Bill's website/blog seems to have lost the full plan of the backload K-horn, too bad, perhaps he'll put it up again. I may have it saved somewhere though. Really something I'd like to build if I had the need or the room. The better Fostex or TB 8" would be great, but my first choice would be an 8" coaxial if I could find one with the right specs, which I have yet to.
IG
IG
IG,
I think between the images on posts 19 & 20 there is enough info to build/model it. What is the recommended driver or driver specs? Low Qts and high Bl type drivers? When I have time I will try to build the model of this BLH with the K-slot.
I think between the images on posts 19 & 20 there is enough info to build/model it. What is the recommended driver or driver specs? Low Qts and high Bl type drivers? When I have time I will try to build the model of this BLH with the K-slot.
IIRC, it ran things like 225 (?)/206/208, Lowther PM6 ? - here's the front dimensions - so I'll have to look in old computers for the plans
http://img81.imageshack.us/img81/3363/al3hb9.gif
http://img81.imageshack.us/img81/3363/al3hb9.gif
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I did no check that link, yes that seems right. There also has to be some bracing added to the last section before the mouth.
As freddi said, either the old FF225K, FE206En or the 208 should be good here. It should make for a pretty sensitive system. I really like my small FF125K and bought the very last pair Solen had in stock when the series what discontinued, wish I had grabbed some 225 for use in the small Karlson SK8 or the K-horn that I'd like to build someday.
IG
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It probably ought to have been called a F-slot horn in honor of Norman C. Fulmer as Karlson put the slotted chamber in front of a driver.
An externally hosted image should be here but it was not working when we last tested it.
hi X - -re: Bill's blh, here's some stuff - I may have more - on the AJ-Horn sim below, I used RCA-Fan's input - not sure how he arrived at that
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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more...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
A couple of minor details to be settled, but yes, I'd be ready to cut some wood any time for this one - for some reason, I got a really good feeling about the 10P, and would like to have at least one or two boxes ready to populate when we get some drivers in our hands.
Since it's now in public conversation, this might be a good time to repeat what I've said many times - that while "not all enclosure topologies / designs can successfully be scaled to fit a different choice of driver, dimensional constraints,etc" - sometimes, if the math is right, they can. We'll see .
It's not so much a matter of scaling as designing it in the first place. 'Scaling' can be achieved in some cases if you know what you're doing: the trouble is, 9 times out of 10 it's rather more involved than is happily imagined, and therein is the source of many problems.
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Thanks for all the posts gents.
The Karlson slot cabinet certainly looks doable with the 208, as does the Haruna with the 168. Must admit, I do like the idea of the Harunas simply because of the size, plus I'd be able to attach a horn HF driver to the side. However my other half isn't as keen because of the size.
What is the general view of the Fostex published design for the 208 (that I liked to in the OP)? Are they likely to be as success as the the Haruna and Karlson ones? IE is my short list 2 or 3 if you see what I mean.
The Karlson slot cabinet certainly looks doable with the 208, as does the Haruna with the 168. Must admit, I do like the idea of the Harunas simply because of the size, plus I'd be able to attach a horn HF driver to the side. However my other half isn't as keen because of the size.
What is the general view of the Fostex published design for the 208 (that I liked to in the OP)? Are they likely to be as success as the the Haruna and Karlson ones? IE is my short list 2 or 3 if you see what I mean.
The standard Factory cabinet for the 208Esigma isn't bad -it's one of Fostex's better efforts actually. As for whether it would be as successful, it depends what you mean by successful, i.e. what your technical criteria are.
The three boxes couldn't be much more different, so meaningful comparisons are difficult. Karlson type boxes are something of a love / hate thing. Some people, once they've heard one, can't live without what they do. Other people loath them since they are somewhat idiosyncratic. To an extent, the same applies to back-horns, albeit not necessarily for the same reasons, and of the two mentioned, the in-room power-response will be very different given the terminus configurations -a single, mounted close to the driver in one case, and an MTM in the other.
