| 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 |
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| 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 |
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| 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. |
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| 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. |
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| vinylkid58 |
| quote: | 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 |
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| planet10 |
| quote: | 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 |
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| 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? |
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| 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 |
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| planet10 |
| quote: | 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 |
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| 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 |
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| Nanook |
Dave, I'm a little suprized you didn't suggest a restrictive port. Without it, I end up with the impedence peaks of 60, 66 Ohms respectively using WinISD ProAlpha
the internal dims would be equivalent to 8.25" X 9.75" X 13.5" = approximately .6284 ft^3, requires a 4"port, 15" long to tune to 55Hz.Much smaller and you'd definitely hear a chuf or two from the port. Now, stuff it full of straws and all would be made better....methinks |
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| planet10 |
| quote: | Originally posted by Nanook
I'm a little suprized you didn't suggest a restrictive port. |
We just wanted something quick & nasty so we could break in drivers & play with mods... the 167 Fonken is still in development.
Here is the sim of what we built....
dave |
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| planet10 |
Neophone is certainly not as efficient as FE167
dave |
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| Seraph |
Nanook, you've got me thinking.
First off your icon has evolved to a congenial looking fellow from a smiling scull overnight--what gives!? You oughta be a wizard, if you can do that!
Second am I reading that this cabinet would be limited in terms of length of the port if it was to be located in the tweeter hole?
The other question I have is the location of the port being on top. Most ports I have seen are located below the driver. Does it matter if the port is above or below the driver?
I would be able to get the required length and diameter if I enlarged the tweeter hole and somehow patched the woofer hole to install a 4" diameter, 15 " long port.
I appreciate everyone's feedback. |
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| Nanook |
Seraph---well I thought a change might be good. The fellow is Richard Feynman, one of the world's greatest minds ever. (often credited with outting the problem with the exploding shuttle, and the brittle O-rings--although he was the first to admit it wasn't his idea, Nobel laurate, womanizer,actor, musician). A friendlier face to look at. An American scientist of the highest level. I guess I could have used an image of Richard E Taylor, a local guy (from Medicine Hat) who also won a Nobel fro physics..he helped discover sub atomic particles at the Stanford Linear Accelerator Center.
For a thumnail of his life look here. I had the privillege to personally meet him in 1991 or 1992. A very nice man, who stopped at the local university to give a talk on his way home to Medicine Hat to see his father and some childhood friends. He kicked the local media out of his talk, as they were disrupting the it, and it was given for students anf faculty, not the media.
Where the port is located doesn't really matter much. There are successful designs with the port above the driver, below the driver, on the back , some down-firing.
I would do as others have suggested, glue and screw a new baffle to the existing one (you could cut out the front one, leaving an inch to inch and one half all the way around it. This would allow you to place the driver where ever and the port where ever on the front baffle as you see fit. As far as fullrangers, please consider Dave's ideas, he has quite a bit of personal experience.
Also look at his included image. Placing the fullrangers on the rear, "straight" face and the angled one to the rear, is a good option.
If a smaller diameter port is easier...I'd do it. Or make your own "variovent"--a resistive "plug" with no depth required--this would reduce the impedence peak and possible extend the bass. Not sure if Scanspeak, or whatever they call themselves now stilll make em, but DIY types are easy enough, perhaps not as easy to predict the results. If you can run an impedence curve or can generate one , then a DIY variovent would be pretty easy |
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| Seraph |
Thanks Nanook. I am glad I commented about the fellow. The picture struck me as one of a bohemian person. The sun looking tapestry and orangish colored stripes in the background which might be books add to the feel for me. I didn't know what Richard Feynman looked like but I had sure heard of him in school. The link to Richard E Taylor's life is appreciated also and bookmarked. All this is somewhat of a synchronicity for me. I have always been fascinated by quantum physics and just recently visited the Jülich Research Centre and one of their cyclotrons. I too met some very humble and hospitable scientists. The work the centre is doing on the environment stood out for me. It reinforced the importance of our ecosystem in the longevity of our planet...
You and others and have given me things to ponder and contemplate.
