I have been reading a lot about and slowly falling in love with the open baffle concept. I bought an Executive BT kit last year but with a new baby never found the time to put it together.
I was thinking about repurposing the batteries + amp + CX120-8s combined with 1 GW-215/4 in some kind of origami briefcase setup to listen to outside. I want to keep it light and compact so it would kind of fold in on itself for storage but then open up relatively wide for some soundstage. I would store it indoors so weather issues are no problem I think. Has anyone done anything like this?
One specific question I have is with the baffle thickness for the sub. Obviously a thicker baffle would be ideal but they are heavy. Could I get away with say 3/8" plywood with reinforcements? What material would have the best combo of low weight and strength? I guess another question is whether it would be worth getting more efficient full range drivers to get more battery life. Just curious what other people's experiences have been.
I was thinking about repurposing the batteries + amp + CX120-8s combined with 1 GW-215/4 in some kind of origami briefcase setup to listen to outside. I want to keep it light and compact so it would kind of fold in on itself for storage but then open up relatively wide for some soundstage. I would store it indoors so weather issues are no problem I think. Has anyone done anything like this?
One specific question I have is with the baffle thickness for the sub. Obviously a thicker baffle would be ideal but they are heavy. Could I get away with say 3/8" plywood with reinforcements? What material would have the best combo of low weight and strength? I guess another question is whether it would be worth getting more efficient full range drivers to get more battery life. Just curious what other people's experiences have been.
I have dragged my open baffles out in the garden as party speakers and that worked well, but there was no room bass resonances. That is good or bad, depends on what you want. Noo BOOM! anyway. The measurements are 0.6 x 0.9 meters, drivers are two 15" Eminence Beta 15A each (in total 4) with Qts = 0,58. You need more area for a boom box (or Boom Baffle?) for outdoor use but as far as I have experienced the thickness or wheight is not particular significant. My is still a prototype/proof of concept, made of 12 mm/0.5" board with no reinforcements and still they really can imitate a kickdrum indoor.
Nearly a year later, I am still thinking about this project but with different drivers and concepts....
Thanks, this was very informative. The software is great too. Pretty much nailed the Quarter-Wave Eminence Alpha response. Kind of bumming me out though as the drivers and baffle sizes I'm looking at are not super efficient below 100 Hz. Even that good Quarter Wave design only hits about 85dB which is something I didn't realize. I will probably still mess with this project anyway...
I have about 32W for 2 drivers or 65W I can put in one driver. But I will be listening to this at low volumes and/or relatively near field, and it will be replacing a little Bluetooth speaker/"competing" with my PE Executive box. So demands are low, but I would like it to be able to run on batteries sometimes so efficiency matters too.
I'm considering this type of build as well. Can the lack of bass be compensated for with some bass boost and a driver with a lot of excursion? What about trying to dampen and prevent the backwave cancelation by covering the back side with heavy asphalt lined felt folded up like an air filter behind it, sortuva cross between a vented box and an open baffle? That's probably just crazy talk tho with a lot of misunderstanding/ignorance of the design issues.
Bass boost and excursion means bigger amplifiers and shorter run-times.
Honestly, I'd just go for a sealed/ported/passive-radiator enclosure and call it good.
Chris
