Hmmm? It would only be for the bass bins which would be crossed at somewhere around 500 Hz. So the roundovers would be more for looks than for diffraction performance.
NBL veneer can do a 3/4" radius according to Tape Ease. From their website. " The NBLhas the backer wood-grain the same direction as on the face, giving
you the option of doing as little as a 3/4" radius going with the
wood-grain.These materials are
a hair less then 1/16" thick
for 2ply and NBL."
I ordered three large sheets of paper backed makore crotch veneer. Hopefully I can get a single piece to wrap around the front (with 3/4" round overs) and cover both sides without cracking. Where should I order veneer softener from? And what is wrong with using contact cement besides the insanely bad fumes? It was very easy to apply and has held up well for several years, and the headache went away the next day LOL
I ordered three large sheets of paper backed makore crotch veneer. Hopefully I can get a single piece to wrap around the front (with 3/4" round overs) and cover both sides without cracking. Where should I order veneer softener from? And what is wrong with using contact cement besides the insanely bad fumes? It was very easy to apply and has held up well for several years, and the headache went away the next day LOL
Nothing is wrong with contact cement if the fumes are ok in your environment. My workshop is in the basement, and I need non-toxic solutions.
I ordered three large sheets of paper backed makore crotch veneer. Hopefully I can get a single piece to wrap around the front (with 3/4" round overs) and cover both sides without cracking. Where should I order veneer softener from? And what is wrong with using contact cement besides the insanely bad fumes? It was very easy to apply and has held up well for several years, and the headache went away the next day LOL
Nothing is wrong with contact cement if the fumes are ok in your environment. My workshop is in the basement, and I need non-toxic solutions.
On another note: I just tried Andrew Jone's recommendation on how to measure the woofer's FR below 200 Hz... OmniMic hanging inside the enclosure. I must have had the mic end way too close to the internal end of the port because my measurement was a large peak right at 32 Hz (the port's tuning frequency), falling off quickly -15 dB at 200 Hz, then a huge nose dive above that.
On another note: I just tried Andrew Jone's recommendation on how to measure the woofer's FR below 200 Hz... OmniMic hanging inside the enclosure. I must have had the mic end way too close to the internal end of the port because my measurement was a large peak right at 32 Hz (the port's tuning frequency), falling off quickly -15 dB at 200 Hz, then a huge nose dive above that.
It would be very interesting to compare that with close miked woofer and port measurements.
But Chahly - Stahkist don't want speakers that look good, Stahkist wants speakers that sound good!
I do plan to try some more internal measurements as it makes total sense to me. Next time I will duct tape the mic facing upwards and away from the port and the rear of the woofer and see what the results are. End of the day I have had very good results measuring the woofer and the port, both near field (external), then SPL correcting the port measurement, then blending them together.
I seem to recall that Andrew's measurement technique involved some Calculus (integral or derivative, can't remember which) being applied to the raw measurement. I would have really liked a demo or a brief write-up.
From my notes, Andrew shared two techniques one with the microphone in the box, the other was calculating an equivalent impedance circuit then doing some double differential calculation to create a derived woofer FR curve. He kind of glossed over the math part, which would have been interesting to see.
Yes that is what I recall too John. I wasn't overly interested in his derivation of bass response from the impedance plot. I was, however, very interested in his "mic in box" method. I don't remember him saying the direction of the mic was all that important, more so that the mic was kind of in the middle of the box, not laying on one of the internal panels. I'll give it another shot and see if things change significantly.
Exactly, centered between the port and woofer, maybe? If it's a test enclosure I'd try multiple locations and see what kind of changes are seen to see if it matters where the best reading comes from.
Well I gave it two more attempts with the mic in very different orientations. Almost exactly the same outcome in all three mic positions. As a sanity check I ran a near field FR on the woofer (1/4" from dust cap). The woofer, port, and enclosure are functioning exactly as predicted by the measured T/S parameters with Unibox. Maybe AJ was giving us a zinger
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InDIYana Event Website
My workshop is in the basement, and I need non-toxic solutions.
Veneer softener: http://www.rockler.com/veneer-glycerine
Mix glycerine with alcohol and water.
Real Good Article: https://www.joewoodworker.com/veneering/flattening.htm
Almost all the letters have fallen off.
InDIYana Event Website
From my notes, Andrew shared two techniques one with the microphone in the box, the other was calculating an equivalent impedance circuit then doing some double differential calculation to create a derived woofer FR curve. He kind of glossed over the math part, which would have been interesting to see.