Incoming...811b horns without vanes

**BillWojo** · October 4th, 2016, 11:24 PM

GM, as a machinist with access to a shop I'm curious as to how you aligned the conical flare to the horn casting itself. You said you honed the interface between the driver and horn right into where the wave guide joins the square flare.
I would imagine that the phase plug and screen would need to be removed to align the driver to the best position on the horn casting. A flex hone could be used to blend the transition.
Installing a couple of roll pins from the horn side would help realign it after it's taken back apart for cleaning and reinstalling the phase plug.
The face of the driver is machined in a lathe when manufactured so it should be very flat. The ends of the horns could be fly cut in a Bridgeport pretty easily. That would give a decent sealing surface.
Looking at one of the loose horns I can see that the 1" bore doesn't match the gasket all that well, the casting is slightly bigger in certain spots, mainly along the sides with the seams. Glass beading the throat area to get to bare metal and building up with Devcon aluminum putty would allow one to get it to a point that it could be blended perfectly from the driver to well into the throat of the horn.
I can see a lot of room for improvement, it's a matter of does all the work justify the sonic difference that I might hear.
How did you go about matching yours so well? Maybe I'm just over complicating things.

BillWojo

**SD-50** · October 5th, 2016, 02:34 PM

Originally Posted by Elitopus1

Are you guys using a single layer of wax paper or multiple layers?

I use a single thin layer, but thinking about trying several layers, or a single thick one.

**Elitopus1** · October 5th, 2016, 03:04 PM

Originally Posted by SD-50

I use a single thin layer, but thinking about trying several layers, or a single thick one.

Ok thanks. Looking at my 802D and Emilar EH800 horns they both look pretty flat on the mating surface. It does make sense that I wouldn't have to use a thick cardboard gasket.

I looked in the horn throat and with the cardboard gasket you can see a big gap between the horn and driver. With a thinner gasket or none there is no gap at all.