grindstone

Are K-horns all 3/4 stock (I mean, the old ones before MDF everywhere)? I can't swear to it (memory), but I thought only the baffle and front were 3/4 and the rest was 1/2 (???) when stock was ply. I think anybody who has been serious and open-minded about cabinets would at least entertain the idea of investigation (if not dynamat). No offense intended to anyone, but I like inquisitiveness...

The short answer is that it's your experiment to make. First longer answer is that I have noticed that behavior & geometry too when breaking down the (65+ yr old) EV regency, although not a fronthorn. Second bit is that hornresp has been trustworthy in my 14+? yrs using it Provided You Understand what it's really simulating and how different actual conditions and geometry are. If you can build a straight cylindrical horn 5 ft long that all radiates into one pi conditions, your power response will have strong similarities to the simulation. If you think about it, radiation near the xo point will likely be into more nearly 2 pi conditions, so there will be a transition region. If your design modifies the straight horn to fit into more typical living room conditions, expect other changes that may not be directly modelable in the available segments in HR. Beyond that, there's the business of any driver's response not being flat in and of itself. Now, presumably you will stick this low frequency unit in some room which will have its own room gain and standing waves. Then there's the business of group delay. Then there's that pesky crossover with polars and directivity. All this is just DIY audio You will need to do multiple simulations and adjust for things in your head and/or use more sim tools and measurement. In the end it's your labor and money and sawdust. Good luck and please keep us posted. HR is always right for what it does, we just never build what we can model with it.

Edgar I feel for you. I don't really see any way out of this from the sounds of it. On the upside, you should have access to some really sweet drivers at a discount pretty soon...

...which is one more reason that I am grateful to our sponsor for this place. And in that spirit, a quick look at Cohen's book indicates 7.4 cubic feet for 15s...

Yeah, but it's a dry cold Nothing like the stillness & quiet and the sound of footfalls. I'm sure it's all very funny to the Canadians, though. "Those banana-belt guys think _that's_ cold!". I'm pretty sure people who live in the Northwest Territories wouldn't much notice any difference. Tough to beat the air quality/asthma index we have going for us, though. Be well--we can ride motorcycle in the 30's on Friday

Yeah I'm about where you are, just a piece east. My 19 yr old civic wouldn't pop this morning. Got the charger out but the way the (plastic) hood release feels trying to gently work it, it's going to be a while before I can try it. Sucks. Got two baby cranks outta the old girl, but it takes 3 or 4 to pop in this stuff. Thought I'd get lucky. So I suppose I have some time to read the forums right now. This would be why there are garages (that shouldn't be full of stuff :)

Yeah I'd like to hear any comments from Jim as well. In fact, I found this thread searching for some reference substantiating my (ever-increasingly-failing) memory regarding PWK poo-pooing "reflex horns" somewhere or other.

While you're in there, it's maybe worth physically (not electrically) inverting the woofers when you re-install them. You know, for the next 42 years of their (surrounds' & spiders') lives...

Nice, thanks for sharing. I've always had a soft spot for wide-rangers, too. Just running my mouth before enough coffee is down to think better of it, but my first thoughts were wondering: (a) if there's some sympathetic woofer/box excitation going on with the c-scala boxes/cones/port (b) maybe(???) some beneficial baffle-width stuff, too (asymmetry and all re the AN "baffle" it sees, although collapsing directivity maybe washes that away???) If it's not a pain and a half to do so, it'd be interesting to know if they sound discernibly different with the other big boys moved some. In my own exp hacking-up other stuff, (I'll call it-) "physics" seemed to be going on amongst the various boxes and weird room/schroeder stuff. Way different rooms, but I put my hands on the Cornie cones with other stuff playing and stuff was happening. I know, "stuff" is way too technical jargon but I don't want to start an empirical anything before I wake-up :)

oy. mr cornies are screwed but i await the Preponderance. Pssst: do what it needs : )

