grindstone

Mr. Hunter - if you have the inclination to comment, that Annapolis Rebel chamber pic has been working on my head. What I wonder is if the holes are the throat or an absorber chamber to smooth it out...or another resonator to load it under cutoff. I can't find the exact references, but IIRC PWK had commented at various times about porting, too (ala maybe Novak and even Roy later/now) to protect the driver a little below where the horn unloads (although the pictured ones are much too short for that). Is that thing a "normal" Rebel 1 (or was there even such a thing)? I just threw a throat adaptor in my little Hornresp model of what I've guessed (from the patent) to be a Rebel 1 and sure-enough, it works more like the later Rebels. It still unloads pretty high, but it kicks butt in its limited bandwidth (like seemingly everything the man did). All I could really glean from the '53 K26/7 brochure was he was talking about basically acoustically lowpassing--like the other Rebel "LC-stuff" in the Small Corner Horns article. So were the earlier (40's) ones the same thinking or did it evolve to that in the 50's? Thanks for taking the time to read and for all you do!

A worthy crusade. Wish I was a few states closer. Only gutshot I've ever seen posted of one of that rev. Should probably ping @JRH

Yeah if you don't know a chemist for something really crafty, my hunch is to figure out how much libation supply you have and call some buddies to get it tipped. Anything thermal and you might hose the structure and make yourself a schrapnel-generator. Something super-high frequency would take too much energy for that much stock. I'd try the slippery or penetrant angles, but I'd work really hard to find a real chemist because preceding substances (in event of failure) might limit successive options. Absent any of that, you can find gun drilling services at certain tool and die shops--a hole through the projectile might let it all move enough to release a little. If nothing else, those guys have arbor presses and stuff to pop it out, too. I don't know anything about cannons, though, which is why a chemist to steer some acid just weak enough to not harm much makes sense. If I didn't care about it so much, I'd plug what I could around the ball, tilt it, and pour a liter of coke in there and walk away for a couple days...I don't know if CLR etc would be too strong of an acid not to have to flush pretty fast. It's just too much material to heat, too. Bottle-jack plus extension?

Any chance that U is a W--can you post a picture of the labels/backs?

Thanks for the reply and for the pic. If you think you're already used to them and find something or other wanting, let us know. People's tastes are very different so it's hard to say anything useful until we know what we're trying to fix. Mess with placement and toe-in. Room corners will get you more bass if you have the option, but it's fiddly (and less-practical with their size). Cornwall bass is comparatively better-damped than a lot of vented speakers so it can seem light--if that's your issue, some people add subs. Swap receivers with a friend for a week if you can. Drop a tube amp in for a bit if a friend or nearby forum member is willing. Your stuff should be plenty fine to give a fair shake to the speakers if they're working right. Putting together a system is as varied as there are people, so it's best to know what you're after. If you don't know, that's fine--most people cycle through a lot of stuff, it's just inefficient and costlier than it needs to be if you know where you're going. There are lots of people here with a large variety of rigs using Cornwalls. Everything does something and costs something else. There is little agreement about anything in audio. Follow your own ears. I have never once heard the verticals so am pretty hesitant to start taking pot shots. What I can say is that I had cane grilles, too, and had to have the grilles off when I listened, FWIW. I know this post is effectively useless, but didn't want you to think we'd abandoned your thread. There's a really good group here, they're just in stealth mode or stuck arguing in the Lounge

Woooo...that apple ply belongs in the Art Appreciation thread, too.

