work. I wonder if a piece of PVC pipe might provide a more rigid boundary for the horn path.


This is unlike anything I've ever seen!

[Steve Gonzales]

That is a super cool way to tune an enclosure! OUTSTANDING WORK!!

[spkrman57]

I like the unique-ness used there.
Ron

[reVintage]

Hey Panos and all others,

I am lifting this ancient thread as I am currently designing a midbass prototype.

To try the concept I have a pair of Lowther style midrange horns lying in my garage. Same as my friend Bo Hansson of Rauna/Opus3 uses in his Chaverex system. Will use them together with a pair of 414-8A also in my stash.



Will come back when I get home from work to show some sims of a midbass to be be used from something like 100Hz. No shelving but due to the nature of 414 restricted bandwith upwards.