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One small footnote...the dashes on the left side of old cap indicate which lead is connected to the outer foil, and therefore that lead should be connected to ground (or the point closest to ground) in the circuit. That gives a slight bit of shielding in RF circuits, but I rather doubt it means anything at audio frequencies.

Stereo power amps usually have a great deal of seperation, above 60 dB in most cases. The limiting factor for seperation in an all-analog chain is usually the phono cart, which will usually have no better than 18 dB seperation at the extreme ends of the audible spectrum. In the middle 25-35 dB is the norm. FM tuners will usually do about that well or somewhat better, but the seperation of all but the best designs poops out as the 30 Hz and 15KHz cut-offs are approached. After all is said & done, if your entire chain has at least 24 dB seperation across most of the audible band you're doing fine.

Talk about doing things the hard way...a better approach would be to cut the slices slightly oversize and fill in the "steps" with plaster or putty. Use a sheet metal tool of the correct profile to smooth down the surface and there you go. Also, many DIYers don't realize how many computer numerically controlled (CNC) milling machines there are out there. If the set up fee is not too high, each slice could be cut exactly the first time. Most CNC machines do not have the reach to make the entire depth of a midrange horn in one pass, but it should be possible to cut the number of slices in half.

Digital to Analog Converter, as in, taking the bitstream from a CD and converting it to a signal to be amplified and sent on to the receiver and then to the speakers.

If the gap is small (say 1/16th inch or less) and you can force or clamp the pieces into line, I would use Titebond II, a yellow outdoor glue. It is nearly as strong as Gorilla and much cheaper. It also is easy to clean up with water and won't stain your hands. Liquid Nails is not appropraite for cabinet repair. It is really designed for construction and joints that will never be disturbed. It dries very thick and can't be coaxed into joints like the thin liquid glues can.

---------------- On 1/14/2005 10:03:45 AM Daddy Dee wrote: Heard this interesting story on talk radio this morning: First instance of "stereo" was developed by Magnachord for GM to help with analysis of engine noise. Anyone heard this before? Is it so? ---------------- Squawk radio rarely knows what its squawking about, and this is no exception. If you mean the 'concept' of two (or more) channels of electrically transmitted sound, that goes back to the 1890s-1900 timeframe when telephone transmitters were installed in the footlights of the Paris opera, and persons some miles away could hold one or two receivers to their ears to listen. If you mean stereo as in electrically transmitted and reproduced high fidelity music, that is yet another Bell Labs project from the 1930s, which made a profound impact on PWKs three-channel wide-stage stereo concept. In parallel, Blumlein in Britain was researching two channel recording, and in cooperation with London records, made a few stereo recordings in the 1930s. I think it was he who devised the two channel record groove system. This is not to say that GM didn't have multichannel audio for research, but if they did it was for a dedicated need and was not in the main stream of two-channel sound, which can be traced through Bell labs, Blumlein, CBS and other major players. Magnecord was an early maker of magnetic tape machines and used the technology brought back from captured German recorders from WW II. I think PWK had a Magnecord at one time.

---------------- On 1/8/2005 7:37:58 PM colterphoto1 wrote: Check the specs, my guess is that the MCM 1900, being engineered as a PA stack, would be much beamier than a LaScala. I used to use these for PA, they were AWEWOME. We had the entire stack I think it was dual 15's in the W bins, a 10 straight firing into a low-mid horn, dual driviers on a high horn, then an array of what looked like K-77's on top. Michael ---------------- That array was five 2 x 5 inch piezos made by Motorola in a concave arrangement. Paul told me later that the response of a piezo narrows when over-driven. I think that is one of the reasons (beside ignorance about using crossovers with piezos)why piezos got a bad rap when first introduced. Michael you know this already-Lemme also point out that PA speakers _produce_ the sound, and therefore are part of the instruments (gutars, drums, keyboards, sequencers, ad infinitum). OTOH, home speakers _REproduce_ the music. That distinction is why so many people are disappointed in trying use PA speakers at home. The ends each type serves are different, not to mention the environment. Maybe in Heaven I can have the Dead's old Wall of Sound as my personal stereo. Here on Earth, it doesn't make much sense.

