Site Links
Howdy, Stranger!
It looks like you're new here. If you want to get involved, click one of these buttons!
Quick Links
Categories
In this Discussion
Who's Online (7)
- DrewsBrews 5:18PM
- Ed_Perkins 5:18PM
- justinlee101 5:18PM
- kenrhodes 5:18PM
- rjj45 5:18PM
- Tom_S 5:18PM
- traw 5:18PM
1.5 way sealed bass, top box interchangeable
Finally, finally making sawdust.
Going back to a two stacked box build where I can change out the top (broad ranger, coaxial, or mid / tw separates).
I’m now ‘sold’ on sealed woofer(s) so going with a pair of 8in sealed 1.5 way set-up with the .5 rearward facing. Easy enough to incorporate via active, with interchangeable passive top(s).
Top box; while I recently built an ~open back/side Celestion coax, I’m starting with my old friend- an Audio Nirvana Super 6.5. It’s a very solid, cast aluminum framed, broad ranger with excellent extension. So keeping it ‘simple stupid’.
I may down the road try a Markaudio / super tweeter combo (beyma slot or fostex super tweeter) as this image is ‘calling’ me.
Comments
What is "this" image.
On the other hand are you doing any timing difference for the rear 0.5? Interested to see the results. Would there be any cardioid benefits?
Didn't see a description (just the image). Looks like a fostex FE168EZ, not certain of the ribbon (could be a fountek?), possibly a 12in W.
Re the 1.5 woofer box, I'll definitely post when I get there. I'm just thinking potential benefit of offsetting forces front-to-back in a bipole configuration, and the .5 being a 4pi radiation pattern in its frequency range, so location indifferent. Not looking to do a cardioid as they will be played as bipoles, however interesting though if ran as dipole one could play with the .5 level, as well as delay.
Woofer is a SS paper Revelator, and tweeter is a Fountek Neo CD1.0. Size comparison looks like the Fostex is a 4 or 5".
InDIYana Event Website
https://www.fostex.jp/en/products/fe168eσ/
Luckily you're not going to use that Fostex driver as a full range! I wouldn't even publish that frequency response if I was Fostex. Note the 10 dB/div scale
Pretty sure it's this one...
https://www.fostex.jp/en/products/fe108eσ/
InDIYana Event Website
Thanks, I didn't know they had made a 108 version.
The fe168 is out of production (and yes it would take a few notch filters to straighten it out, if then). I just thought it was an interesting cone design (and didn't know they made a fe108- thx Ben). I'll be using my AudioNirvana's for starters. But in any event the Markaudio's look to be better broad rangers then the fostex, at least vs the fe168
There was a 208 as well.
InDIYana Event Website
I’ve got the top vented boxes put together (not yet felted / foam lined). Tuning with vent open ~ 180ish, with a bit of foam ~ 120ish, which should work out just fine as I’m at this juncture targeting 1st O HP in the neighborhood of 180-240Hz.
I’m going with a black stain / flat topcoat for the bass unit (Baltic birch) which, per a couple of test pieces, lets the wood grain show through a bit through the black.
I’m looking to stain the top boxes white (with a flat topcoat). Gave it a go and found that white stain doesn’t really do much of anything to the Baltic birch.
So, I’m thinking maybe I need to mix some white stain or paint directly into the flat topcoat to move this towards white? I want the grain (what there is) to show through similar to the bass unit (so not wanting to just paint white).
Suggestions from you guys with painting / staining experience would be appreciated.
If you want white with some woodgrain peeking through, a white wash would do it. That is what I did on my TV stand. I did a roughly 50:50 mix of white primer to water ratio. Brushed on one coat. If you want less white and more grain, you can use more water/less primer. And/or you can also wipe off excess to reduce the white, like you would stain. But I bet you gotta work quick to do that since it dries quickly. Then finish up with water based polyurethane to seal it without turning the white yellow.
https://diy.midwestaudio.club/discussion/2435/tv-stand/p3
Who said water (based) and oil don’t mix?
I finished up the broad-range box; lined, and lightly stuffed the vent (tuned to ~the driver's free air Fs, which will actually be below final Xover frequency with woofers). I'll be placing some white felt in the corners of the baffle.
Mostly done making sawdust, all pieces cut. I'll just need to trim the top of the woofer box as I flush mounted the binding post (for the broad-range which will sit on top). Instead of making a big form for a router, I found it easer to cut the small square out of a ⅛ inch sheet of BB ply and glue it to the top board. I'll just need to flush trim it. And set-in for the speakON 4pole.
