[JoshK]

Hi guys,

I am interested if any of you have clever ideas, or seen any clever ideas for supporting a sectioned OB.  Here is what I am thinking.  I plan to do a three way OB speaker with 2 15" drivers per speaker in a seperate sub-baffle and a 10-12" mid and waveguide in their own seperate sub baffle. 

So far my plan is to support the 15"s with a perpendicular spine and somehow attach the upper baffle by attaching its spine to the lower baffle's spine.  Alternatively, I could imagine the spine of the upper baffle being supported directly from the base. 

There are a few reasons why I want to seperate the baffles.  The independence from vibration transfer is a big benefit but my main reason is more practical.  I want to be able to change out the mid and experiment with mids.  A removeable upper baffle among a few other measures will greatly facilitate this.
Last but not least, if I want to experiment with all horns from mid on up, I can use the woofers in combo with this by removing the upper baffle. 

So I am looking for input.  All creative ideas welcome.  I have probably seen a lot of the ideas floating on the web, but please feel free to point them out anyway.

Josh

[Bob in St. Louis]

Somebody (either here or on Decware??) did a two way baffle, kinda of a typical looking baffle, but then cut it in half at a "diagonal/horizontal angle" creating a "double trapezoidal" shaped baffle. Then attached long vertical rod to the lower baffle extending then upwards like football goal posts. The upper baffle slid up and down on those rods, supports by a heavy string like a mini-blind in a window. Kind of a cool idea, but I'm sure the diffraction guys would have a field day with all those exposed edges.

Either that or build modular baffles that use a loose fitting mortise and tenon kinda "peg" that can stack on each other (think LEGO'S).

Bob

[markC]

http://www.audiocircle.com/index.php?topic=40594.0

You mean this one?

[Bob in St. Louis]

You 'da man Mark. Yup! That's the one. 

[gooberdude]

I think Darrel Hawthorne might offer a set of baffles that meet your goal...Stackables maybe?   Bob would know more on these, i'm outta the loop.  i do know they consist of 2 identical baffles per side, one sits on top of the other.  quick & easy DIY, plus the interchangeability factor would be sweet. 


OB SUPPORT:   Try to isolate the 15's as you mount them to be able to simplify the baffle's(s) overall design.  The full-rangers too if they are of the cone/piston type (not horns, only cuz I have no experience).   


my 15" auggie's (Sterlings too) are bolted directly to a 3/4" Birch plywood plate that's 16.5" x 16.5"...another Hawthorne Audio design.  A thick 3/4" x 3/4" gasket, avail at Menards, is adhered to the perimeter of the mounting plate & keeps the mounting plate from ever touching the main baffle.  This serves as both a suspension and seals the driver up against the main baffle. The driver peeps out of the main baffle perfectly flush, looks cool.

The mounting plate has a 1/2" diam hole in each far corner, and the main baffle has T nuts mounted into the front of the main baffle that correspond to the holes in the plate.  1/4" bolts go in from the back, through the mounting plate first and then screw into the T nuts, which pull the front toward the back making the Birch sandwich rigid & secure.  there is absolutely no movement with the design, except of course from the woofers which are now un-impeded by other vibrations.

This method of mounting drivers also strengthens the main baffle, which has been weakened by 2 large 15" holes probably.   



I remember a few years ago when the OB bug was really gaining speed, and 1 common idea was that OB drivers exert little vibration due to the nature of the design.   Not true!   

[Bob in St. Louis]

Yes Matt, the Hawthorne "Stackables" are EXACTLY what I was thinking as well. 
I assume (safely I believe), that Darrel's "stackables" are precut with holes that specifically fit the Hawthorne drivers and may not necessarily fit other drivers (there's always a slight difference in overall diameter from one manufacturer to another). So there's probably not anything along these lines that a fellow could buy to (exactly) fit any 15" driver.
I'm afraid sometime I shill the daylights out of Hawthorne stuff and was trying to shy away from mentioning the "stackables" by name. 

Bob

[Mr Content]

Josh, is this baffle just for experimentation until you find the driver combo that you like. I have a system that seems to work very well, but it it is fror a finished baffle, but I have a few parts of the prototypes hanging around the workshop. I could over the next few days put them togther and take some shots to post.


Mr C

[Mr Content]

O Josh I forgot to ask what your wood working skills were like, I may be able to modify the system if you dont have skills or tools.


Mr C

[JoshK]

I intend for this to be a finished baffle. I'd love to see your idea.

[gooberdude]

i hate to schill as well, but we're dealing with such a niche area of this hobby.   
i only mentioned it for the DIY design purposes.   

Wouldn't it be cool to be able swap full-range drivers easily??      aa


the 1 thing i should've mentioned is the sonic change that occurs when an OB driver is bolted to wood, preferrably Birch (for cost, avail and sound) as compared to the funky string & hook design.

That design is innovative and pure genius, no doubt about that.  And i've never heard it of course, but it may not yield optimal performance as the resonances in the basket aren't damped by wood.   I don't have much experience with a wide range of drivers & i by no means intend to offend anyone with any design of driver.  just a general statement about mounting a driver so it's frame is damped properly. 

I think of darrel's mounts as sound boards, no different than any of the Mapleshade air dried platforms i use.