Monkey Coffin Build: The Vintages

[hongrn]

I finally finished my third and last project as member of the 2016 Speaker Design Team. The complete write up can be found in the Project Gallery.

http://projectgallery.parts-express..../the-vintages/

[hongrn]

A few more measurements that didn't make it in the Gallery: FR with grill versus no grill, vertical off-axis, and distortion:

[Wolf]

Very nice, Hong! Did you have to truncate the face on the midrange?
Wolf

[Kevin K.]

They look great Hong! I noticed your grill is being held by magnets. I only see four, are they really that strong?

Wish there was a way for all of the Design team projects to be at MWAF. I think it would be interesting for PE to commit a few hours to you guys on a Friday evening or Sunday morning. Kind of a show and tell so to speak. Do you ever attend?

[Millstonemike]

Love the look ...

And a couple questions.

Are the front edges of the enclosure sides/top/bottom veneered or is that natural wood?

I read the write up. You state the box is tuned to 28Hz with an F3 of 30hz. But the sim in the write up shows an f3 circa 50+hz. What am I reading wrong?

[JimHRB]

The wrong driver is listed in the Project Gallery writeup parts list for the woofer. Shows a 4.5 inch GRS full-range!

[hongrn]

Very nice, Hong! Did you have to truncate the face on the midrange?
Wolf

Indeed Ben. I just used a Dremel wheel to cut the top of the faceplate above the screw holes. Thanks.

[hongrn]

They look great Hong! I noticed your grill is being held by magnets. I only see four, are they really that strong?

Wish there was a way for all of the Design team projects to be at MWAF. I think it would be interesting for PE to commit a few hours to you guys on a Friday evening or Sunday morning. Kind of a show and tell so to speak. Do you ever attend?

The magnets are very strong compared to the regular ferrite ones. They're very hard to manipulate because of this, especially near the huge woofer magnet. I'm on the West coast, so MWAF is out of the question because of my current work load. It's good that I'm busy at work and make a living, it's bad that I'm busy at work... I was supposed to finish this project around September, but life got in the way. Thanks Kevin.

[hongrn]

The wrong driver is listed in the Project Gallery writeup parts list for the woofer. Shows a 4.5 inch GRS full-range!

Jim, Thanks for catching the error on the BOM. I'll let Jill know.

[hongrn]

Love the look ...

And a couple questions.

Are the front edges of the enclosure sides/top/bottom veneered or is that natural wood?

I read the write up. You state the box is tuned to 28Hz with an F3 of 30hz. But the sim in the write up shows an f3 circa 50+hz. What am I reading wrong?

Mike, everything is veneered over MDF. The baffle is the only part that uses birch plywood. The F3 is determined from modeling the woofer in Bassbox. If you looked at the sim, what's below 200Hz is a combination of near field and far field manipulation in FRD Response Modeler, so the curve display may not be as accurate as I'd like it to be. Thanks.

[kbzx35]

Very nice Hong! Can't wait to hear these!

[hongrn]

Very nice Hong! Can't wait to hear these!

You missed the beer party with Beau and Jon last week...

[Navy Guy]

Interesting combo. What level was the distortion sweep taken at? Would it be possible to see some high output sweeps (like >= 90 dB at 1m equivalent)? I'd like to see how that tweeter holds up.

[jhollander]

Nice work Hong. I like the updated vintage look with the lighter wood color.

[badman]

cool design reminiscent of Infinity Kappa 6. You could fully stuff the cabs because it won't impact the overdamped alignment meaningfully and might buy you some benefit. I'd definitely want subs- I always want subs but these are definitely not deep bass monsters, I bet the midbass is really nice and clean though. The F3 is certainly not 30hz, neither modeled nor measured.

Nice, fun project!