jmanso wrote:
Grant Bunter wrote:
jmanso,
How wide is your cab?
It's around 52 cm. (50 cm wide plus 2x 12mm from the wood)
which google tells me it's about 20.4724 inches
I wish I had asked earlier then.
From what pictures I can see, you have nowhere near enough braces in your cab.
From My plans:
Braces connect the panels. Made of ¼ to ½ inch plywood, they are nominally spaced six to nine inches apart.
For a cab around 20 inches wide, you should have 1 x panel 2-6 brace, 2 x panel 3-5 braces, 2 sets of panel 5-8 braces (4 braces) and 2 sets of panel 9-6 braces with one crossbar.
I know for certain you only have one panel 9-6 brace and crossbar, so I assume you haven't put in the correct amount for the rest of the cab.
You might think that the cab is solid as it is, but any or all of those panels can flex, and when they do, that robs you of 3dB in output.
To give you an example of what losing 3dB means, if you are building
2 cabs and not properly bracing them, that would be the same output as
1 cab properly braced.
If you haven't put your final side on, you can fix this, with difficulty, but the hardest place to fix will be the panel 3-5 braces...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...