Cornwall improvements

[Colin]

anybody try other 15" woofers in their speaks?

what about reinforcing the interior?

[WMcD]

It is unlikely that a driver with other parameters is going to yield improved results.

In an automobile, you can install a more powerful engine, and get more acceleration.

However, it doesn't work like that with speakers. There are interactions between the speaker T-S parameters (Qts, Vas, Fs) and the box volume and port. The trick is to get them all working together correctly. It ain't simple.

Putting in a different speaker is very likely to make things overall different. But "different" is unlikely to be "better" without a lot of calculations.

This is pretty much engineering fact.

- - -

A lot of people endorse cross bracing. The theory is that the box is flexing, and should not. Whether the Cornwall has such a problem to any significant extent is a matter of conjecture. "Tighter" bass is often reported by tweekers applying bracing to any project.

In this matter, engineering theory favors bracing and I'm not telling you theory is not in your favor. On the other hand, the magnitude of the problem, and solution, may be more imagined than real.

Regards,

Gil

[Jim Cornell]

WHY, would you want to do this? Need a woffer? I have a spare!!

Regards Jim

[Pete C]

That audioreview site had a post by someone who liked the way it sounded with a 60 lb. bag of sand on his Cornwalls. I guess that's a way to reinforce the walls.

Oh. I guess it was BobG's suggestion.

[J M O N]

I think that cabinet bracing is a good thing, especially with such a large cabinet such as the Cornwall. However, remember that by adding internal bracing to a speaker, you are also changing the internal volume of the speaker. This changes the speaker. How much will this change the speaker? I don't know, but the more/larger braces you put in, the more you decrease the internal volume of the speaker.

In bracing an existing speaker (i.e. not designing and building a speaker from scratch where you can compensate for the added bracing), it would be better to brace it from the outside of the cabinet (at least theoretically). The idea to add 60 lbs. of sand on top does just that, it "braces" the top of the speaker. However, you still need bracing for each of the other sides. One idea I suggested a while back, to test the benefit of bracing, is to get a large clamp(s) and clamp the sides of the cabinet (i.e., reduce the flexing of the cabinet walls). Just make sure the clamp(s) do not have any loose parts that will vibrate and make a racket. This is one method you can use to see if bracing will give you the benefit you were looking for, without actually making permanent modifications. It's also a method that will not change the internal volume of the speaker.

[Colin]

thanks - I liked the 60 lbs of sand that I wrote about, but now I use two paving stones of 20 lbs. each since they look better - tightening the walls from the inside sounds like a good idea - but I do not think I will go in that direction - I was really thinking about woofer's with better features - larger magnets perhaps, things like that ...

[Pete C]

Ah! Same Colin... Sorry I didn't notice it when I reread the post over there.