Mini Project: Visaton waveguide on JF-1204F

DrewsBrews

Just playing around to see what it can do, as it looks like they respond pretty well to the SEOS profile. This should be a pretty easy retrofit.

Made some gaskets. The~1/16" thick foam is just slightly thicker than the depth stops around the diaphragm screw holes. Should do fine to lightly compress the foam to make a seal. While the stops keep everything in parallel alignment.

Found some scraps that should suffice to make backer plates to sandwich the tweeter in place. Just need to see if I can locally find some all-thread or really long screws in that small thread size (maybe 6mm?) that will go from the backer plate to the screw threads in the waveguide.

a4eaudio

The Visaton bolt-holes are size 4M and Lowe's has them in several lengths, and I would bet that Menard's does too.

I used the disc left over from my baffle cutout as my back plate (and sprayed it with some black primer because it is important for the crap inside the box that no one will ever see to look good, LOL).

1) I had some thin neoprene foam I used as gasket, but I like the hobby foam you referenced and have a big sheet of that coming from Amazon tomorrow or Monday for future projects.

2) I put some gasket tape I would use on a woofer on the side of the backer plate that presses against the tweeter, just to relieve a little of the pressure in case I was too overtighten and crack something ( I was using a small faceless XT25 which I think would be easier to break than the one you are using.)

3) The 4M bolts from Lowe's weren't quite long enough so I countersunk the holes in the back plate with a forstner bit enough for them to work.

hifiside

Cool. I’m interested in measurements. I might have to get the square ones to measure.

Dirk

Same. It's always interesting to see how a given tweeter deals with the throat null.

DrewsBrews

Oah dang! and here I assumed you just glued the thing in place. lol. I like the idea of sticking the foam to the waveguide. Probably can just run the blade around the inside of the throat opening to cut it out that way. Easier and more precise to the actual throat shape.

Initially I wanted to try the beastmodes with these waveguides. Craig made me some adapters. Though I heard there are some response issues with beastmodes with this waveguide. I suspect it is either due to the large surround on that dome or the fact that the adapter plate adds even more depth to the throat. So I've been saving the adapters to maybe try with the standard xt25 or beast nipple Since that was what those adapters were designed for.

I want to try the rectangle Visaton waveguide some time too. Would be awesome to top a cabinet along with a 6.5". Looks like it is probably an identical waveguide profile, so what works with the 148 should work with the 150x220.

jr@mac

I would not personally use the Beast Mode with that waveguide, but I did use Beast Mode Nipple in it and was very happy with the results. Depending on where you cross it may require a notch to really flatten things out but I crossed around 1800 with a single 2.7uF cap and a single series resistor.

DrewsBrews

45mm m4 screws were the longest they had at Menards. With a 1/2" backer plate It was just long enough to get the flange bending slightly and sneak a slim jam nut on a few threads. I put a wood screw in the center to index into the dimple on the tweeter back plate. Though, I have my doubts if it would help all that much to prevent shifting in a drop situation. Maybe keep it from shifting so much it destroys the diaphragm.

Now I really do need a measurement turntable. Doh

DrewsBrews

This was the idea. I wasn't sure just how low I'd be able to stretch the 1204 down to to get away from the MAC-06 breakup. I thought maybe the WG could help, but probably just creating more headaches for myself and would likely need to tank the woofer peak anyway. Putting the WG on it was fun and pretty simple to try, whatever the outcome.