I'll jump in. The CW IIs-I also have an 86 pair so welcome to the club-either have some kind of caulk around the woofers or the gaskets are really stuck to the baffle. Unless the woofers go bad, don't try to take them out. There are plenty of pictures in this forum of what the Cornwall Ones look like inside. The Cornwall Twos (and perhaps some of the later Ones) have extra bracing inside to cure some resonance problems. And yes, there is no damping inside. The design was optimized without it. http://www.belgaudio.com/kcmap.htm This is a test report on a pair of 86s and is one of the most complete independant reports done on any Heritage model. It has several pix of the inside to satisfy our curiosity.

For speaker wire, get yourself a spool of 14 gage low-voltage outdoor lighting wire. Cheap, very durable, and large enough do runs up to 50 feet.

An Associates degree in Electronics Technology is a good starting place. If you have any prior social science electives you can get in as little as 18 mo. That education will also help you filter out a lot of the BS that circulates in the audiophile world.

Copyrights and trademarks are very different things. Titles (of books, films etc) cannot be copyrighted. So Bradbury's whining about Farenheit 911 was entirely personal, he had no legal recourse strictly on the basis of the similiar name. I have a registered copyright on a certain chunk of text with a title attached. I have rights as far as the text goes, but the title is fair game. When I register that as a trademark (or servicemark) it's a different ballgame insofar as goods and services (as opposed to intellectual property).

Howz about a diagram of how the horn is configured? Beautiful finish

Besides Klipsch, I don't have much brand loyalty because the brand names don't mean much anymore. The mass of consumer durable goods in the US are made off shore and branded by the current owners of the name. This doesn't mean they are necessarily worse than Made in USA products (if you can find any) but most goods are dredged up from third-world factories as generic products, slightly customized and then 'branded' for each countrie's preferences. I drive a Mercury Grand Marquis-an American car, right? Nope, made in Canada. My old car (an 89 Grand Marq also made in Ontario) had a Blaupunkt stereo-made in Germany? Nope, Indonesia. RCA is owned by Thompson-CSF, a French firm, and Zenith by Lucky Goldstar. Even brands that are still-self owned have, in many cases, sacrificed build quality to be 'competetive' in the global economy.

---------------- On 1/3/2005 12:13:59 PM ct1615 wrote: What is the difference between a silk dome tweeter and aluminum dome tweeter? Why did the synergy series switch between the two? ---------------- Sorry this took so long... First off I can't answer why the Synergy changed its tweeter, you'd have to ask Klipsch. This part of the answer applies to domes used as direct radiators: Generically, there are two primary differences between any fabric dome and any metal dome. The first is how the dome resonance is managed. With a fabric dome, the resonance is apt to be below the operating range of the tweeter. With a metal dome, the resonance is apt to be at the top end of the range or slightly above. In certain cases this resonance is very audible and is referred to as 'oil can resonance'-not a good thing. Some people feel that even a supersonic resonance is fatiguing to listen to. The second difference is the break-up modes of the dome. A softer dome has less rigidity and therefore has a less linear response to an input signal, but a soft dome also damps out faster and has less 'hangover' than a metal dome. A metal dome will respond in a more linear fashion, but the resonance problem means it will usually have a 'hangover' effect as the sound waves propogate quickly through the dome and reflect from the edge of suspension and back again. For direct radiators, most companies have gone to silk or other fabric domes. A few are now using laminated domes, with metal and fabric, to try to get the advantages of both approaches. For horn drivers: The distinctions are not as clear. Remember that a horn offers a high air impedence at the throat and therefore exerts a powerful constraint on the diaphram. Most horn drivers using fabric use linen covered with varnish. Due to the constraint of the horn air load, plus a suspension resonating higher than a comparable direct radiator, these diaphrams are moving tiny amounts for the same SPL as compared to direct radiators. The resonance of metal horn diaphrams is usually not an issue because phase irregularities in the throat and internal horn reflections will usually kill frequencies near a metal diaphram's resonance. Very few horn tweeters go above 17 KHz so if the metal dipahram is resonating at, say, 22 KHz it will not be an issue. Bob Crites recently posted a series of curves for fabric, polymer and titanium diaphrams on a Klipsch high frequency horn. The titanium was the best, and I don't think diaphram resonance was an issue at all.

My advice is, don't try at all. Pulp paper cones like the K33 absorb the stains all the way through and they are now part of the cone forever. You may well do more harm than good introducing more liquid.

