k-77 vr,s k77m q,s

[mr lascala]

HI GENTLEMEN, IS THE K77 ROUND MAG BETTER THAN THE K77M SQUARE MAG WHICH ONE SOUNDS BETTER SOME SAY THE K-77M IS BETTER I WOULD LIKE TO KNOW WHICH ONE WOULD BE BETTER IN MY 78 LASCALA,S .IS THE K77M A CHANGE UP TWEETER OR AN UP GRADE INFO WOULD BE APPRECIATED. CAN I STILL USE MY TYPE AA CROSS OVER ON THE K77M.

[BEC]

Your 78 Lascalas would have the K-77 (alnico round magnets). I have a pair of 77 Lascalas with those in them. The K-77M came along later when alnico became hard to get and has the square (ceramic) magnet. Someone has listed a spec on this board before that indicates that the K-77M has a bit more output for a given input than the K-77. I listen to both types connected to the same Lascala several times a week (testing the ones I have rebuilt for people) and I really can not tell which type is playing without looking. They sound exactly the same to me.

Bob

[mr lascala]

HI BOB, I HAVE LISTENED TO BOTH & THE K-77 M SEEMS TO BE SHARPER THAN THE K77 OR IS IT JUST ME, THE REASON I WANT TO KNOW WHICH WOULD BE BETTER I WILL PUT THE TWEETERS IN MY OTHER SPEAKERS & SELL THEM KEEPING THE LASCALA,S

.

[BEC]

Kim,

Some on this forum prefer one of the tweeters above the other. Probably if you took a poll you would find almost as many prefer K-77 as K-77M. I have two sets of Lascalas, the ones from 1977 have the K-77 and the ones from 1994 have the K-77Ms. Although the two sets sound slightly different, that difference does not seem to be in the way the highs are reproduced. Of course, my advanced age (way up in the 50s) may affect the way I hear highs. My son, with a much younger set or ears, has made the same statement about them sounding the same to him. Really, if there is a difference between the two tweeters it is a bit hard for me to see what would cause the difference. Once you get inside the tweeter, you find exactly the same diaphragm and voice coil (same exact same EV part is used in both). That is the part that makes the sound. The horn is essentially the same so that leaves the type of magnet as the only real difference. I believe that EV changed the magnet type when the alnico magnet became too expensive. I don't think they went to ceramic magnets with the idea being that it would be an improvement. Neither of the two tweeters are currently being produced by EV and the only part for them that EV still produces is the diaphragm. EV still owns the tooling to produce them but has no plans to ever produce them again nor do they plan to sell the tooling to another company. They have had offers for the tooling.

Bob

[JohnA]

Mr. Lascala,

PLEASE DON'T SHOUT!!!

I have several pairs of each and cannot hear a difference. The K-77 begins to roll-off at about 10k and the K-77-M starts dropping around 14 or 15k. That is about the only difference. For that reason, I prefer the -M, in case there is some HF above 10k in a piece of music I'm listening to. I don't want to miss anything. I keep a K-77 as a spare.

[Malcolm]

Yep, the only difference is a couple dB better high frequency response. I, too, cannot actually hear a difference. The difference was covered in a Dope from Hope at the time of the changeover. Maybe someone who has it can post it. If I were in the market for some, and I could get either at the same price, I would take the K-77-M because it is "better." Otherwise, I wouldn't worry about it. FWIW all my speakers have K-77s.

[mr lascala]

thanks for the response, l am going to leave the k77m ,s in my lascala,s l was thinking also my k77,s could be tired. by your response the m,s are a little better in the top end department they don,t roll as soon.

[Trey Cannon]

The alnico K-77 began appearing in Klipsch products in 1957. PWK used to have to sort them into three different sensitivity batches, and then do three slightly different networks for each variant to accommodate them. They eventually got consistent enough in the late 60's to drop the sorting. The point is that both versions have had variability, but the K-77-M has had far less. When people say they've compared the old with the new, it is unlikely that they really know where each falls in their respective tolerance ranges. When the change was made (for cost reasons), the nominal vs. nominal difference was inaudible to all at Klipsch, including PWK.

[Srinath]

I know this is an old topic. But I didn't want to open a new post.

My 86 Khorns are all original except the XO caps. I have a square tweeter that says K77.

Is it a K77M or the K77.

 

[WMcD]

In my view that is a square (or oblong) magnet which is made from a slurry of ferrite.  The slurry is called "mud" and therefore it is an M.  It looks like there may be Z brackets but I don't know how that affects a suffix.  ("q, s"???)

[Srinath]

Nice, M for mud. But yes, thanks for the knowledge and prompt reply.

I have a round magnet EV sitting around. Worth a swap and listen ?

Those oval lenses I've seen on this forum and ebay - is that worth a shot.

I've been very happy with the Khorns, to the extent the few months I tried to sell them, I felt any speaker I tried seemed to either have too low sensitivity (wharfie 90's) or boomy bass (kenwood 77's) or lack bass (yea this was asking for it a 4" woofer in a bookshelf with a 2X3" carver ribbon tweeter).

That ribbon tweeter in the spot the K77 is would light it up now that I'm thinking about it - but nothing wrond with the one I have there now, it works well with the mid and the folded horn bass bin.

[WMcD]

https://en.wikipedia.org/wiki/Ferrite_(magnet)