WMcD

Condolences to you and your family.

https://community.klipsch.com/index.php?/topic/196075-k-401-horns/ That link has more info on building. One "issue" arises from the use of flat ply for the top and bottom walls. The expansion area can mimic that of the K-400, which is good. But the shape of the side wills is not the same as the K-400. Therefore I suspect the directional pattern will not be the same. Maybe close enough but worth pointing out. Further, the K-400 has a smooth transition in cross-section from rectangular at the mouth to round at the throat. Perhaps a small issue. WMcD

Diz has better reading comprehension than I. So you want plans to buid a box?

You really should do a bit of research and consideration of your skills. * The 811 has a recommened cross-over of 800 Hz. * K-horn struggles to get up to 400 Hz. Speakerlab plans are reportedly accurate but difficult to cut accurately. Sealing the back with ply can make it closer to recent K-Horn * Jubilee (needs two 12") are much easier to cut (and most parts are the same height). Probably good to 800 Hz. Back is built in. * LaScala easiest to build but only goes down to 60 Hz. Maybe okay for a garage if that is what you mean. * Consider slightly bigger Peavy W box or "Eliminator" boxes too. * Someplace there is an EV tractrix bass bin. * People have MWM bass bins but they are large. Look at the AES article comparing K-Horn and Jubes. There is video of the factory showing how LS are now built with the dog house preassembled. It uses 1" MDF so side walls don't vibrate (pobably 3/4 inch with some bracing will do well)

Randy that a great insight. Nice work. Of course Pro-Media is a subset of what you're suggesting and would fit the issue about a "subwoofer."

FWIW: The speakers don't create static or hiss or any other sounds. They just respond to what the amplifier feeds them. OTOH, Klipsch speakers are very efficient/sensitive and will reproduce what the amp sends them moreso than other speakers. Therefore if an amp is noisy you will hear it "better" on Klipsch speakers. Please give us a model number for the speakers. And it would be interesting to know more about your amp, too. Have you used the amp and other parts of the system (CD or video or cable) for long? These components can produce noise. If you switch around the input selector you might be able to identify the source of the noise. Also processor setting such as Dolby Theater One experience of mine from long ago was that the processor in receiver produced an annoying amount of noise ubt it was not as mercurial as you report. Generally, nois is a high frequency event and so subwoofers are not going to reproduce it. It'll take some experimentation to hunt it down. WMcD

I believe this is pretty normal. Part is based on m,y building a piece from The Bartley Collenction, Now out of business. You also should hunt around the internet. Cherry is like a lot of hardwood in that in a raw state as sawed, the wood is pretty much beigh (light tan). As it is exposed to the atmosphere it changes toward a rust color over, say, three years, by oxidation. Apparently this is not prevented by a "clear"cover of varnish or shellac. Though these covers always incease contrast and darken the wood somewhat. One problem for sellers of the solid wood or veneers is that buyers want that rust color in the wood as sold. The solution is that they will force the process by applying a lye solution or by applying a dye or stain. The bottom line to the analysis is that cherry will tend toward rust but what you buy is probly a somewhat dyed beigh cherry which changes toward rust even moreso. WMcD

I had to check Walgreens' site for five days and then got appointmments for Pfizer first and second. The first was just last Thursday at one of the few Wags in the Loop which was still open. The second will be in four weeks up north of Wrigley Field. No reaction --- but I'm pretty sure I had Covid a year ago at the end of January which might have been a factor. I asked for and got it in the left arm figuring that if there were a reaction it would be better to have it in the non-dominant arm/hand. YMMV. WMcD

Good idea. When a ham passes away his name is followed by "(SK)" for "silent key" Maybe we could use SH for silent horn. WMcD

Disturbing.

I just looked around the Internet and see that the MC2105 has a damping factor of 13. I don't see any info on what tap was used or what load was assumed. Assuming an 8 ohm load this equates to an output impedance of 0.62 ohms. = 8/13. This does not mean that you should put a load on it of 0.62 ohms. In conclusion though, if you have a speaker which varies between 4 ohms and up, you should use the 4 ohm tap.

Here is a graph of the Cornwall input electrical impedance. Putting a single value on the impedance is not possible because it varies with frequency. This is from the Belgian Audio Society test and I suspect it is on what we know as a "Cornwall" rather than a Cornwall II. I have not seen any factory equivalent. It is important that this goes down very low and probably to 4 ohms. The Heyser review of the Klipschorn is at least consistent. And likely the K-33 has a voice coil resistance of 3.8 ohms or so. Klipsch's notation that their speakers are "8 ohm compatible" seems to only be saying that the owner can hook them up to an amp which says it is fit for 8 ohm loads. Very generally the output impedance of a transistor is lower than 1 ohm despite what the autotransformer taps say. This is not widely stated by manufacturers but at least in some instances the damping factor is given and ouput impedance can be calculated from this. Also, it is true that Jacobi's lww is good in some circumstances but IMHO it is at best difficult to apply here. For exaple, if your amp does have a 0.1 ohm output impedance we'd be looking for 0.1 ohm speakers. One this which is generally recognized is that audio amps put out less distortion when driving a load which is high in impedance. Distortion is lower when you attach an 8 ohm load to a 4 ohm tap. Another matter is that background hum and noise is lower in magnitude when the transformer is not stepping up their level by the use of e.g. the 16 ohm tap. WMcD

There was a story of PWK giving a demo with Heresy's placed in front of KHorns with no announcement of which would be playing. He'd start the demo Isecretly playing only the Heresy's which everyone (?) thought sounded very good. Then he'd say, "Oh, let's hear the KHorns (alone)" which everone thought sounded very good and a bit better -- but surprizingly not startling so. What program was used I don't know.

