Fast, fun, Inexpensive OB project

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You'll need more attenuation on the Faital for sure because it is about 6dB louder than the Vifa - so a higher value resistor is needed. I'd start with the same 6uF high pass but would expect to go smaller. You might add a resistor to make an L-Pad to keep the impedance the same. Also leave the trap to tame the top end and adjust its values to suite your room and ears.
 
So the distance between the drivers and the end of the wings is not an important parameter? I mean if I do take a considerable chunck of the edges of the front it wont mean anything?
I'm looking into morphing the Ultras into something a little like this:
fe742a267b2ae7dc5137149e884d7bf8.jpg
 
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Funny! I actually owned a pair of those Grundig speakers. They made passive and active versions with valves. I had the passive version, and they were surprisingly small.

Looked cool, sounded like crap. Nothing I could do ever made them sound better.

Still a pretty design. "Maybe" scaled up and with decent drivers it could sound good. But it would not be a Manzanita, Ultra or otherwise.
 
Do you plan to do a ported box like the Grundig?

No of course not, that would make it something completely different, and not suitable for discussion in this thread. When I say I want to make it look like the old Grundigs, it does not mean I want in any way to mimic their mode of function, just grab design details that makes my version of the manzanitas look more like a piece of furniture than something cobbled together in the garage.

I can change the side edges, and make top and bottom look somewhat the same from the front. The back "box" will be nothing but a fabric covered emptiness. I would like input on what parameters not to fiddle too much with, hence my question of wing+baffle size.
 
Yes I would hope so. My question was just what parameters I should be wary of changing.
The top hat and bottom will introduce some problems, but I can at least optimize the back of them. The left and right edge of the baffle will be rounded quite a bit, and the wings will probably be made very thick so that I can make the outer triangular form of the raumklangs without compromising the original design.
 
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Well to start the baffle proportions are different, so that will change things. The bottom plate won't change much from the Manzie design, but the top plate will. Rounded baffle and wings will be fine, just don't go too deep or you'll get cavity resonances.

Try to stay close to the Ultra dimensions or you'll end up with a lot of crossover work.
 
I will keep the proportions the same as the Ultra, but the baffle sides will be curved. The question is then whether I should lenghten the wings to compensate for the shorter distance.

The top plate I will change to, just keep the front look, but the backward side could be designed differently. Again knowing what to go for or avoid would help.
 
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I don't think the curved side will make much difference to the overall acoustic path. But if you can calculate the difference and make up for it, do it. :up:

Making the wings tapered is a good idea, at least on one side. Perhaps you can imitate the Grundig deign there as well.
 
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