Speaker construction problem

[Insane]

Hi

I would like to call upon all the wise men in this forum. To help me solve something i think will be a construction problem. I`m currently designing a loudspeaker, That has a width problem in the front. It is only 100 mm wide ( 4"). The width is a design must and can not be changed. facing backwards i have a little more space. Here i will fit two 5,5 or 6,5" woofers, in a vented cabinett. With the vent holes facing forwards.
In the front i will mount a ribbon type tweeter.
So the bass range and the tweeter range is covered.
>400 and <2000 hz are covered exelently. now here comes the pickle. The front can`t fit anything bigger than a total of 75 mm in width. Meaning a 4" or a 3" cone type mid range is out of the question. So the problem here is how do i cover the mid range with good quality

I have been fiddling with the idea of using the woofer drives as bass/midrange drivers. (the ones facing backwards) But i`m quite concerned about frequency distortion if i do so. And since this is supposed to be a quite hi end speaker we can not have that.

Now, i was thinking i could add a second ribbon drive in the front. The advantage i see by using ribbon drives is that they are quite narrow in size. Usualy less than 80mm (not counting the mounting plate). And i have seen them, all the way down to around 1000 hz with a minimum of fq disortion.

So here are the questions:

1. Can i use the woofers facing backwards as midrange, without any significant distortion.

2. How high in the fq range can backward facing speakers go. Before we measure significant distortion.

3. Are there any ribbon drives ranging from around 300 to 2000 hz.

4. Any other suggestions for drives ranging from 300 to 2000 hz with good quality.

Thanks prehand for any help.

Vik

(apologies for the language )

 

[jliedeka]

You seem to be locked into a pretty tricky design. Are you using someone else's crossover that you have to stick to a certain baffle size?

I guess what I'm really asking is why in god's name are you trying to shoehorn speakers into a 4 inch baffle?

If it's someone else's design, aren't there any construction notes? There are certainly more workable designs to be found at places like htguide.com and ZaphAudio.

For the record, Infinity uses some membrane drivers in one of their lines. You may be able to find similar drivers but they probably won't be cheap. You could then side mount a cone woofer.

Jim