Got the first build and test results on the acoustic coupled active radiator design. Short version: it kicks ***, doesn't bother to take names, and might well be measured in thrust rather than SPL.
Two: Vifa TC9FD-05-16 3-1/2" Full Range Driver 16 Ohm
Part Number: 299-223
Eight: Sony 5" Dynamic Bass mini-woofer @ 5.5 ohms
Part Number: 299-011
Wired in nominal impedance 5.3 ohms, 18 g wiring throughout.
Front side of GRS firing into sealed box, rear ported to bottom and out
the scoop seen. All Sony 5" and Vifa 3.5" are on the front of the
sealed box pumped by the GRS 10". Drivers set with gasket tape, box sealed
with DAP all weather sealant. Box is 5/8" OSB throughout except bass port scoop, flexible linoleum tile. Sealed acoustic coupling section is 36" x 12" x 3", all frontal drivers except Goldman piezo being driven from behind by the GRS.
Sources: Fender Frontman 65R (65W RMS mono guitar amp) and Audiosource AMP100 bridged mono amplifier, 150 W+. Separately and together.
The frontal dimension is 48" x 12 ", the bass port being the bottom 12" X 12". I've played through a lot of amp and repro system in the last 50 years. I have never, NEVER, heard so much wide band volume fired at me through such a small space before. Subwoofer? Not needed. It's in there. This thing wants to get up and dance with the low bass. Transients? Have you ever heard Joe Satriani's pick scraping his strings as he lays into Surfin' With The Alien? I never had before. The drums on Mannhiem Steamroller's Fresh Aire 4 "Toccata" had a real presence when I played it through a pair of Koss "Kossfires". Through this box, I could almost reach out and play them myself. The Audiosource amp kept going into thermal protection when pushing more than 75%. The speakers didn't care. I played along with Satch on 'Alien', with the Audiosource and Fender both cranking. I could see the front panel moving, but still everything came out crisp and clean.
The second tower is presently being populated with its drivers. I'll repeat my request, that anyone within travel distance who has the devices and instrumentation for some real hard number crunching, please let me know -- this design has all appearances of being a tactical nuclear full tilt boogie machine, but it needs the kind of data expected from real engineering to prove its point.
Got the first build and test results on the acoustic coupled active radiator design. Short version: it kicks ***, doesn't bother to take names, and might well be measured in thrust rather than SPL.
Two: Vifa TC9FD-05-16 3-1/2" Full Range Driver 16 Ohm
Part Number: 299-223
Eight: Sony 5" Dynamic Bass mini-woofer @ 5.5 ohms
Part Number: 299-011
Wired in nominal impedance 5.3 ohms, 18 g wiring throughout.
Front side of GRS firing into sealed box, rear ported to bottom and out
the scoop seen. All Sony 5" and Vifa 3.5" are on the front of the
sealed box pumped by the GRS 10". Drivers set with gasket tape, box sealed
with DAP all weather sealant. Box is 5/8" OSB throughout except bass port scoop, flexible linoleum tile. Sealed acoustic coupling section is 36" x 12" x 3", all frontal drivers except Goldman piezo being driven from behind by the GRS.
Sources: Fender Frontman 65R (65W RMS mono guitar amp) and Audiosource AMP100 bridged mono amplifier, 150 W+. Separately and together.
The frontal dimension is 48" x 12 ", the bass port being the bottom 12" X 12". I've played through a lot of amp and repro system in the last 50 years. I have never, NEVER, heard so much wide band volume fired at me through such a small space before. Subwoofer? Not needed. It's in there. This thing wants to get up and dance with the low bass. Transients? Have you ever heard Joe Satriani's pick scraping his strings as he lays into Surfin' With The Alien? I never had before. The drums on Mannhiem Steamroller's Fresh Aire 4 "Toccata" had a real presence when I played it through a pair of Koss "Kossfires". Through this box, I could almost reach out and play them myself. The Audiosource amp kept going into thermal protection when pushing more than 75%. The speakers didn't care. I played along with Satch on 'Alien', with the Audiosource and Fender both cranking. I could see the front panel moving, but still everything came out crisp and clean.
The second tower is presently being populated with its drivers. I'll repeat my request, that anyone within travel distance who has the devices and instrumentation for some real hard number crunching, please let me know -- this design has all appearances of being a tactical nuclear full tilt boogie machine, but it needs the kind of data expected from real engineering to prove its point.
Got a good laugh out of your description. Glad your lovin' them! Did you do any internal bracing for the enclosures? Since you used 5/8" OSB and you mentioned the front panel 'moving'...
If it sounds that good to you with one, waiti until you have the pair going. Less volume needed from each one will yield a little less distortion from having to overdrive one cab. Like hannibal says- " I love it when a plan comes together". Glad your DIY venture has panned out to your liking. Thats what its all about
Got a good laugh out of your description. Glad your lovin' them! Did you do any internal bracing for the enclosures? Since you used 5/8" OSB and you mentioned the front panel 'moving'...
If it sounds that good to you with one, waiti until you have the pair going. Less volume needed from each one will yield a little less distortion from having to overdrive one cab. Like hannibal says- " I love it when a plan comes together". Glad your DIY venture has panned out to your liking. Thats what its all about
C.O.: Actually, internal bracing was necessary -- too little wood left after hole cutting. I'd gone through and glued/screwed strips in between the mini woofers. Also before setting the front panel in I'd installed blocks for it to sit on and get adhered to rather than having to reply on through-the-side screws. Upon inspection the front panel is intact -- two of the mini woofers were trying to escape and protruded half an inch. Gasket tape is clearly not adequate for this high power stuff -- back to Liquid Nails and DAP sealant.
Forgotten until now: stand offs for the bottom. It had been sitting flat on concrete. I wonder how much was lost through the floor? Think I'll go find out.
Sounds good Doc. Report back when your finished getting the pair 'up to snuff'.
That will now require another box of truss head screws, another tube of Liquid Nails, a couple-three scrolling jig saw blades, and to finalize things, the second Audiosource AMP100, due for ordering on the first. In the mean time the extension cab for the Fender sort of fell together as a tall, skinny, in-line design. That I can finish by the 1st, then complete the PA. The Fender add-on's shape came about due to the problems with cutting many holes almost filling the OSB face. I found a piece of good but knotty pine, 60" x 9.25" x 3/4". OSB still seems fine for sides, but I'm having better luck with this piece, so I'm building around it. Oh, and a Texalium/epoxy scoop for the bass port. And it's going on top.
Frankenwoofer Tower
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Originally Posted by drmcclainphd
