> Sorry. I might have mixed tweaks from two constructions. The drawing
> is to scale, the text measurements might not have been updated since
> the last tweaks. I'll see if I can track the exact measurements
> down. An 1/8" change in the opening or width measurements of the
> top/bottom changes the boundary face angle considerably. Aiming for
> the 35 degree corners first is a good way to go (180 - 110 =3D 70/2 =3D
> 35). Another important dimension I'd try to hit is the capsule
> set-back distance. Mic capsule center to center spacing can be from
> 6-9". We are experimenting with almost all of them though.
>
> If you used 2-45 degree angles, the faces should be angled at 90
> degrees which will make for less center imaging. If you get too big
> of a hole in the middle (particularly in high frequencies), the 90
> degree angle is a probable source. Also, narrowing the foam baffle
> in the center would probably help some. The 10mm capsules will help
> off set this as they have better high frequency response to bring out
> more treble in the center of the stereo field compared to larger
> diameter flush-mounted mics like AT4022's. Who knows, you may like
> your mistake better than Crown specs-- a perk of experimentation.
>
>
Hmm, OK. Well, it's a first build so I can't complain about it. And as
stated, experimentation is fun.
I'll print the drawing to scale and go from that next time. Should make
things easier.
Fabric/open cell foam typically won't block under ~1500Hz. Optimally,
> use something denser like leather gloves if clothing is the preferred
> theme. The mice will chew up the foam baffle first and then the
> gloves. :-)
>
HAH! Has anyone filled it with foam and then closed up the back?
I did a quick recording earlier and the socks didn't block "squat" from the
rear. Surprised the hell out of me. Definitely going to have to fill it up
in the back!
And a number of other key folks who are following- up on the
> invention, fine-tuning the principles for diffuse field recording.
> If you want to join-in on the conversation, we have an email
> listserve now that is in the "Links" section of the blog:
> http://diystereoboundarymics.blogspot.com/ Rob D.
>
Heh, OK. Will be pretty much silent there but I can always read and learn
more!
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