Baffle Thickness

[snmhanson]

Hello all. Been a while since I posted here as I haven't had any builds lately. I finally got back into the groove and am currently working on a pair of Zaph ZRT sealed bookshelves. I've got the boxes built and hope to veneer this weekend. For the baffle I am thinking about using some Paperstone countertop material I've got laying around. This is a very dense synthetic material made out of recycled paper product and resin. Somewhere between a granite countertop and a very dense hardwood. I've got two pieces of it that just happen to be about the perfect size, except they are only 1/2" thick. Can anyone tell me how having only 1/2" thick baffles might impact the sonics? I am not really concerned about durability of the material or the baffles flexing, just if losing 1/4" will make a difference. I suppose I could add a 1/4" false baffle to the speakers and/or laminate a piece of 1/4" MDF to the Paperstone, but I 'd rather not do either of those if I don't have to. I will probably make the baffle removeable and easy to replace regardless, though it would still be nice to know up front if I am going to face any issues with the sound. Any advice or insight?

Thank-you!

[technodanvan]

Got a couple questions for you. How are you going to mount the drivers to the baffle? Surface mount, or some sort of rabbet/rebate involved? Does the Paperstone lend itself to wood screws, or maybe hurricane nuts or something?

You also mentioned the baffle will be removeable, how are you going to do that? Will it involve attaching the baffle to bracing at all?

[snmhanson]

For mounting the drivers wood screws should work as long as I drill the pilot hole to the correct diameter. I'll have to double check Zaph's website as to whether they are surface mounted or not. I presume at least the mid-drivers will be flush mounted. Even if I am only left with 1/4" thickness for the speaker mounting screw it should be enough to support the drivers and not break out. I've worked with that material before and it is pretty robust.

To make the baffle removable I will mount braces in the corners of the boxes - and maybe mid-way down the edge. Then use T-nuts and bolts to be able to attach and remove. I'll also use some sort of gasket to ensure it the speaker is airtight. I have a pair of Statement Monitors that I built quite a while ago and used that method to mount the baffles and they are still going strong after 12+ years - though right now I have them taken apart to re-veneer.

[technodanvan]

Personally, based on your description of the substance, I think it would be alright - especially if you had a connection midway down the edge. Since they're removable you could always try it out and compare it to a traditional 3/4" baffle if you were really worried about it. Should be really nice speakers.

[JonMarsh]

Synthetics composites can be very useful - I use some of the thicker Leecraft phenolics (1/2") in some recent experiments (which is how the material you describe would probably be classified) and these kinds of materials enable pushing the panel resonance way up in frequency, which is usually a good thing, as it may not be significantly excited by the woofer frequency range.

I also like the 1/2" Leecraft for building crossover boards, as it is plenty strong enough to handle the largest inductors you might consider.