I am grateful to all |
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| Nanook |
| is of nano machines, an area of interest for Feynman in his later work and lectures. |
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| planet10 |
Feynman is one of my heros...
dave |
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| Seraph |
Placed an order for a pair of FE167's and some ports...
Hopefully won't be getting too much saw dust in the air but would like to systematically try all suggestions in time...
How long for the FE167 to break in?
_______________________________________________
"The time to relax is when you don't have time for it", Anon |
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| planet10 |
| quote: | Originally posted by Seraph
How long for the FE167 to break in? |
Awhile...
dave |
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| Seraph |
Received the Fe 167's finding them slightly smaller than the existing holes in the front baffles. Am now contemplating removing the speaker binding post cup from the back enlarging the hole for a port and cutting a hole above it for the driver. Trouble is I dont have a router...Will look into buying one if I could justify the cost given the expected usage or may just look into the yellow pages for a wood worker.
Dave, a couple of questions;
1. What is an optimum tube port diameter and length for this 16 liter cab?
2. Do you or will have Fonken cabs for the 167 any time soon?
Regards
Seraph |
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| planet10 |
| quote: | Originally posted by Seraph
1. What is an optimum tube port diameter and length for this 16 liter cab? |
2" ID 2 5/8" long
| quote: | | 2. Do you or will have Fonken cabs for the 167 any time soon? |
I have a 1st draft,
dave |
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| Nanook |
or should be to most thinking men of the planet. I wish I had a smidge of his intellect and creativity...Oh well, the world needs idiots like me too
':)'. We can't all be described as the "best young physicist" by none other than J. Robert Oppenheimer.
Seraph, glad you made a decision, and what I think a pretty good one to boot.
regarding magic, it's easy. Just think it and you become it... |
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| ped |
Hi dave,
Do you have any more info available relative to the speakers you posted a photo of in post #9? |
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| planet10 |
Sealed FE167e crossed over to an active pair of push-push Extremis woofers. Red Light District on the top, Bryston 4B on the bottom. XO is at the -3dB point of the sats (106 Hz) annd is accompished with a smaller coupling cap on the RLD (for a net 3rd order) and the low pass on the woofers is using SY's as yet unpublished gyrator-based tube XO (i have REALLY good fealings about that one).
These were for a friend of SY's in CO. Centre is also a sealed FE167. Surrounds are FE127 ML-TLs built into the wall & ceiling (all driven with 2 more RLD)
dave |
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| Seraph |
Had a taste of fresh magic the other night after deciding to give the drivers a listen in the cabs existing holes... Figured I could have a listen meanwhile the drivers are breaking in and I am deciding what to do for an enclosure. So just installed the drivers and filled in and sealed off the gaps with blue tack. Closed and sealed off the tweeter holes as well using blue tack and two circles cut to size out of an old mouse pad! And in less than a couple of hours I had the drivers mounted and wired directly to the binding posts smiling all the while at the crudeness of the whole process. And soon the speakers sat on a couple of stands to be driven by 41Hz Amp 6 and a tube hybrid preamp the marriage of which is heavenly. Then there came the moment for the first few notes of “Brand New World” [Cowboy junkies—“at the end of path taken”] played through my modded work horse JVC Z1050…and I was immediately struck by the immediacy of sound stage depth and width, the truth of timbre, and clarity—the absence of haze imprinted on the precious signal by crossover components. Music has been nonstop since then as the latent magic continues in its gentle subtle flow and the drivers are breaking in. I will probably but patiently do rectangular boards secured and sealed on the front baffles with properly sized holes for the drivers. The hole for binding post cup in the back is really too low to be feasible for an enlargement…
Thanks Nanook (and Dave for feedback) for the encouragement to just proceed. What I did is an example of how making do with the resources at hand with little effort can produce outstanding results. The secret only lies in doing.
Those who are considering FR or any other purist scheme—make haste, music is upon us! |
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| planet10 |
| quote: | Originally posted by Seraph
Had a taste of fresh magic the other night |
:) |
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| Nanook |
| quote: | | Had a taste of fresh magic the other night |
excellent. "Take a trip (to BC) and never leave the farm"--ain't that a song or something? ("and they call it the streak")
Really just cut a baffle for the drivers and glue and screw it to the front. And welcome to the dark side:darkside:. There is no going back... |
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