Replacement full range driver for Koss M80 speaker?

[drabina]

I have a pair of Koss M80 Plus speakers with woofers that have bad surrounds. I would like to use one for a DIY sound bar type speaker for my racing simulator. The plan is to remove the tweeter, replace it with a volume control and to replace the two woofers with a full-range drivers for left and right channel. Any ideas what drivers would fit and I could use for this project? I believe the current woofers are 4".

[jhollander]

What's the internal volume and driver cut out size?

[philthien]

If you decide to repair:

https://www.ebay.com/itm/4-rubber-su...GIDz:rk:8:pf:0

Those little Koss speakers really weren't bad at all. If they're otherwise in good shape, I might consider fixing them and adjusting your plans on how you'll use them (maybe get a little amp and run them stereo).

[drabina]

Sorry for a late reply. I did not get notifications about the replies.

The volume of the enclosure is 183 cubic inches. The inside measurements are 11.5 x 3.75 x 4.25. The diameter of the cutout is 4".

Here is a photo of the enclosure. My question should actually be what would be an inexpensive full range driver to put in the enclosure (two of them) to change this speaker from MTM to sort of stereo sound bar in one box. The middle spot where the tweeter was will have a plastic panel with on/off switch and volume pot. Inside I will have a small 20W class-D amp (TA2024).

I am not interested in fixing the speakers. At $20 per driver, it would be too costly and I already have enough speakers.

[Chris Roemer]

Couple things:
If you want 2 (stereo) speakers in there, you should really divide the sides, internally.
Not too many 4" (full range) drivers that would have acceptable top ends (RS maybe, maybe paper RS?).
Not too many 4" that'll go very low (probably have to add ports?) in 0.05cf per side.

Something like the ND65s would probably go to 60Hz w/each side separate, and ported (or ND91s maybe).
To use smaller drivers you could plug the large hole and re-cut for something smaller.

What kind of freq. resp. range were you hoping for?

[drabina]

I understand that with the small volume and 4" driver I will not have a good speaker. I am building this speaker for my racing simulator so the sound quality or frequency range is not too important as long as I can hear the engine sounds. :-) I think I should be able to divide the speaker into two internal boxes but again, it is all about functionality not the quality of sound. Also, I would like to keep it sealed as I am trying to get this setup without too many modifications. I still have to pull 12V from my PC, add power switch, audio signal input jack and add the volume pot. This is all going to add mess of wires in this small box.

[Jake]

Sounds like you want to keep the box stock and just have something that functions. If that's the case, you could use the pc105-4 with the box heavily stuffed and a large bipolar capacitor inline with the positive lead to cut off the lows.

[drabina]

Thanks. Any idea what size of the capacitor should I use?

[Chris Roemer]

A 200uF series cap and 2.0mH shunt coil (2nd order) should protect them up to about 20w RMS.
A cap alone won't do much because of the impedance spike near 160Hz from the closed box.

[jhollander]

I did a sim on another site for the DA115

[Billet]

The DA115 would be a good choice, it is a nice sounding driver with a fairly wide range.

[drabina]

So which would be better? PC105-4 or DA115? I guess 4 Ohm version would be preferred for the TA2024 but otherwise, cheaper is better for me.

[Chris Roemer]

Probably either one would be okay in YOUR situation. PC is cheaper, DA has slightly more Xmax. PC is about 5dB more sensitive. Choices, choices, choices . . .

[drabina]

I will go with the PC-105-4 then since it is 4 Ohm which may be better for the low powered TA2024 amp I have. Thanks again to all who replied.