Full range and/or High Efficiency possible in small cabinet?

[Seraph]

Quite a few years ago I rescued three (3) surprisingly well built small cabinet off the curb. They had some very minor blemishes but what an injustice to just abandon them. Unabashedly I confess that to date, I have not done anything with these. I have been contemplating full range higher efficiency for low powered amps but am yet to settle on an enclosure. In the mean time I was wondering if I might be able to fit some decent drivers with minimal crossover if any to put a pair of these cabinets to work. These have sloped baffles and precut holes for the bass and tweeter. The cabinets are made of 3/4" MFD about 14" high, 10" wide, and may be 10" deep--looking at them they are about one 1 cubic feet rear ported. I can post accurate measurements and picture(s) if I see promising replies to this query to help me with driver and/or possibly crossover selection. Speaker building is not my area. These cabinets are really nice and heavy certainly worth your attention and the Muses will reward you for your assistance.

Seraph

[Godzilla]

Call madisound or parts express to see what they say. Measure the holes for the woof and tweet. They will probably have something that fits right in.

Enjoy!
Godzilla

[audiobomber]

When you net out the 3/4" cabinet thickness, you're at 0.5 cubic feet internal volume.

10" - 1.5" = 8.5"
14" - 1.5" = 12.5"

(8.5 x 8.5 x 12.5) / (12**3) = 0.523 cu ft.

[Seraph]

Thanks for the replies...

I took some measurements tonight. They are 9.75' Wide, 8.5" Deep on top and 14"on the bottom resulting in a 20-degree sloped baffle. Their Height is 15". Tweeter hole is 4.24", woofer 6.75". These measurements result in a 0.6 CF volume considering the 3/4" thickness of the boards. Thanks for pointing that out audiobomber.

When I took the shot I noticed remnants of their past life crossovers and damping material are still present inside the cabinets. What I'd like to do with these is use some nice drivers based on experiences and suggestions of the forum members or ongoing personal research some day! Any help to facilitate the latter is also appreciated.

[vinylkid58]

Originally posted by Seraph
Thanks for the replies...

I took some measurements tonight. They are 9.75' Wide, 8.5" Deep on top and 14"on the bottom resulting in a 20-degree sloped baffle. Their Height is 15". Tweeter hole is 4.24", woofer 6.75". These measurements result in a 0.6 CF volume considering the 3/4" thickness of the boards. Thanks for pointing that out audiobomber.

When I took the shot I noticed remnants of their past life crossovers and damping material are still present inside the cabinets. What I'd like to do with these is use some nice drivers based on experiences and suggestions of the forum members or ongoing personal research some day! Any help to facilitate the latter is also appreciated.

When you first posted, a pair of Fostex FE167E's came to mind, but I see that the woofer cutout is about an inch too big. They could have been used to break-in a pair of drivers while you build MLTL's or something.

Jeff

[planet10]

Originally posted by Seraph
Tweeter hole is 4.24", woofer 6.75". These measurements result in a 0.6 CF volume considering the 3/4" thickness of the boards.

Be a good volume for FE167 alright... i'd forget about the restriction from the existing holes by just making a new baffle to fit over the existing one.

dave

[Seraph]

Thanks Jeff and Dave for the ideas. The hole diameters reported are actually for the flanges. So I think an FE167 would fit. I wonder if a tweeter could also be fit and crossed over using a single cap. That way the tweeter hole would be occupied or would that be defeating the purpose? I like Dave's idea to just fit a new baffle. I was thinking though that would be a bit of work that the front baffles could also be removed and the cabinets squared up with new vertical baffles which would reduce the volumetric to .48 CF or 13 liters. BTW, these cabinets have rear 1.5" ports as well.

Any more thoughts on any of this?

[vinylkid58]

Personally, I wouldn't go any further than Dave's idea of adding a front baffle to accommodate a flush mounted driver. If you have to start cutting those cabs, you might as well just build new ones, that way you'll get exactly what you need and they'll sound better too.

If you do choose the FE167 (this is only a suggestion), you won't need a tweeter, so the existing tweeter hole could be filled by a 3" flared port. Just fill in the existing port.

Or, build a new front baffle for the driver/drivers and run the port out the back. This option would allow you to go two-way, with the front baffle having the matching cutouts for specific driver dimensions.

Jeff

[planet10]

Originally posted by Seraph
The hole diameters reported are actually for the flanges. So I think an FE167 would fit. I wonder if a tweeter could also be fit and crossed over using a single cap. That way the tweeter hole would be occupied or would that be defeating the purpose? I like Dave's idea to just fit a new baffle. I was thinking though that would be a bit of work that the front baffles could also be removed and the cabinets squared up with new vertical baffles which would reduce the volumetric to .48 CF or 13 liters. BTW, these cabinets have rear 1.5" ports as well.

You could use a tweeter to fill in the hole... you could play with hooking it up but i think you may find that it works better without or with a very high XO.

The 1.5" port could possibl=y be reused if it is the right length or longer (depends somewhat on net internal vol after you are done)... in our 15 litre 167 BR we used a 2" port 2.5" long. A 1.5" port would need to be shorter (for the same box volume)

I would leave the sloped front (or just close off the front baffle completely and cut a mounting hole in the back) that is a positive feature.

dave

[Seraph]

Cheers Jeff and Dave. I am enjoying thinking out of the box!

So far I have decided to give FE 167 a try. I would also like to try the flared out port in the tweeter hole. I did a search and found some on Amazon (!) made by "precision sound products". Should this flared out port be of any specific length?

Also measured the existing port 2 3/4 " long with a 1.5 " diameter. For a 16 liter enclosure it appears to have probably been sized correctly or close. What would be a good material to fill the port and the tweeter hole both temporarily for auditioning and permanently if so decided? I am thinking I might even try Dave's second idea at some point to cut holes in the back of the enclosures.

Best regards

Seraph