Cornwall B-3 Crossover Compatible w/K-55V?

[Tomski]

Hey Guys I was just thinking about the corns1,they were rated at 98db/1watt/4ft

In the Klipsch manual "A Legend in Sound" it states that to convert the rating to 1meter add 2db.Not sure if this helps?

My model#s are 36Y225/6

Tomski

[Daddy Dee]

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On 12/6/2004 8:10:57 PM DeanG wrote:

O.K., let's look at it like this:

The Type B and B2 both use the T2A with the #3 tap for the squawker.

We know the Type B and B2 were used with the K-55-V and K-55-M.

We know the B3 also uses the T2A, as well as the #3 tap for the squawker.

We know the K-79-K has roughly 3db more output than the K-55-V/M, and the two are not interchangeable.

If I'm building a Cornwall, I don't think I would use the B3 network with the K-79-K -- which is the driver for the Cornwall II, has 3db more output than the driver used with the B3, and used a network with the 3507 autotransformer.

Questions I have at this point are:

1) Do the Cornwalls with the K-79-K/ B3 combination have the squawker attached to the #3 tap on the T2A? Maybe they're on the #2 tap. Someone needs to look.

2) What are the attenuation levels for the taps on the 3507?

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'

Dean, I think I'm tracking your process here. Just a couple of points to make sure I'm understanding it.

Above, you mention the K-79... that's the tweeter, right? Did you mean the K-57? Or something about those two elements being used in the same cab?

The other thing is, if I'm hearing this right that there are two random Ebay sellers who over a couple of years are parting out Cornwalls and stating that the K57 and B3 came from the same cab. So that seems fairly reasonable to assume that some Cornwalls were shipped with this combination during a transition.

I think you are onto something to find out which autoformer taps were used on the squawker in this transitional Cornwall. That would make sense as the factory solution to a more efficient K57.

Even if it's not what happened, I'd think it would be a small thing to modify the B3 if needed.

If we had one of these drivers to send off to Bob Crites to test, that would be interesting. I'm sorry that I sold my K57/K601's now. Still have the B-3, though.

[colterphoto1]

It's time for a Klipsch person to check the archives and check in here. MODERATOR????

We need an accurate record of the apparently experimental phases of the Cornwall cabinets, please?

Michael

[mike stehr]

These are rare?

[mike stehr]

I know these aren't very common.

[Deang]

Well Mike, according to Dennis they're rare, and that's good enough for me.

Good catch on that typo Dee. I was thinking K-57-K and typed K-79-K (the tweeter). I went back and fixed the post, which now means no one will know what in the heck you're talking about.

Michael, that's why I asked about the attenuation levels of the 3507 autotransformer that's used in the Cornwall II. Maybe it's not so important since we know the K-57-K has 3db higher output. For now, I'm thinking take that B3 network, drop to the #2 tap, drop the 2.5mH to the #1 tap, and change the 5uF cap to 2.5uF.

I have the C-II schematic at work -- I'm curious about the tweeter section. Are you going to be using the K-77 or the K-79?

Where's the real filter guys when you need them?

B3.pdf

[formica]

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On 12/6/2004 2:14:38 PM mike stehr wrote:

The '83 Cornwalls I own have the B2 network with the K51V, and K77 tweeters.

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Same here... my original unopened (before me) 1982 Cornwall I consisted of:

Tweeter: K-77-M

Mid driver: K-51-V with metal horn

Woofer: K-33-E

Network: B-2

You can check out some images at my Diaphragm Replacement for the K-77 Tweeter page.

Later...

Rob

[colterphoto1]

Thanks for the uhhh clarification Dean. Lets review.

My B3/K57K Cornwalls are a factory-installed rare breed, yes? I mean, it COULD have happened since there's more than one of us. Had no idea how much they jimmied with this design. Makes ya wonder if they're so rare, were they an experiment that failed?

Do I need to have the current owner (prob not original owner or even a user) diagram the current wiring prior to disassembly and shipping? Or can you walk me through it from raw components? I know which end of the soldering iron to hold, can someone talk me through minor mods? I'd like to work with them a while before performing any major updates. I'm not sure, but my 75's may have B2 xovers, so it is possible I could do an a/b comparison whilst in the demolition stage.

I really need some more confidence here. Still feel like I'm buying pig in poke.

Thanks,

Michael

[Frzninvt]

Jesus guys you are all going with nothing but speculation. The point is the B-3 networks that were installed and working in these speakers with these drivers (K-33E, K-57K, K-77M). The '85 Cornwall II crossover was totally different than the B-3. The speakers that these B-3's came out of have K-77M tweeters in them and not the K-79K tweeter.

