completed doom horns

Having found a new workshop a few months back the doom horns have finally been finished, built from 13mm ply for the horns and 18mm for the rest. 

The ply for the horn segments was laminated in a vacuum bag, much fun creating a former that withstands the pressure which iirc works out at about 1200lb/sq inch.

really pleased with how the pieces came out, very negligible springback and an almost invisible glueline.

Once the stock was laminated to the curve it was time for the joy of working out the curved compound mitre angle, and then how to go about cutting said mitre.

For this pair I ended up using a router jig, bevel bit and then spokeshave to get the angle/s correct, there are more ideal ways of doing it but for the first build this way seemed easiest.

 

Getting the bits into the clamping jig/doing the glue up was a fair amount of hassle, the mid horn is modular for transport so is constructed in two halves.

The halves came out pretty well, not entirely perfect but with a little refinement of the method and a composite lamination utilizing some nicer material on the faces leaving them with a wood finish would be possible. 

With the horns being modular the driver for the mid is housed in a seperate module that clamps onto the assembled horn

transitiony bit and a lick of paint on the horn segments

Whilst it would have been nice to leave the horns unpainted, there is much to be said for them being so black that no light can escape from them.

Still need to make the phase plugs but other than that they're up and running, have moved back to a 1" on the top end as the 4590's were slightly overkill and too big of an object to have mounted co-axially. 

James made up some metal tilt frames which have worked out pretty well, not too heavy and fold flat for transport. As with the method of joining the components together, there is still some room for refinement, but i think the best way to decide on the way forwards with that is to use them for a while and then see which parts of the process cause issues. Even in their current slightly clunky state they only take about 10 minutes each to construct.

Had the system out in the gramophone disco tent at boomtown, sounded well with their pre 60's music policy, didnt get any photos due to the dingyness of the tent and phone playing up which is fairly annoying... took a few a couple of days before setting off, but they were also taken in a dingy location, still gives a vague idea...

the sheffield drum record through these is pretty amazing/borderline acoustic warfare.