The three boxes couldn't be much more different, so meaningful comparisons are difficult. Karlson type boxes are something of a love / hate thing. Some people, once they've heard one, can't live without what they do. Other people loath them since they are somewhat idiosyncratic. To an extent, the same applies to back-horns, albeit not necessarily for the same reasons, and of the two mentioned, the in-room power-response will be very different given the terminus configurations -a single, mounted close to the driver in one case, and an MTM in the other.
As a Karlson enthusiast, I'll be the first to admit they are indeed quite polarizing and I can understand that. 🙂 The RCA-fan back-load K-horn has nothing to do with an actual Karlson though. I can not personally recommend any of the enclosures in consideration, but don't let the K-word turn you away in any case. 😉
IG
IG
the original Karlson cabinets in the two upper sizes K12 and K15 can sound very good - its driver dependent. New couplers can be developed which are good - adjustments can be made though starting gap and aperture flare changes. The simple K-tube tweeter is brilliant in its range. I think Greg B's Karlsonator family would be one new way to go if one wants more LF extension than Karlson's K8 and K12. I have 5 different pairs of 12 coax which have lived in K12. There's a bright future for Karlson in diy audio - if anyone ever takes the time to make and learn them.
be nice to see data (vs. so much of Everything Else)
Phew...tough-thread. Still, gotta pipe-up. Few things:
Preliminaries:
Freddy did well on the RCA-fan backhorn excavation (as-usual). The only addition from me is perhaps an original/designer's baffle drawing. Seems ~essentially indiff from prev. posted included more for Posterity (attached).
This, to the point, is the bit where the hairball goes down hard.
Bill has been openly sharing for 20-plus years. GM, others, near as I can see, about the same. There's a point where guarding vs. standing on shoulders must be reconciled. Younger-guys, well, be nice if they might get to it a bit quicker, is all 🙂 They'll be saying it soon-enough if they aren't already.
Floor-closure-resolution: Fair-shake -- reprint Bill's "announce" verbatim (check Wayback if you should like):
"Here are the plans for the RCA-fan backload horn, as mentioned many times on Audio Asylum forum and elsewhere. This horn is the result of many backload horns I have made over the years for profession [sic] use at Yorkville Sound. This particular model was built 13 times, each a little different from the last to get that motion picture sound of the big "W" horn systems in the 1940's theaters (The famous Shearer system).
The plans are free for home constructors, but NOT for commercial use."
Editorializing:
Soooooooooo..... if anyone is scoring at home, well, they'll need 13 to ante 🙂
(1) Two-words: "thirteen times" -- in wood WITH DATA. Thirteen.
(2) sim/talk whatever you want -- see (1)...carry the one..."13".
Erm, plane-wave 1-D what again?
Phew...tough-thread. Still, gotta pipe-up. Few things:
Preliminaries:
Freddy did well on the RCA-fan backhorn excavation (as-usual). The only addition from me is perhaps an original/designer's baffle drawing. Seems ~essentially indiff from prev. posted included more for Posterity (attached).
This, to the point, is the bit where the hairball goes down hard.
Bill has been openly sharing for 20-plus years. GM, others, near as I can see, about the same. There's a point where guarding vs. standing on shoulders must be reconciled. Younger-guys, well, be nice if they might get to it a bit quicker, is all 🙂 They'll be saying it soon-enough if they aren't already.
Floor-closure-resolution: Fair-shake -- reprint Bill's "announce" verbatim (check Wayback if you should like):
"Here are the plans for the RCA-fan backload horn, as mentioned many times on Audio Asylum forum and elsewhere. This horn is the result of many backload horns I have made over the years for profession [sic] use at Yorkville Sound. This particular model was built 13 times, each a little different from the last to get that motion picture sound of the big "W" horn systems in the 1940's theaters (The famous Shearer system).
The plans are free for home constructors, but NOT for commercial use."
Editorializing:
Soooooooooo..... if anyone is scoring at home, well, they'll need 13 to ante 🙂
(1) Two-words: "thirteen times" -- in wood WITH DATA. Thirteen.