Thanks a lot for posting. I'll not opine about wool vs. dacron but instead invite everyone to form their own conclusion (in the hopes that they test multiple materials). One thing I've done in the past is to solder the speaker leads to the terminals and then lift out the woofer with live program material so I can mess with lining/stuffing through the woofer hole. For a couple hours at a time. And multiple times. Alternatively, when you're (one is) doing DIY stuff, you can leave the baffle for last gluing. Rope caulk is better than a bead of RTV for that (don't ask--you'll be sanding RTV for ever). Put the speaker on its back. The balance is between "openness" of soundbodies (think cello or piano) and "tightness" of percussion. You have to flip program material to extremes and find the "best compromise" (tm?). The super-low-Q "tight-tight" drums are packed with R19 (etc), the most echo-ey soundbodies are empty. All that _If_ you guess right on your tuning. In some (?) 35+ years of playing diy-speaker-genius-pretender, I've missed every single box tuning at least a little bit. There's only one tool--restriction of ports--available at that stage. And it costs efficiency. The moral of the story is to almost never tune for "flat" (it'll boom in-room). EBS is the way. TL's. Slow-rollers. Then "tight" isn't anything but a number. And a goofy grin with the right material. Giggling, if you get lucky with sweet wood. Bracing matters, and it matters so much more than most people know. Stiffness matters. Great plywood matters. Once you hear great plywood against (?) p-board or mdf, you can't "un-hear" it. Yes, I know these bald-assertions are likely to get me well-lit-up (especially in a place where the ante is 5000 posts). They're also my experiences. If you have a driver larger than 5", it's _always_ worth it to buy the best plywood you can find. Marine-ouch--the word marine is painful--but if it's the best, it's worth it to your project. Look-up the stiffnesses (moduli). It's not even close. I've learned a lot from various people around here that post theirs, so I'm cutting-open a vein to try to pay some amount back to this wonderful place. Can't really remember exactly when, but I once attended a demo at my local Audio Society meeting a good 20-ago. Mike Dzurko remarked that night that the single biggest thing a DIY guy could do was make a crazy-great cabinet. I've learned that I agree. A manufacturer cannot possibly "get paid" for making a great great cabinet. I've seen people say 8" spans. Personally, I'll use other materials (if weight matters) besides great-great-ply, but I also will brace them every 5". I think it was some time spend on OB stuff that got me to ask the questions (and pay for the experiments). There's a _lot_ of good stuff to be had w/o much work or expense. Thanks for the time and the audience. Let the beatings begin.

Grand spirit. Everybody who goes through the work says it was way more work than they knew but they always seem to say it was worth it. I tip my hat. When you go bigger, the center-to-center has to increase and that can both hose the pattern-matching and tilt your forward lobe. Fiddly bits lie that way--again I tip my hat--you are a braver man than I! I love this place. It's the biggest bunch of enablers and instigators this side of Audiokarma : ) PS I swear we've all had that roomate once in our lives...sigh.

erm, starship-trooper? that's a whole Other Deal! best, though! grindstone

post has been flagged for removal, so if anyone has any "captures", well, it'd add value t5o this thread.

Wonderful-thread! What I have to add is that, there is _no_ _such_ _thing_ as a box that is too-well-built. Yes, of-course, angels, heads of pins--all-that. It turns-out to be about Stiffness. Marine-ply. Or perhaps Baltic-Birch. Many-many-layers. The research has been done. It's Out There. I'll not "advocate" for a single thing -- except (perhaps?) that anyone (everyone?) should take the Time to research the Problem. Hint: keywords -- "modulus of elasticity" <-- aka Modulus. Upshot? Use _great_ ply. it's _always_ worth whatever it costs!!!

Understood. Life happens. The people on this board are the most amazing collection of helpful resources that exists anywhere (as near as I can tell). Please keep posting even if your're only in consideration of this or that. I learn so much from these people (pretty sure I'm not alone) that it's staggering. Dialogue. That's all it takes, here. Wisdom is dispatched from so many. I just can't even thank Klipsch enough for providing the resources to run this board. Crazy-great-stuff. Every day. For free. Back-up the truck and Buy Klipsch!

Maybe this has already been-done (in which case, I apologize and ask the mods to delete this thread). If not, I just have to sound-off about the contributions of WMcD. Over and over and over again, those posts are invaluable. I just can't say enough. On a board with amazing contributions (in the thousands of posts) from all-kinds-of-people, well--you guys know who you are. And you know how cool it is that you all have shared sooo much knowledge for so long. Today, it's about Gil because I've been so moved by his contributions. Bravo!

Maybe kind of a "bump". Wondering if you've made any decisions. Can't see selling my own Cornies but I also should say they're not even wired-up (EV Georgian khorn clones have the wires). I think that wvu80 had a very good take and I'd encourage you to investigate. If you repackage the bass unit (or add a sub), you can end-up with quite fine sound for a small-ish outlay. Then, you can just watch and wait for some Cornwalls (and have some fine sound while you wait) or take your time on a Cornscala project or whatever else. Good luck and keep us posted.

This must be mine--erm,...it's my opinion that they solved different problems in different ways (at vastly different historical times). And I still think the one thing would be a wonderful top for the other thing. I think it would be poor form to say more than that I love Klipsch, I'm happy to own their stuff, and that I'm grateful that the company provides the resources to support this wonderful community.

Open to correction as I am not familiar with those. Do they offer C1 to C10 at 106db/w cleanly at the same price as basic K'horns? Serious question, as I honestly have not heard of "...another major breakthrough." Dave Yeah, Tom Danley is for real (and a great guy). Changed the world and stuff. But I always thought if you had the house/room for khorns, that SH-50's would make really nice tops for them. You wouldn't have to run the basshorn so high and you basically would be "done". His partners don't approve of offering home hifi products, or at least they haven't historically so their aesthetics remain "road" and flyable.

Heya Freddy! Cool to see you here-abouts. Didja lose the first 2 K 'nyms here in the last few decades? : ) Carry-on : )

Maybe another way at this is to make more room for a basshorn by using a runt on top? Assuming those are maybe half-LS-size and relaxing the size a little, maybe that works in the footprint? FWIW.