Welcome. Congrats are always in order for anyone landing Cornwalls so Congrats! I'm not sure I slept much the first night I had mine so I get it For now, just keep reading and maybe post some about what kinds of things you play in what size room and how loud...and outta what kind of amp. And if you can put some words on what you'd like to be different/expectations, that'd help immensely. There's a truly staggering amount of information and knowledge here. Seems half the known world population will tell you what they think you should do with your speakers--it's audio after all--the thing is to figure out what's important to you. Are there other speakers you really like? Not prying, just fishing so the members have more to go on to try to assist. Also, we like pictures. A lot :)

How do I tell if my CD improver is fighting my resonator extraordinaire somehow so that the resonator isn't broken-in right? My own 2c about drivers (only): Don't know when it happens, but I can attest it happens for compression drivers and it's not subtle. Woofers, I can never notice. Measure tiny changes in woofers with use, sure, notice, nah. Too many other variables as always in any science with humans. Upper-tier products targeted to (far) "eastern" markets from the 3-letter West Coast company has +0.5/0/-0.5dB switches in the "presence" region, which about anybody here knows is more fiddly/discernible than other bandwidths in which humans try to detect half a dB.

I tried. Made it about a minute and a half. Pitched a transcript in a text file, FWIW. greg_timbers_transcript_erins_interview_052522.txt

Maybe it's because it's ported right into a Lascala, but I'd be interested in your guys' impressions of this H4 video vs. your own experiences.

Sincerely feel for the employees involved in uncertainty and stressful times. I don't have the energy to dig into holding companies and licensing to try to make sense of anything corporate anymore. I think people dice-up rights to names they use to market things but it's all been long-past intelligible for 20 years to me. https://www.klipsch.com/news/pac-response-to-onkyo-bankruptcy-filing?fbclid=IwAR2VIpJg2NiCSsafiWl89-e9VsddakwVwpU4xusC3IdOFFQ7JAV_obxUxYc

Congrats on your acquistion and good on you for inquiring about restoration. Glad you saved it. +1 to all of JohnA's post. No clue, personally. Yeah this'll be fun to watch. We should guess before Jim spills the answer--103 stephens and SAHF seems safe (and later than the WE tops?). What'd this be, 93 after the first 15 or whatever that was? So not early-early, just early. No clue. Maybe 15wk if they replaced it with an EVM15L. On the edge of my chair. Does that say K35D and finish 313F (or A maybe)? Love it. Thanks for posting and welcome. Hang-out for JRH's input before you do anything (except maybe measuring every board you can as it might help Jim).

Here we go: https://news.mit.edu/2022/low-power-thin-loudspeaker-0426

RANT: I don't know why this stuff is always so hard for people. 1) Panel resonances. Vibrating panels radiate sound into a room. They are sources. 2) Vibrating panels are loss. You put energy into your terminals and somewhere acoustic power comes out. Exciting panels may/not help, but "warmth" & balance change when panel vibration changes. If you stiffen a cabinet, both your head and the speaker need rebalancing. 3) Standing waves. Parallel walls, in our current universe, produce them. Braces/filling/lined braces can alter them. Where drivers/ports/PR's etc are located with respect to nodes/antinodes is part of the "soup". 4) Rear-radiation from drivers relects around inside the box and comes out through the cone and cabinet walls again. Changing lining/bracing/filling changes this bit of the "soup". 5) Damping (as in driver) is affected by all the preceding in addition to everything we're not even talking-about. Yes, designers listen to the products they toiled on and Somebody made the final call (prod mgt, eng, team blah) and called it Good. However it shipped--it was a package not to be altered (or it would've had different pricing/configuration). That doesn't mean you can't change it, it just means it's your speaker and not theirs. Anyone can perform some reversible experiments to convince yourself. You want to know about cabinets, build an OB setup. You want to hear what comes out through a cone, toss a portable audio source (phone/radio/etc) inside your (non-running) speaker and listen. You want to know about bracing--add external clamps, listen for a week, and take the clamps off and listen. You want to know about panel vibration--knock at a cabinet corner and knock anywhere else--do they sound the same? How stiff a cabinet of what construction would it take for every spot to sound like a corner? You want to see standing waves, watch some here: https://www.youtube.com/watch?v=VrgyKFBPQW4 Once you hear this stuff you can't Unhear it. Ever. Convince yourselves. Measure if you can/seek to. Nothing is any different than it ever was but people still think this is all voodoo and a crapshoot. It's not voodoo, it's just inter-dependent and non-trivial to analyze. Ask non-audio people which sounds cleaner or better or whatever it is you seek to improve. If just curious, diy some test mules for the purpose and burn them when you are done--if your ears work and you repeatedly try 2 types of material (large soundbodies like cellos/pianos as one, heavy percussion as the other), you can hear night and day changes when altering filling/lining/bracing in about any "normal" cabinet larger than a couple breadboxes) as you change things. END RANT. (And stay off my lawn) To the OP: Applaud your curiosity and open-mindedness. It may well be that the way it is is the easiest thing and if you are happy, then you have Succeeded--they are Your speakers and all that matters is that you like them.

