JohnA

You should be able to hear a 1 dB difference, but over a wide range, !like the whole tweeter spectrum, 1 dB will sound more like flavor.

LOL! My early '80s La Scalas clearly have the "potential". But, I rarely listen to them that loud and by the time I confirmed it, I had already had the finished and will not munk that up, now. Ill bet most people are like me and don't push them hard enough.

I used a pair with Heresy HIPs and a Peavey FH-1/Altec 511B-902-8B hybrid. they sound good and rescued the Peaveys from playing below 100 Hz where they distorted a lot. Used them at church coffeehouses.

I think you will want to switch those xovers for Type AL-3 (maybe AL-2, should you ever find any). I eventually detested the sound of the ALs in my set that my brother got.

I would start off with a less intense method, like with that soft cotton cloth and lemon oil for wood, or Murphy's Oil Soap. If nothing else works, try the clothes iron. If you do use steel wool, try to find 0000 and use light pressure.

That's why it sounds like an amplifier problem. Will a McIntosh protection system do that?

Probably. You will hear cymbal strikes and shimmer plus tamborines in the tweeter. Very little voices.

Wasn't it, though! I had a midrange Kenwood tuner and integrated. Climbed on the roof of the dorm and installed an antenna and ran the wire in the window. We could listen to WKDF in Nashville from Cookeville. I awoke in the middle of the night to hear 'KDF announce the Skynyrd plane crash! As WKDA-FM, they broadcast in quad, especially after midnight. Fond memories. No idea what happened to the Kenwood gear.

The larger the diaphragm, the lower the theoretical crossover point. Yet, driver specifics control, so saying a 1" tweeter can be crossed lower, is ..... inaccurate. I recommend you read "Loudspeaker Design Cookbook" by Vance Dickason.

Stuffing (foam, fiber fill) adds "give" to the woofer's back air chamber, making the woofer think the chamber is larger than it is. if the chamber is sized for the woofer, adding stuffing will cause a ripple in the response curve at its lower limit (though you may get a few more Hz deeper response). I wouldn't unless you have calculated a need for the stuffing. My older La Scalas do not have stuffing, nor did my FH-1s with original Peavey woofers.

I've heard the RSW-15 and was impressed, but I'd want 2+. Made the lobby scene in The Matrix feel real. Having started with 1, then 2, then 4 VMPS New Larger Subwoofers, More fill the room and reduce distortion. I feed my 4 with Acurus A250 at about 350 watts each. The "Revenge Of The Fallen" movie cost me 2 subs and another A250!

Properly dialed in, subwoofers should not be obvious. It they are, they are likely 10 dB too loud.

A pair of speakers used as a center would suffer bigly from interference and comb filtering.

These are Min-wax red mahogany over a conditioner and finished with water-based polyurethane. The front edges are a 3/4" x 3/4" cherry strip.

Give it a try. A La Scala is, in fact, a high-quality sealed box system. But the excursion needed to produce 20 Hz will cause a lot of distortion if you push it. 14 dB is 25x more power than the unequalized range. A better choice would be a programmable parametric eq. Set it to about +3 at 60 Hz, +6 at 50 Hz, +10 at 40 Hz and cut off hard below 40 Hz. There is not much music below E1, 41.2 Hz. Though a piano goes down to 27.5.

Paralleling caps works just fine. It is likely cheaper to use one rather than 2, but ya gotta get the values correct.

Maybe. Your 12 ga wire will always be better. The Belden is unremarkable pvc insulated tinned copper. You can make wire with measurable improvements by braiding Teflon insulated CAT5/CAT6 to get a 10 ga equivalent. You might not hear a difference, though. I didn't.

LOL! You can blow up anything.

I use a Meterman 27XT. https://www.tequipment.net/WavetekMeterman27XT.html

A few old Macs has a derived center channel out at preamp level. Does either of yours? If not, Mr. Paul sketched up a line level box to derive the center channel and that could feed your 5100 to control the center. I would link to the Dope From Hope had I found it. I will also recommend you rework the Heresy's crossover to be as much like your La Scala crossovers as possible and drop the taps of the squawker and tweeter on the autoformer one step to flatten the Heresy's response curve. I have done both on my HT center channel Heresy.

Do these chip amps more or less double/halve power then the impedance changes by 2 like a transistor amp? I notice the Toping is rated at 125 watts into 4 ohms.

They appear to be what we have termed Heresy 1.5s. That is, Heresy 1 woofer and tweeter and Heresy II squawker. The caps are original Klipsch. wait until you get your quality electronics back before final judgement, and check each driver to be sure all are working with matching output before replacing the caps. However, they are likely to be the problem. Use high quality film and foil caps for replacement. They will be expensive, but you don't have to spend $200 each. Audiocap PPT The gas at Parts Express ought to do. Go with better if you can. Avoid metalized caps as they sound a little brittle and edgy and Heresies don't need that. Look on the back edge plies for letters and numbers. They will be the serial number and/or the builders stamps. A quick repair for the hole in the woofer is a small piece of cigarette paper on each side of the cone glued with Somers. Smooth the edges of the hole first. you can get a replacement or that one reconed later. I'd just leave the dust cover alone, but there are some tricks with duct tape and vacuums to pull it out.

Heresy IVs are configured for bi-WIRING, not bi-amping. That means 2 pair of wires from one amp channel to each speaker. A dubious benefit if your wires are large enough. Bi-amping, actually for a Heresy, tri-amping, should bypass any passive x-over should be bypassed (short of a capacitor protecting the horn drivers) and then the electronic crossover can contour the driver's response, minimize the overlap between drivers and time align the drivers. This has a verifiable benefit.

Importantly, those '70s receivers have the correct cosmetics to make a 2-channel system look right. Since they sound pretty good, I get both things.

I bought an Alesis RA-150 for the church a few years back. I sounded "rather decent".