I have a Zenith AM-FM table radio from 1960, although the circuit design is the same as models from at least 1951 onwards. The audio output is a 35ZGT operating single-ended. (I may have blown the exact number, but it is a 35 series tube) I think a pentode. This was very common since most of these sets were "series heater string" designs that had no power transformer. The heaters of all the tubes were in series, and the voltage drops equal 110 volts, more or less. My Zenith heater string only equals 102 volts, but I'm sure that the selenium rectifier's drop and other losses mean that no heater is overstressed. I think these used a siimple voltage doubler to get B plus which would be no higher than 240-250 volts for these tubes anyway. Trust me, the single-ended approach for these and competetive radios had nothing to do with fidelity, it was all about reducing the parts count and keeping to target cost.

Look at Paul's first paper and his patent. These will give you all the influences. Horn folding was devised sometime in the Roman era to make brass instruments managable in size, and when sound recording came along in the 1870s, gramophone designers took their cue from that concept. One influence that may not be readily apparent is Voight, who also had a corner horn in the 30s. The lowdown on that is in Bruce Edgar's interview with Voight in Speaker Builder in the early 80s.

I have 86 CW IIs. I have heard the CW Is over the years, but not done a side by side test. My opinion is that the K-79 used in the CW II is simply a better tweeter than the K-77, smoother and more extended. It also seems to have a slightly broader pattern than the K-77 as used in the CWI, and it doesn't spear the ear as much. It's much harder to compare the midrange. Not much is known about the K-52 mid driver of the CW II, except that it was orginally a Heppner design, not part of the Atlas or EV lines in the family tree of the K-55s. The K-55s have been scrutinized every which-a-way since they are much more numerous. The K-52 seems to have been used in a smaller range of models so less is known. Another thing, and I am not positive on this, I think the CW IIs used a steeper cutoff between drivers, doing a better job of keeping the bass out of the midrange and the mid out of the treble. My bottom line is that I love my CW IIs and want another pair for the back channels of my 5.1 set-up.

The autotransformer is, I believe, an iron core. You cannot get the same autotransformer action in an air-core design as an iron one without having a massive, and I mean massive, tapped air core coil. If it's "iron core' distortion you're concerned with, don't be. The autotransformers used in Klipsch Heritage will not saturate with any amount of power you could stand to listen to.

http://www.lileks.com/ James Lileks-blog and retro stuff http://www.perfessorbill.com/index1.html Bill Edwards, Master O'The 88s http://www.archive.org/movies/prelinger.php Prelinger Archives of old films-classroom, educational, industrial, advertising

Your profile says you're in LA, is that as in Los Angeles or Louisiana?

Klipsch used motor-run paper in oil caps, which are designed for continous duty, as opposed to motor-start caps, which are for just that purpose. Back in the day,there was nothing better than paper caps for crossovers and the motor-run types were (and are) stable and rugged. I don't want to get into the whole Capacitor of The Month issue, which has gotten me entirely too upset over the years. To judge by the online chatter and most (but not all) press reviews, there seems to be a direct correlation between amount of money paid for capacitors or any audio component and the perceived sound quality. That is about the only accepted "correlation" as audio tweakery goes further and further away from science into metaphysics.

Size, sensitivity and bandwidth need to be specified before one can say "better" than the Khorns (or anything else). From the looks of your webpage, I'd say you already have the optimum bass set-up possible at home

"Tube Research Labs typically does not publish traditional measurements on its equipment's performance. These measurements illustrate how machines hear, not how humans hear. We probably are years away from having measurements which we can really associate to or correlate with the listenability of a device." meanwhile, trust us and fork over the kilobucks..right....

The 'original' Klipschorn top end was the K-5 which was, I think, plywood until it was replaced by the K-400 in the mid-60s. The current thread on Shorthorns and early Cornwalls shows systems with metal K-1000 (Hz) horns. My question is, why the gap between the 500 Hz (I think) K-5 and the K-1000? I know dies for casting metal horns aren't cheap, but a smaller horn, with, say, a 600 Hz cut-off could have been made of plywood using the same techniques as the K-5. Considering that Klipsch was using the University SAHF driver on the K-5 and K-1000, a new plywood horn would not have cost that much to implement.