Is there interest in a large three way "monkey coffin" collaboration?

[rpb]

Re: Is there interest in a large three way "monkey coffin" collaboration?

rpb, by "rigid fiberglass" ; are you using the fiberglass ceiling tiles, or something else?
thanks,
nikkoluvr

A friend gave me a box of ceiling tiles. That's what I use. I peel off the facing. The fiberglass is about 1" thick.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Thanks Kim and Chuck,

I have always understood that if anything you want a sealed chamber for the mid to be Q of .7 or lower so that sounds like what you guys are recommending.

Also, call me as fickle as a pickle but since it seems like we are favoring the Faital mid then I am going to say it just makes better sense to use the Vifa tweeter. It will make it all PE and will definitely get the job done. The SB tweeter may be more highly praised for it's distortion performance but I think it would be nice to have the build be all PE. I don't really see a huge benefit in using the SB just to make it different than RIOS. I guess that leaves us back where we were about 10 pages of posts ago:rolleyes:

+1

[rpb]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Thanks Kim and Chuck,

I have always understood that if anything you want a sealed chamber for the mid to be Q of .7 or lower so that sounds like what you guys are recommending.

Also, call me as fickle as a pickle but since it seems like we are favoring the Faital mid then I am going to say it just makes better sense to use the Vifa tweeter. It will make it all PE and will definitely get the job done. The SB tweeter may be more highly praised for it's distortion performance but I think it would be nice to have the build be all PE. I don't really see a huge benefit in using the SB just to make it different than RIOS. I guess that leaves us back where we were about 10 pages of posts ago:rolleyes:

I generally don't think much about the Q. If I have a speaker with lots of room in the box, I might use .75 cu-ft just for the mid with about 2" fiberglass lining all walls. Usually though, I have to compromise a little to keep the speaker size reasonable, and use about .4 cu-ft. I would consider .2 cu-ft an absolute minimum. Mostly because I want the 1" lining, but I also want a little room between the mid cutout, and the fiberglass.

[isaeagle4031]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I did just that Kim. My mid sits in a .5 cube enclosure, lined with 1.5" open cell foam and a few wads of a bamboo/poly blend. I will also add that I angled the rear panel back as well. I didn't worry about the q at all.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I was only saying that a high Q tiny enclosure for a mid could give a hump in its response, possibly in the region of crossover to woofer. I have no idea the volume of the enclosure behind my mids but I know it is more than large enough. Lined with 2" OC703 on all walls....

I did just that Kim. My mid sits in a .5 cube enclosure, lined with 1.5" open cell foam and a few wads of a bamboo/poly blend. I will also add that I angled the rear panel back as well. I didn't worry about the q at all.

[thekorvers]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Also, call me as fickle as a pickle but since it seems like we are favoring the Faital mid then I am going to say it just makes better sense to use the Vifa tweeter. It will make it all PE and will definitely get the job done. The SB tweeter may be more highly praised for it's distortion performance but I think it would be nice to have the build be all PE. I don't really see a huge benefit in using the SB just to make it different than RIOS. I guess that leaves us back where we were about 10 pages of posts ago:rolleyes:

Good idea! If there is enough interest in this design, we may be able to have PE put some kind of components kit together with a price break.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Parts have been ordered!

http://www.parts-express.com/dayton-...oofer--295-120
http://www.parts-express.com/faitalp...-ohm--294-1150
http://www.parts-express.com/vifa-dx...eter--264-1020

Once I start doing some construction and get in box measurements I will start a new build thread to document it.

Quick question on the mid; what would be preferred?
1. Rearmounted with a roundover
2. Surface mounted
3. PITA flushmounted octagonal frame

[djg]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Great news. I would mount the hexagonal mid by just routing a circular rebate with a Jasper jig and filling the little scallop pieces in with black painted wooden pieces, to give the visual of a round driver. I find that hex shape unattractive, especially with two other round drivers.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I agree the hex shape and stamped frame would be unattractive. That is why I was thinking of rearmounting with a roundover. Your method would work too but I"m not sure it's less work than coming up with a template to properly flush mount it. It would give more of the appearance of a round driver though.

Are there significant acoustic problems with rearmounting and putting a nice roundover or chamfer on the front of the baffle?

Great news. I would mount the hexagonal mid by just routing a circular rebate with a Jasper jig and filling the little scallop pieces in with black painted wooden pieces, to give the visual of a round driver. I find that hex shape unattractive, especially with two other round drivers.

[djg]

Re: Is there interest in a large three way "monkey coffin" collaboration?

My idea would be very simple to execute. Cut a circle the correct size with a jasper jig and cut correct sized sections off the perimeter, 20 minutes tops. As far as rear mount, someone that knows about speaker design should answer that. I am a builder, not a designer.

[rpb]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I agree the hex shape and stamped frame would be unattractive. That is why I was thinking of rearmounting with a roundover. Your method would work too but I"m not sure it's less work than coming up with a template to properly flush mount it. It would give more of the appearance of a round driver though.

Are there significant acoustic problems with rearmounting and putting a nice roundover or chamfer on the front of the baffle?

Don't rear mount it. If you do, the alignment with the tweeter will be way off.

[Jay1]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I would just surface mount the mid with an overlap on top of the tweeter faceplate.

Edit: The mid is a good choice based on the design and budget. If you keep the build difficulty low more people may build it. Having to flush mount this driver will instantly scare off noobs, even though it's as simple as routing a 5.75" hole with 7.15" recess and filling the hexagon areas with bondo.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

That could be pretty slick.

My idea would be very simple to execute. Cut a circle the correct size with a jasper jig and cut correct sized sections off the perimeter, 20 minutes tops. As far as rear mount, someone that knows about speaker design should answer that. I am a builder, not a designer.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I think you are definitely right on that any added difficulty of the build would scare some folks off. Do you think an 8mm thick driver frame will have too many diffraction effects?

I mean if surface mounting would not cause strong enough diffraction problems to require treatment in the crossover then the builder could build it either flush mounted or surface mounted. Changing the z offset 8mm can't be that huge of an issue I wouldn't think. But what do I know.

I would just surface mount the mid with an overlap on top of the tweeter faceplate.

Edit: The mid is a good choice based on the design and budget. If you keep the build difficulty low more people may build it. Having to flush mount this driver will instantly scare off noobs, even though it's as simple as routing a 5.75" hole with 7.15" recess and filling the hexagon areas with bondo.

[djg]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Both the mid and woofer here have the unsightly black cardboard gasket showing on the front surround. Even flush mounted, their look is unfinished. Maybe a grill detailed in the design would help. My lost JBL L100T with grill looks nice to me.