Baffle width for Cantilenas

[jhd]

I'm thinking of building a pair of Paul K's Cantilenas. Paul's original design looks like this:



I'd like to make them as a rectangular box. But if I do, I'm not sure how to modify the baffle. As you can (maybe) see from the image, the face of the speaker is 9 7/8" wide, but it has 3/4" red oak side panels on either side, making the full width of the speaker 11 3/8". But these side panels are recessed a bit and don't extend all the way to the front.

Given that the face is 9 7/8" wide, but the full width (including recessed side panels) is 11 3/8" wide, which is the "right" width to use to keep the speaker behavior the same? What would be the difference between building this speaker at 9 7/8" wide vs. 11 3/8"?

Thanks!

[Pete Schumacher]

Re: Baffle width for Cantilenas

I'm thinking of building a pair of Paul K's Cantilenas. Paul's original design looks like this:



I'd like to make them as a rectangular box. But if I do, I'm not sure how to modify the baffle. As you can (maybe) see from the image, the face of the speaker is 9 7/8" wide, but it has 3/4" red oak side panels on either side, making the full width of the speaker 11 3/8". But these side panels are recessed a bit and don't extend all the way to the front.

Given that the face is 9 7/8" wide, but the full width (including recessed side panels) is 11 3/8" wide, which is the "right" width to use to keep the speaker behavior the same? What would be the difference between building this speaker at 9 7/8" wide vs. 11 3/8"?

Thanks!

I really doubt that there would be a noticeable difference with the slightly wider baffle, given where the woofer crosses to the mid. The real difference is going to be the behavior of the mid and tweet on a squared off baffle compared to Paul's circular top. Diffraction related changes will be much more pronounced up there because of the shape difference, not just the slight size variance.

Nice sounding speakers too.

[jhd]

Re: Baffle width for Cantilenas

Thanks, Pete.

Does anyone know if the Cantilena design takes into account diffraction behavior of the rounded top? And generally, wouldn't diffraction be less of a problem on a rectangular baffle than a curved baffle, since the diffraction would be less focused on a single frequency (or close range of frequencies)?

[rickcraig]

Re: Baffle width for Cantilenas

Thanks, Pete.

Does anyone know if the Cantilena design takes into account diffraction behavior of the rounded top? And generally, wouldn't diffraction be less of a problem on a rectangular baffle than a curved baffle, since the diffraction would be less focused on a single frequency (or close range of frequencies)?

I designed the crossover and a rectangular baffle would be no problem.

[Paul K.]

Re: Baffle width for Cantilenas

I'm glad that Rick chimed in. I've been asked by several people over the years interested in building the canTiLenas but wanting to make the top rectangular since it would be much easier. Rick has assured me there would be insignificant negative effects doing so. I do believe the effects would likely be measurable, however, but only "golden ears" could hear them. :D
Paul

Edit: Regarding the baffle width. The interior MDF sides are only 1/2" thick and when combined with the 3/4" oak sides, makes the cabinet quite rigid. If you want to delete the added oak sides, you'll need to use 3/4" thick material for the sides, keeping the interior width as I designed/built it. This will obviously increase the final baffle width another 1/2", but that, too, will not negatively affect the performance. I used a 1/4" radius round-over on the baffle, but making it larger, either 1/2" or 3/4" would further mitigate any effects from this wider baffle.

[braves]

It seems a long time ago topic, but I think there might be somebody still can answer some questions.

Paul made the ML-TL design with an opening on its back. But how about the opening's size and its height?
Thank you in advance.
George

[Paul K.]

George, since this is an ML-TL it has a port, not just an opening, on the back panel, and the dimensions of the port I used were 1.75" D x 2.25"L. The center of this port is 13" above the internal bottom of the cabinet, and the "bottom" of the cabinet is the top of the base assembly (the crossover assembly is mounted upside down in the base).
Paul

It seems a long time ago topic, but I think there might be somebody still can answer some questions.

Paul made the ML-TL design with an opening on its back. But how about the opening's size and its height?
Thank you in advance.
George