Construction issue.

[Insane]

Hi

I would like to call upon all the wise guys 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. (this one http://www.parts-express.com/pe/show...number=264-871)
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 :P)

[dlneubec]

I personally don't think that concept will work well at all. Rear firing might work for the very low end, say below 200hz or so, but above that you would have a plethora of problems to overcome.

I'm having a hard to visualizing where your speakers will be used, but how about an up and downfiring woofer, situated at the back of the encosure where it is larger, firing at each other with a tweeter positioned in between.

This would be sort of like the top end of my HOSS project, in the MTM section (see photo below). If you were to angle the baffles a little from horizontal, say +- 15º that might work up against the wall, if that is were you are placing them. There is a write up of it here if interested in more info: HOSS write up

[Moondog55]

I think you will find yoyr design constaints are going to mean expense, but this driver may suit.
i've not used Jordans but you may find it works well in you particular situation.
I do believe they are a very good unit, and should covet that range and above

http://diyaudioprojects.com/Drivers/JX92S/

Good luck

[Moondog55]

Sory that link is for the 5 inch. there should be a 2inch unit, I'll try again or just "Google" 2inch Jordan speakers

http://www.decibelhifi.com.au/prod341.htm