[mas]

I've finally started my OB -5 build. I have completed the cut list (mostly), but need a question answered before I can continue. Do the interior braces (c and d braces) need to have the cutouts rounded over? The A/V-3 braces all required this, but I think the OB-5's  do not require roundover because the lower cabinet is for low frequency only (<200 HZ). Thanks in advance!

[Daygloworange]

mas,

It's a good idea to round them over. There is quite a bit of airflow going on in there. It will minimize turbulence.

We do it it to all of our braces.



Cheers

[mas]

Thanks Dayglo. To be honest, I was hoping someone would say I didn't need the round-over, since I had already glued two in! I was disappointed enough that it slowed me down, but I am making sawdust again. It turned out OK, since I had misread the size for the top for the "simpified enclosure", which was better to discover sooner rather than later.

I have a different question about the size of the "Bottom type A" brace.  I am building the simplified OB-5 cabinet, and I can't figure out how the width of the "Bottom type A" brace can be 8", because that would mean the sides should not be 31.25" long.  I'm thinking that the brace should be 13.25" x 6.5", allowing a press fit (no glue, held by screws into brace B and E)  between front sides and back. 

[Danny Richie]

You are right. The side measurements should be 30.5". My bad.

[mas]

Thanks Danny. I think I will stick with my approach. No cut out area, just a press fit - otherwise removing the crossover would require ruining the veneer.

If I did use a cut out area , wouldn't it be 11.75" x 6.5", rather than the 12" x 6.5" specified?   

One more question about what I think is a typo. Again for the simplified enclosure, you advise adding a 1/5" mdf layer to the standard 3/4". Should that read 1/4" or 1/2"?  I  think I am going to use 1/2" plywood glued to the  3/4" mdf, with the mdf in the front. That way the roundoff of the open baffle woofers will show the plywood rather than mdf.

[Danny Richie]

If I did use a cut out area , wouldn't it be 11.75" x 6.5", rather than the 12" x 6.5" specified?

Yes.

One more question about what I think is a typo. Again for the simplified enclosure, you advise adding a 1/5" mdf layer to the standard 3/4". Should that read 1/4" or 1/2"?

 

That one I corrected a long time ago, but forgot to re-upload it. Yes it should be 1/2"not 1/5".

[Cacophonix]

Thanks Danny. I think I will stick with my approach. No cut out area, just a press fit - otherwise removing the crossover would require ruining the veneer.

Thats exactly how i'm doing my OB5.