Nico, this was a moving thread. My old man has been gone a looong time but it took me a looong time to be able to finish your threads because I had built something with my old man the summer before he checked-out. And man we were at each-other and hard! But it wasn't young-guy vs. old-guy-stuff--not at-all. It was...umkay, here's this _SAME_ guy that MADE me have Every- (single-da**ed-) thing square and plumb and level and cross-chalk-lined and double-checked on atomic clocks for my whole life--here's this Same-Guy saying "ah I don't buy green bananas anymore--Nail it!" . . . (that'd be ellipses "for-effect" to try to say how it Rocked-me at the time). Not-so-much-audio, I know. And I know I'm _quite_new_ here, but I've grokked the support that the lifers on this board can throw-out in time of need--remarkable group, this--well, when you're not engaged in arguing the same arguments that Everyone (except us newbies) _knows_ to Not Even Bring-Up Nico, thanks for spilling the "non-speaker" bits, too. You got to have an experience that not everyone gets. About all I can muster is "Salute!" Thanks must also go to our forum sponsor, however "ill-timed" on my part. I just can't say enough about Klipsch which supports all this effluvium with the heavy-lifting of forum-management. Klipsch still "gets" that there's a "human bit" in audio -- and they foster a space for it to "just be" -- whoda-thunk? THANKS. Customers for life? Oh yeah.

Haven't had time to do any justice to this thread but wanted to raise a couple thoughts. In a way, this is a sort of drive-by (tax week and I'm still working on them!) because I can't take time to find all the supporting links. Basically, if you pound the web about c15w's, sooner or later you hit Greg Monfort's (among others) post about the earlier ones (green & gold) being different than the later ones (black, like WMcD's auction link). Seems Nico is one known owner of one of each, but he probably lives farther than it pays me to ship a woofer tester even If he'd help us. Maybe cart before horse on that, so on to a second point. The anecdotal reports just don't "seem" (IMO, and mine only) to track the sort of sims we're getting. The horn is the horn and I've not checked Edgar's or X's models at all, I just remember what I got when I modeled it (with Mr. Janni's < known bad per Dennis > data). I mean, the horn is the horn and we can all get close to modeling the horn in our 1-D worlds--we should all be "in the hunt" with respect to the reports. Just seems like it's not--the sims vs. the anecdotal reports. And I agree about the Le, esp in series. If someone who owns c15w's and is following this thread is game, maybe there's a way we can get some more data and I'll do what I can to get it done. What we're seeing in most of the sims is 65/70Hz horns. I think the consensus (?) is that it's a 50-ish Hz quarter-space horn. Check (was it?) D-man or (??) Q-man or (both/neither?) that did the Deans. Somebody else -- Armando as I recall, had a bottom with some EV stuff on top arranged highboy (?) My impression is that there is "some bass". It'd be great to hear from them if they're around. So if the horn is the horn and the results aren't tracking, I'm thinking we're not modeling the c15w right which means we need more numbers. Parenthetically, the throat geometry, angle-cuts and all, may in-fact Be part of what makes these things what they are. Pretty-much nothing parallel until the 4" sections (mysteriously-absent a reflector). < X -- if you're out-there, can you readily/easily change the first corner 90 expansion to having a reflector in it for any of your previous sims just to have a comparison? If it's unwieldy, skip it. > I searched "period literature" and exhausted my own stuff hunting for response curves for the Classic or Dean and struck-out. There's oodles of curves for the models After these, but I'm batting .000. This is the best I can do, but I trust Steve and Bruce more than I trust WT3 data (at least _my_ personal WT3): http://www.audioasylum.com/forums/hug/messages/4519.html There's probably also something to be said for another 15 years of suspension-stiffening since then--after their first 30 or 45 Soooo, say I swag my Sd at 13.5" diameter & I trust Mr. Janni's Cms, Fs, Qe and Qm (and yeah, Le is my own arbitrary value). Out of my keester, I say 15 ohms is what I get when connected on "10-20 ohms" which needs 3.87 V into it from the generator to get a watt so that's the Eg deal. This is what I get from a fresh/quick hack (gray/background is masked resonances like Edgar's shallower chamber, black is 30" chamber length honking like gangbusters). For those who aren't hornresp users, those resonances are pretty strongly overpredicted as given by the preponderance of sawdust. I'll grant that the moving beeswax seems spooky-light for something with two coils (and apparently two spiders), but it's what it is. Could be I'm all-wet, but I think it's the difference between caring a fig about this horn and not. I think Mr. Cohen knew some stuff and I'm still trying to catch-up. There have just been so many reports about liking this horn that it seems worth some investigation. Aw crap, I just helped that dude's auction and sealed my own fate at Never having any of these woofers, didn't I? Wow, what a ramble. Well, almost anything is more fun than finishing my taxes. Thanks for the space and the time.

One more thing. You're the akabak-Meister, but I would think the quarter-wave of the chamber would be the height of the chamber--the only two parallel walls. OTOH, the driver-itself occupies so much of the chamber cross-section that I'm not sure what dominates.