"A good friend of mine used to say, 'This is a very simple game. You throw the ball, you catch the ball, you hit the ball. Sometimes you win, sometimes you lose, sometimes it rains.' Think about that for a while." Ebby Calvin "Nuke" LaLoosh

+1 Welcome. Congrats on your acquisition and sorry You'll need to investigate more. People here will steer your investigating if you need assistance. If you are comfortable sharing your location, someone from here may be near-enough to help as well. We all just need more info to provide proper direction.

I feel your pain and wish I had your EE chops. I don't know how many of us dinosaurs there are, but I have old tuners packed-away as well. Seriously, it might be a perfect side-gig for you when you get antsy to do something. Any of us using HE speakers "get" the issues with program material quality as well. Sometimes, I think the end of my travels will be a decent table radio, if only because I don't _expect_ it to be other than a decent table radio.

I know--where are all the old Hams that were around when we grew up? Couldn't hardly throw a rock w/o hitting one of them. Perhaps this means you have an excuse to buy fast gear (cough) I mean to explore an exciting sub-avocation off your sub-avocation after your career Can add-on a DIY Faraday cage and branch out...just messing with you while hoping someone who actually knows something will come along.

Well, this is the web, soooo....my guess is a DIY-guy saw Rebel 3 plans in a magazine or Cohen's book and put a Univ load in it (and tried to "ape" PWK's Shorthorn face/cosmetics). Entirely ready to be declared incorrect by The Historian (or anyone else), though.

No offense intended CB -- Haven't seen altruism twice in one place for so long your post seemed confusing. Please accept my apology.

CB - Just a guess into the vacuum, here, but I think it's the nature of a lot of the regular community here that those interested in the numbers did so long-ago and, through continued and deeper review of PWK's writings (and the refs he cited), have a good-enough handle on this stuff. If it's to better specifically target your amp projects for the community it's clear you have the chops to find a nominal sensitivity target, tack-on increases for distance & headroom, and have what you need. My guess is you've hit the "hrmmph of silence" (aka have you heard of the Symposium on Auditory Perspective...). I might be wrong, but that's how I read it.

"

Yeah it's down to what you want to do. Reflex box is fastest/easiest with solid chances to tune yourself something you like. If that's not the goal but rather to make front loaded horns for them, the biggest things are figuring out how much space your house can tolerate (have a sacrificial closet adjacent, perhaps?) and characterizing the drivers. If you can take 1.5X-2X that reflex box size, you can brew some sort of basshorn that gets you some lower-lows. These ideas are both basically Pats of their time.

For posterity and to save hits off their server:

That's a tough, tough slog, depending on expectations/goals and the resources/skills available. If you're inclined to do it anyway, you'll end-up (for other frequencies) with something else of your own creation as the remaining components have become scarce. It is highly likely that your woofer will not be optimal for the horn design (expectations re-surface, here). That-said, it's not entirely impossible to get something passable, but integrating that bit with the remaining frequencies (and reproducing them in the first place) might be more expensive and demanding than you wish to sign-up for. If you're still out there, what are your thoughts? Oh, and welcome :)