JohnA

I don't know if I like SoniCaps or not, but I think you'll be fine with those crossovers. Enjoy¡

A subwoofer cannot be "airy". Since these are horn loaded, the effective radiating area is the area of the mouth, not the driver. But, also since they are horn loaded, the sound is clean. They don't have that subwoofer sound. They're musical and sound "effortless". We listened to (special) AL-5s with the larger 2 and the pairing was excellent. Having the entire bass range horn loaded stood out as clean, detailed and easier to separate instrument sounds. If you need to go with the Medium because of size, I'd suggest buying 2 to get the max output up to where I'd want it. The Medium will cover all musical notes and most LFE effects. I'm leaning toward a Large, but 2 Mediums will fit in my room easier.

I say, yes.

What is the most likely cause for my '70s SS receiver popping/putting with the volume at zero and no input? It started this over the weekend. It was recapped 4 or 5 years ago.

Do you have a recommendation for a cheap tube integrated to replace my '70s receiver to drive my Heresy IVs? Let's say 10 to 25 watts, 2 inputs and tone controls, price in the few hundred $$. I can pick one at random on Amazon, but I'd rather have a recommendation from someone with experience. My only experience with tubes was a pair of Wave-8s.

That's not it. Not even close.

I suppose I'm too late. There is no reason to replace any wiring. It never goes bad and is too short to impact the sound. There is no reason to "rebuild" working drivers; leave them alone. The -Ms are good drivers. The diaphragm for K-55-Ms have not been available for years, though one vendor says he can adapt a K-55-V diaphragm. The original tweeter was a K-77-M *if* the K-55-M is original. K-77-Ms were installed beginning in 1980, maybe late 1979. Since you have Z-brackets, the K-55-M should be OEM. Your best choice for a crossover is an AK-3. A K-55-M easily reaches 6000 Hz, so your 4500 Hz crossover point is unnecessary. You should be interested in matching the horizontal dispersion of the squawker and tweeter at the crossover point. I expect Klipsch made an attempt at that. I've never heard that tweeter, but a pair of K-77-Ms will return your Khorns to the original sound and performance.

Until the Heritage subwoofers are ready, you'll want to look for a large, high output subwoofer to keep cone travel to a minimum. That ought to keep distortion down to tolerable levels. Check Klipsch.com, amazon for sales and contact Paducah Home Theater to see if Cory can help you out (I'll bet yes).

No XLRs, but these are prototypes. Ask for XLRs and you might get them in production.

We were given response curves and they are not capable of reaching the bottom of a K-402, much to the disappointment of one or two men. These things were built to be subwoofers, not small Jubilees.

Neither. The internal design is much different and is built for very low frequencies. The Heritage Jubilee is designed to get up to 800 to 1000 Hz. The Jubilee has a larger mouth and longer bass horn.

The medium will be a fine match. It will go down below any common musical note. You might find it is a little limited in max output compared to La Scala's, but 2 will plenty.

I don't think it's critical. Where can you buy such a thing?

I don't know and Coytee wasn't there for a comparison. I know he has one.

The capability of the X-3/X-5 with a field-coil WE-555 treble unit was quite the surprise. We have better, now, but late-40s audio was in fact good. It was good to be a Fairchild! I'd guess from 100 to 6000 Hz, we don't have better, but Mr. Paul worked on the extremes until the Mighty Klipschorn became and it's still with us. I enjoyed it like seeing an old Packard or Ford still on the road!

Roy used a Tool (!!??!! 😱) track in the demo. It was complex, crowded and toolish. All of the subs did a fine job of separating plucks, kicks, thumps and whacks. The system really stood out when the La Scalas slid in as all the bass was horn loaded. They do not sound like subwoofers, none of them. You can almost always tell there is a DR subwoofer in a system by "that sound" what ever it is. These guys have balls!

I had a pair of La Scalas with -M/AL networks for rear channels. My brother has them, now. My fronts came to me mismatched, 1981 -V/AA and 1982 -M/AL. As luck would have it the first squawker I found was a -V and the odd one was reconfigured to 1981 spec. The -M/AL pair had a howling resonance in the lower registers of a French horn and I HATED them. My brother or I converted them the -V/AA, neither of us can remember which. I think the contouring in the Type AL was to blame and the AK/AB/AL was pretty quickly replaced with -2 versions. That pair were 1985-ish vintage and had the later round magnet woofers. The T-S are different from the square magnet woofer, I recommend AL-3s with those because the howl was near the crossover to the K-400 and the AL-3 has similarities, but is simpler than an AL.

There are a number of possibilities. Beginning with Cambridge is good kit. The D-to-A conversion and filtering out of errors is done with pretty inexpensive chips and both DACs could well have the same, or equally performing chips (my guess). There is no correlation between cost and performance in High-end Audio. Some brands set price so you'll think they are more worthy. See Wilson Audio WAMM at $685,000.

Travis, I hope you've recovered. We missed you. Actually they called them Small, Medium, Large and XL, aka "big boy" by Jesse, on the graphs.

You should see what Roy uses to demo Jubilees!

LOL! Somebody's google-fu is a failure.

There should be no need for a "rebuild". If a driver is not working it can be repaired. Test by putting you ear close to each driver to see if it's producing sound. You can test DC resistance or continuity with a volt meter. A good volt meter can detect AC voltage applied to the driver terminals to test the network, if a driver tests good, but is not playing. That same good meter can test the network components, *IF* you can disconnect enough to test it alone. Finally, if they sound recessed, laid back or "polite", consider replacing the capacitors with high quality film and foil caps as they may have gone off spec enough to affect the sound.

Aside from pretty obvious terminal strip corrosion and other visible issues with the network, I'd recommend looking for very late K-77-Fs that have a recessed flange so the mouth of the tweeter is made flush with the motorboard. That cured some grittiness my La Scalas had. PM me for more ideas.

The size, of the 4, should be selected by output and performance. There is not a recommended La Scala match, but I'll pick Large. You will not want or need additional subwoofers for any reason. If I were you, I'd replace any direct radiator subwoofers you have with these. They are easily special effects capable. You will not regret it! We were given impressive response curves and told a lot about the physics of the subs, that i won't discuss. The Medium goes deep enough for any music, the Large should cover most LFE effects, if not all and the XL is likely brown note capable. 😆 Choose the additional subs for the max dB output you require. They are powered, so you will not need an additional amp. The amplifier power is surprisingly low and the embedded amp allows some control of distortion. We were not given a release date, but speculation was not before Spring/Summer '24. You have plenty of time to try to time the Market. This is the Large.

Serial numbers are fine. Names, SSNs and DL numbers are not, now that internet based ID fraud is rampant. (I hope VISA and grubhub go broke; they don't even try to prosecute.) Your serial number is 17N159, the 16,159th Heresy made. The wood is birch and the butt joints say they left the factory raw. the "Type" was most like HD-BR and a previous owner stained them. Walnut?