Fast, fun, Inexpensive OB project

One of the nice things about the Original Manzanita and Manzanita Ultra is both designs are fairly forgiving. As Pano mentioned, you do need to pay attention to wing depth. As long as you do not exceed 4" depth (from rear of baffle) you are OK. A slight taper of thicker at the bottom and thinner at the top is good. Say 4" down to 2" or so on either design seems to work OK. The shallow asymmetrical cavity created will be more or less resonance free while decreasing the F = and adding structural strength.
 
Thanks for chiming in John.
I was thinking of making the wings tapered toward the ends anyhow, so I can accomodate the trapezoid shape of the grundigs without creating a resonant space.
I guess making the top and bottom plate assymetric is as important as the sides.

I'll be sure to document everything Pano :D
It's going to be made from solid oak strips, as I suddenly have a lot of them on hand.
 
One of the nice things about the Original Manzanita and Manzanita Ultra is both designs are fairly forgiving. As Pano mentioned, you do need to pay attention to wing depth. As long as you do not exceed 4" depth (from rear of baffle) you are OK. A slight taper of thicker at the bottom and thinner at the top is good. Say 4" down to 2" or so on either design seems to work OK. The shallow asymmetrical cavity created will be more or less resonance free while decreasing the F = and adding structural strength.

There are some OB designs by Danny Richie at GR Research that have asymmetrical wings where on side is much longer than the other. It appears to be about 2 feet long versus about 4" on the other side. Any comment about this type of configuration?
 
Not familiar with the particular GR Research model you are asking about. From a first glance perspective it does not seem to make sense. However, Danny has designed it that way for a reason. Without having a complete understanding of the design I can not comment further. J

John. It's called the NX-Otica MTM Monitor. Not yet on the GR Research website, but people are building it. Here is a link with some very good pictures:

Uilleam Audio | Lone Star Audio Fest 2019 | Part-Time Audiophile

You can see that the inside wing is much longer than the outside wing. It looks to be about 2 feet overall and also has some deadening material on it.

I'm sure Danny has an explanation somewhere, but I haven't seen it yet. Curious what you think about the very long wing. It's quite different from most designs that use smaller wings.
 
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A short baffle on one side and a long one on the other is something I’ve been intrigued by.

As has been discussed above, one doesn’t want a pair of side panels to be too long as they create a resonant box. It seems to me that a single long side would extend the bass significantly while not creating any ways near as much resonance as 2 long sides. Sure, the bass would probably be determined by an average of the 2 side lengths, but would be significantly lower than 2 4” sides.Right?
 
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Just to be clear When I said “it would be significantly lower than 2 4” sides”
I meant “it would be significantly lower FREQUENCY than two 4” sides”
Which you understood but I don’t want to confuse others.

I hadn’t thought about the directivity, but at lower frequencies maybe not so much, as they start to become omnidirectional?

If so, then perhaps that’s not invalidating, it perhaps could be used to “steer“ the bass towards the listener The way Nelson Pass’ slot loaded woofers are understood to do. As mentioned, more data required.

Siegfried Linkwitz probably wouldn’t approve!
 
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Never tell on yourself, John.


On the other hand..



How about more details re:the Manzanita Being Extra ?


I already had the 123s in another project, and a pair of 18s at 50$ea restocked proved too hard to resist; I could work on the baffles even if the crossover isn't ready yet......