(2) sim/talk whatever you want -- see (1)...carry the one..."13".
Erm, plane-wave 1-D what again?
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Sorry, misread the post; I thought it was referring to Karlson boxes, not Bill's Fulmer slot cabinet. In which case comparisons are slightly easier. I'd take that over the Factory design (although the latter is reasonable for what it is) any day of the week. Along with Ron Clarke's Dallas II, it's probably the best relatively compact back horn for the 8in Fostex drivers out there, although they've got somewhat different design goals. Comparisons to Haruna won't get you very far, since the configuration is completely dissimilar, and they don't even use the same size drive unit, so YMMV on that score.
Grindstone -other than recommending Bill's design (the quality of which requires little further comment from the likes of me) I'm afraid I couldn't follow your post very easily. Perhaps you could clarify it a bit?
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Thanks for the reply, Scott. No, not recommending Bill's design over/above anyones -- just trying to honor the foundation and the spirit of the sharing -- same as the spirit in which large numbers of your own designs have been shared. Historically, people have expended large degrees of effort and invariably it all comes-off as wrong. Call it a poorly-constructed testimonial to period-appropriate reception. The work is the work (which is, in many threads, what you've alluded-to). My goal is to reiterate that the bar moves with time and that even half the number of builds would be heroic by current standards.
You're not kidding. And however good software is, it'll never tell you exactly what something sounds like, nor is it a substitute for building the thing, and thereby following the time-honoured process of grind, refine, measure, redesign aspects if needed & repeat. Which isn't to knock software -it's a useful tool & can save a lot of time & effort by getting you in the ballpark quicker than might have been the case. But unless you're v. lucky, it's not going to be the last word either. 😉
Grindstone,
I am new at this so if there are already models or simulations of the Karlson slot back horn, I won't bother modeling it. From what Freddi said, I thought no one has actually modeled the Karlson aperture yet. ??
13 times with data - perhaps you can point me to the data.
I am new at this so if there are already models or simulations of the Karlson slot back horn, I won't bother modeling it. From what Freddi said, I thought no one has actually modeled the Karlson aperture yet. ??
13 times with data - perhaps you can point me to the data.
I've not seen published data on Bill's previous blh which led to this cabinet. His AJ horn sim input is probably a fit using a rectangular opening but not real far off. I may have a picture of Bill's "chimney" blh but am not sure if its part of his Fulmer slot blh project. I'm not aware of anyone modeling the tapered aperture.
When K-nut Carl gets onto a build of a real Karlson-type, a number of things are tested including multiple sets of wings, vent, lowpass choke adjustments, etc. Then once that's built, he goes again and tries to beat it - sometimes just making the rear chamber a bit smaller, a fully curved reflector, an oval K-tube (based on Karlson's Open End Waveguide patent)
When K-nut Carl gets onto a build of a real Karlson-type, a number of things are tested including multiple sets of wings, vent, lowpass choke adjustments, etc. Then once that's built, he goes again and tries to beat it - sometimes just making the rear chamber a bit smaller, a fully curved reflector, an oval K-tube (based on Karlson's Open End Waveguide patent)
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Looking at the Fostex recommended BLH for FE208EZ, it's not too far off from RCA-Fan's backload K-horn, AFAICT. Similar internal folding and overall bulk. They'll certainly sound different in the end, but both could be good choices.
I'd really like an 8" woofer with specs similar to FE206EN to run in the backload K-horn, along with a good CD on my Transylvania Power Company "The Tube" which I would mount inverted at the top of the horn mouth. A de-whizzered FE206EN might do, but still would feel like a waste of bandwidth. Most pro 8" have too high Fs.
IG
I'd really like an 8" woofer with specs similar to FE206EN to run in the backload K-horn, along with a good CD on my Transylvania Power Company "The Tube" which I would mount inverted at the top of the horn mouth. A de-whizzered FE206EN might do, but still would feel like a waste of bandwidth. Most pro 8" have too high Fs.
IG
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