Stu Pidass

I have a K-77-M driver in my Cornwall that emits an "crackle" but only on an internittant basis. I blamed it on my old amp for years, which has analog controls, because that sound coincided with changing the volume and or adjusting the left right balance. I have since had the amp services (cleaned and contacts de-oxidized) but the crackle still remain in one speaker even at fairly low volumes. I took the back off and removed the driver thinking the diaphram needed replacement. The four screws removed from the driver wothout problem (pretty simple stuff). That's where I was stumped. I expected the tweeter to somply come apart. Uh Uh. I had to apply some force (prying with a screw driver)and the horn part detached from the middle. I was alarmed by a cracking sound as this happened and thought I broke the damn thing. There appeared to be a small amount of what looked like dried glue attaching the "horn part to the rest of the driver which had now let go. So now I have the driver in half and I can't see anything that might need replacement. I removed a paper gasket and followed by a metal screen but still really nothing to speak of that resembled what a diaphram might be. I then pryed the magnet from the middle part of the driver. Again there was a dome shaped "thing" that appeared to be in perfect condition. I pu th ewhole thing back together, reasembeled the speaker and played a test album. The crackle had completely dissappeared. The next day, however, it was back and seemed worse than ever. How do I rid this? What is the diaphram. Should I replace te diaphrams in both speakers? If so, how? Or should I consider the more expensive option of replacing the entire driver (or both)? Any advise please.

Believe me, the wait will be insignificant once you hear these beauties. Their legend is well deserved. ENJOY.

As a long-time Cornwall owner I trust you'll enjoy these beauties for many many years. You might be interested in the post entitled "Cornwall Tweeks" in this same forum. Some excellant suggestions regarding speaker placement and free or cheap tweeks.

I believe you are correct. Cornwalls had ther midrange and tweeters mounted from the inside of the cabinet. Also the midrange of Cornwalls are metal while Cornwall 11's are made of plastic. They should be fairly easy to distinguish.

Dr. Dave: It's my understanding your Cornwalls are manufactured in 1982. The alpha character in the serial number denotes the year of manufacture and is as follows: 1962 A 1963 B 1964 C 1965 D 1966 E 1967 F 1968 G 1969 H 1970 I 1971 J 1972 K 1973 L 1974 M 1975 N 1976 P 1977 R 1978 S 1979 T 1980 U 1981 W 1982 X 1983 Y You will note that the letter V was not used and therefore I suspect it to be an X ('82) or a Y ('83). After 1983 usually the first two numbers of the serial number represent the year produced. Not sure of their value. I paid $1750 Canadian for new ones back in 1981. They are Not nor will they EVER be for sale.