Do the speaker boxes have serial number / model number labels on the back and can you take photos. That info might provide some background. Bacek has a good guess IMHO. Wouldn't it be something if they are different models.

Just to continue my earlier, if overly long post . . . The "ramps also have a sharp angle which is difficult to cut. So I just used a less steep angle on that end of the ramp and use a 1/4 round piece of trim. A 3/4 x 3/4 piece would do as well. I also did use "reflectors" as shown in the Peavy. I don't think they reflect but should even out the cross section a bit going round the bend. Let me again suggest the form factor of the LSII. This is because the bass bin is about a 2' cube. But importantly, all the vertically oriented elements should stand between the upper and lower square plates. Therefore it is important that they all be the same length (height) but an identical error is not of consequence. You can rip a 4' x 8' and make sure the cut is arallel to the edge but not really worry about the kerf. WMcD

I don't quite understand. You say the project "demands" maple gray. But then it seems like you may want to change the color. From what I see on the internet the maple is bleached and then dyed gray. When you say "finish" are you talking about the somewhat clear varnish or lacquer that goes on top of a dyed or stained piece of wood. Most will acentuate the grain or pattern in the wood. What is the goal? For that matter, what are you starting with. WMcD

You should use the search function on the forum to find LaScala plans. You'll see the option to search for content with all words rather than any word. You'll see several plans and it is worth taking a look at all available . Among the results is my post with the plans by HDBR. I can vouch they are absolutely accurate to the extent I used the info to make full size drawings. I suggest you do the same. I know grid paper of that size is expensive. Let me point out that some Christmas wrap has a 1" x 1" grid on the back. Hallmark? There is video someplace (someone will help, please) showing the factory construntion of an LSII. It is make of 1" MDF. If you like the separate "top-hat you figure that out easily. Also, you'll note the dog-house (shaped like that and the woofer lives there!!!) is built up separately with "home plate shaped elements at the top and bottom and the assembly is slided into the cubic box. Otherwise it is a bear to get everything lined up. Let me suggest you don't try to make the sharply poiinted front of the doghouse because that cut is very diffiult. Rather, replace it with a 1.5 inch wide board similar to the Belle. I would not use MDF in the weather though if painted with boat paint everywhere on normal 3/4" ply you might be okay without marine plywood which is expensive. There is the theory that the sides resonate and at least some builders put a brace between the wall of the doghouse and the wall of the cubic box. 1.5" wide should do. Of course critters will love to build a nest in them and you should consider metal screening as necessary. Those braces could be put to use in this aspect. WMcD

You are asking about "velocity factor." https://en.wikipedia.org/wiki/Velocity_factor WMcD

I'm glad that worked for you. I've been looking for some diabolically evil project to which to apply this phenomenon. MMMmmm. Haven't found one. Smile. WMcD

I'm pretty much with Randy. There was a writer for a big automobile magazine long ago. He wrote that people ask him (he being an 'expert') what car they should buy. He said he tells them Honda. He explained that this was because with a Honda the person would least likely to come back and say they're unhappy even though it even though there might be better cars for their specific, and unpredicatble, situation and price point. You can't go wrong with a CW variation. If you can find them on the used market, the Forte II, Quartet, and Chorus II are magnificent. Good bass with the passive raditor and the terrific tractrix midrange horn. WMcD A

Ha. IIRC there was an article in QST long ago describing corillaries to Edsel Murphy's laws. It was that units of measures given will always be in something odd. Velocity will be in furlongs per fortnight. I very much appreciate you bringing it to mind. WMcD

Good to see you Larry C.

Be careful. I suspect the HIII has a second order crossover for the woofer. If so, when you remove the connection to the woofer the crossover will form a series LC circuit to ground (i.e. across the input terminal). This will create a short circuit at about the crossover frequency. Damage to the L and C is certainly possible. I think of this tip from a moderator here long ago. Independent of that, I read about a train wreck in a non-Klipsch unit pro unit where a bass driver was found blown, the cross over was found foblown, and the amp was found blown. I suspect what happened was that the woofer was driven to destruction and was an open circuit and this caused the LC short. Then it was a race between whether the crossover components burned out from taking all that currect, or the amp was blown from the effective short circuit. (I suppose the coil could overheat causing a fire though I'm not sure.) Maybe someone can give advice on electrically disconnecting the LC, I suppose you could replace the woofer connection with a dummy load resistor of appropriate rating. However, that could heat up and cause a fire in the box. "Let's be careful out there." per Sgt. Phil Esterhaus WMcD

Yes. Any anomoly is potentially dangerous. Have a licensed electrician take a look at it. WMcD

I believe there was a Cornwall which was meant to be situated landscape or portrate. Neither the mid nor the tweeter were at the midline. Also there is something with a K-1000 midrange. Eventually it was superceded with what was initially called a Cornwall II. This had the K-600 mid like you see, the woofer, mid and tweeter were at the midline and it was presented as a portrate orientation speaker. Woofer near the floor. Eventually the "II" got dropped. This is probably why you see II on the spec sheet. But then there was a switch to plastic tweeter and mid and that was called the Cornwall II. Woofer moved up. The above might have so errors but close. WMcD