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[jeffhtg (Jeff Kenney)]

okay.. so im finally to the point where I can affoard to build my "touring version" of the labs. I remember tom takos had some REALLLLY nice ones i saw online - and im going to try and do something similiar in design with the handles, casterboards.

my main question is.. will standard 4x8 handles in the cabinet cause any noticeble performance issues?? afterall these things DO displace air in the horn!

[Don Snyder]

Hi Jeff,

The LABhorn as built varies from the theoretical curves by as much as 35%. The two black blobs in the sketch below are where I'd put handles. The handles on the right reduces the area by 3% and the handles on the left reduces the area by 12%.

If 35% doesn't screw up the sound, why would 12%?

[jeffhtg (Jeff Kenney)]

I actually want to put handles on the narrow top and bottom (assuming they are sitting so the horn rolls out towards the ground).. Like tom takos box I'm going to build skateboards that pin to the mouth of the sub for transport.. so that would put it in what i assume is the most critical part of the horn path no?

now as far as varies up to 35% - are you referring to improperly built cabinets - or the posted plans?

[Don Snyder]

Putting the handles you've chosen in the first half of the horn length is not wise. What about a handle that doesn't protrude so much? How about Peter Sylvesters use of "grab bars." Penn Fab has a new handle that fits on an edge, and only needs a few square inches of area in the horn.

The 35% error is in the middle of the horizontal flares. These two pieces of wood have compound angles on all sides, and many people freak-out at the thought of making them. Brad Litz's V3.0 requires not two, but four compound angled pieces for his horizontal flare modification. He says fixing it smooths the 40Hz dip by 1 or 2 db. and adds a little to the back volume.

[jeffhtg (Jeff Kenney)]

sweet those corner handles are perfect!

[Don Snyder]

Hi Jeff -- glad you like them.

I think the 1/4 inch covers are total overkill. Bogdan made his covers out of 4mm aluminum (0.157 in) and they work fine. Even 1/8th inch aluminum should work great (and it's a lot easier to find and to cut).