JohnA

DIY. https://www.woofertester.com/wt2product.htm https://www.parts-express.com/Dayton-Audio-DATS-V3-Computer-Based-Audio-Component-Test-System-390-807

K-77-Ms don't need the diaphragms replaced. They came with the ribbon lead diaphragm that carries the higher rating. Perhaps they were not -Fs, but the K-77-? I saw in the Lab would have fit my '81 LS. The flange perhaps pushed the mounting screws wider, but wasn't definite.

No. However, a good 2-channel amp/receiver will have a power supply with much greater reserve power capacity than your AVR. The old Tanks of the 70's had to meet the FTC power rating procedure so the bits and parts were sized to handle more heat and the the PS was robust. The old amps mostly had low Damping Factors and tended to sound soft similar to a tube amp. I like the sound of modern amps with large DF better (crisper and with tighter bass). To get both I went with all separates. My power amps take a long time to go quiet when the power is turned off, demonstrating the depth of the energy reserves. All that comes at a price, though.

No. But it should be no worse than motor oil. You wouldn't lick that off your fingers.

Not true. PCB is used in high voltage xfmrs and the like to retard fire and heat breakdown; it is nearly inert and almost will not breakdown. It is difficult to get it to burn in a coal-fired furnace at 3000F. It was not used in the motor caps Klipsch put in the Type AA. I doubt the older boxy caps used in the Type A had it either. It's pretty expensive stuff. https://www.tedss.com/2020005873 But a leak means replacement is needed. The oil conducts heat and improves the insulation of the dielectric.

Not all of the old xovers I've had needed to be recapped. I'm sure the AAs do sound better than the As. The tweeter section adds needed EQ and attenuation to the K-77. In a home setting, the -M tweeter should not need the zener diodes. If you still have original K-77 tweeters, I'd reconnect them until you can install the -Ms ribbon lead diaphragms. The K-77 is rated at 2 watts continuous/20 watts peak. The -M is rated at 5 continuous/50 peak. Change the diaphragm and you'll get the higher rating. Better yet, Try to find a pair of K-77-Fs(?) that flush mount the tweeter mouth to the front of the cabinet. or send me a PM.

I use Audacious and an OLD version of RealPlayer. Ver 10, I think. No ads.

Trouble is, no one abides by those rules and the "government" is not allowed to intervene by the First Amendment; not that the Constitution has meant anything to the government in the last 21 years.

Become a backwater and die like broadcast TV.

I can't tell if I posted in this thread, or not. It's grown too long. I was both surprised and disappointed at the lean/bright sound of my new H IVs when I got them. Not at all what I remembered from hearing them in Hope. So I set about "exercising" the woofers with Dub-step while the Loudness was on and the bass at max for this old receiver. That way I could pump the woofers and not be annoyed with the door shut. At 48 hours, there was a marked difference (more bass,more natural sound). After 4 days, they didn't seem to change much. Now I don't use a subwoofer with them at all. Just looked. It's unplugged. I must admit to their break-in and with chagrin that I have stated many times break-in was a myth. I don't remember my old Marantz and Boston A150 speakers changing that way. That was so long ago, maybe they were floor demos.

LOL! I simplified. Down to only 5.0.4 and only 2 Heresy IVs in my computer room.

I would say something similar, but it didn't take me that long to notice a resonance/howl in the common range of a French Horn that I found very annoying when listening to 1986 AL La Scalas in the same room with '81 AA La Scalas. My brother has the ALs, now. 😁

La Scalas from 1985, would have many mods to properly use AL5 crossovers. Please do post pics!

It is not my intention to start a kerfuffle, but, .... Now that things and time has passed, is there any possibility of examining the records that NMSU posses and perhaps copying some? It is a shame there is animus between groups that both want to preserve the legacy of Mr. Paul and do it honestly. Could another party mediate? Perhaps an explanation of the issue, depersonalized, would help.

Some Pro "subwoofers" have high pass filters. The box tends to limit the LF excursion well enough, but at only 6 dB/octave. Most music had very little energy below the 41 Hz low E of a bass, further limiting the need for a woofer high pass filter.

I'd say almost all. I would not choose them over my old La Scalas, never mind K-horns of Jubilees. I have found them boomy with recessed vocals and pretty hot somewhere around 4k. Certainly no more low bass output than a La Scala. Mr. Paul compared the frequency response of the La Scala to a "well known theater speaker" in a paper published on the "new" La Scala. I have always suspected it was the A7 and it falls well short. I used the A7's horn and driver in a home-made system similar to my La Scalas. That treble horn/driver has some nice attributes and it's smooth sounding, but lacks the shimmer the K-77-M gives.

Several Heritage parts, at least one Jubilee. https://www.estatesales.net/SC/Woodruff/29388/3395955/127591818

I read an paper discussing foam around the mouth of audio horns to absorb reflections/diffractions. Since many foams are short lived and too thick, I used 3/4" felt. Clean and easy and it's been there since 2000 or so. Other things made more audible difference, but I'm still a little subject to audiophoolery. 🙃

The very opposite is true. People run Cornwalls with 2 watt tube amps. You have a room placement issue. They should be at least against the wall and as least as far apart as the listener is back from them. There could be other issues with the room, too. Cornwalls do not lack bass unless a woofer failed. Check and turn off all EQ in the receiver and set the speaker size to "Large". Set the receiver to "No Subwoofer" and 2 channel only until you add other speakers. If there is an adjustment, set the speaker impedance setting to 4 ohms so the amp will deliver the current the 4 ohm woofer needs. Listen a while before changing the caps to be sure they need them. Do not use cheap caps; each one should be a film and foil cap and you should expect to spend $70 each, or more, to provide the quality the speaker deserves. Metalized foil caps will sound gritty. I will recommend lining the openings for the squawker and tweeter with heavy felt to absorb reflections off that edge. Perhaps unneeded, but lining the woofer opening won't hurt. Unless your F-I-L intends to so with surround sound, a stereo receiver would be a better, and simpler, choice.

I did not want to modify my H-700s, so I bought these and finished them with polyurethane. The worked very well. https://www.madisoundspeakerstore.com/full-range-speaker-kits/fostex-bk-16-angle-stand-each/

I've been using braided CAT5E for speaker cable for 22 years(!). Must be wore out by now, what with knocking electrons out of their orbits for that many years! 😁 I am currently listening to a Technics SA-300 from '79 that I had recapped. That's probably all yours needs. The SA-200 I bought in college is in the garage driving a pair of Auratone 5CTVs.

LOL! Speed density EFI could also adapt using the O2 sensor and Intake Air Temp sensor, so it was not so dire as that. Add in that the WOT A/F ratio was 12 to 12.5:1 and the best power mixture is almost always 13.2:1, a *little* leaning is a good thing. BTDT with mt '87 Mustang GT. I measured EGTs on each bank to get an independent (cheap) look at WOT leanness. Off topic, so I'll also say, it's still a Mustang.... And I have decided metalized polypropylene caps sound subtly gritty. 😉

You can parallel resistors to raise the wattage limit. The resistance will have to be higher to use them in parallel.

Most likely a function of wave length vs. riser height and marketing/speaker design.

In general, if you can hear the sub, it's 10dB too loud. At +5 dB, my system sounds "impressive" without the subs being obnoxious. You really ought to get a sound meter to accurately setup the sub(s).