You guys are worrying poor Michael over nothing, you have no facts. These B-3 networks are set up to run the combination of drivers that were installed in those particular Cornwalls period, so they will work when they are once again installed in another cabinet with no modifications or adjustments necessary.

Didn't you read the comments that I posted from Steve Phillips at Klipsch that the B-3 was setup to run the K-57K and not the K-55?

C'mon people.

[colterphoto1]

Thanks Frzninvt for your support. However, even with the knowledge and backing from Klipsch (could you post Steve's entire comment or I'll look in SEARCH) that the K57K/B3 was a valid, working, factory combination, I wonder...

If it was soooo rare, (and I hate to question their production flow, but hey a $ is a $, they wouldn't even print new CWII labels for a while right?) were they just using up the last of a certain component, the B3, with a short-lived mid driver K57K until the new CWII xovers came in? Even then, once they had these xovers, they went BACK to the K55 driver. What was wrong with the K57?

See how my mind works. SOrry to be a doubter, but until I get good word from KLIPSCH, (how bout a brochure showing this combination?) these parts will be getting dusty on the shelf or sold to the next sucker on Ebay. For those of you who are just playing a guessing game with my hard-earned components, you guys owe me $534.

BTW, mine were advertised to have the K77, but then again the guy said they had K55, so he has not idea either. That should have been my first hint. Wish I'd pulled out of paying based on his advertising the wrong item #. Had a chance to. Too late now!

Michael

[Frzninvt]

You got it wrong, they continued with the K-57K onto the '85-'90 Cornwall II until production ceased for the Cornwall altogether. It was by no means a short lived midrange. It might have even been carried over into the Chorus loudspeaker as well I'll have to check.

Yep I just checked, the K-57K was used all the way through the Cornwall II's life and even carried over into the Chorus so uhhh it is not rare nor was it shortlived either! Guys, guys, guy you are making mountains out of mole hills here.

The Chorus II used a Tractix type midrange horn and I would presume a different driver.

P.S. I did post the entire response from Steve P. above!

[colterphoto1]

WWWHHHHEEEWWW, could you feel my blood pressure drop? I did put a note into our humble moderators in an attempt to get some history on the evolution of the Mighty Cornwall, for all concerned.

So at very worst, I'm looking at B3, the last version of that crossover, with the first used of the K57K, right? Then they went full bore into new model CWII and designed a fresh crossover for that. So at the worst, maybe I might need to tweak the crossover a bit? And my driver is not likely to blow up soon and big daddy Klipsch would have repair parts?

I feel so much better, but this was a great excercise in how suppositon can get some members waaaay out on a limb. Let's be careful out there please

Thanks again Frzninvt (whose moniker I can now spell from memory- what does it mean anyway?)

Michael

[Frzninvt]

Michael, no tweaking of the B-3 will be necessary at all to run the K-57K, it will be plug and play! They were already working that way in the speakers that they were in!

C'mon Michael, "Freezing In Vermont" (Frzninvt) or "Frozen In Vermont" this time of year.

[colterphoto1]

Thanks, I finally got the VT part, now I'll always remember. I do have a tickler out to Amy to please ask Trey for a little Corn history if they have the time.

Michael

[Deang]

"My suggestion would be no, you could not use the B-3 with the K-55-V..."

I want to understand how this statement can be right. Attached is the schematic for the B3 network. It uses the T2A with the #3 tap -- same as the Type B. So, it has the same level of attenuation. This setting works for the K-55-V in the Type B, but not the K-55-V with the Type B3 -- which has the same settings? This makes sense to everyone? What am I missing here?

"There are spl differences between the 55-V and 57-K, 57 is about 2 to 3 dB higher. I do not have specs on them, but the network differences are easy to notice."

Steve says the K-57 has 3db more output than the K-55 (which was used with the Type . What's to speculate? Using the T2A with the #3 tap on a K-57 will net 3db higher output than the same settings with a K-55.

"Not sure if you have the B-3, but I will send it along. Caps and tap points are different. You may be able to just change the tap points and the mid level be correct. I would suggest that it may not cause any problems using the network, just may not sound "right."

He says "caps and tap points are different". Different than what?

Hey, maybe I'm just obtuse -- can someone help me figure out what's being lost on me here?

B31.pdf

[Frzninvt]

DeanG you are most likely correct that the B-3 can be used with the K-55V and the K-57K but that is the information that Steve Phillips at Klipsch sent me and I had no reason to doubt him.

On the flip side I see your logic and it seems to me that it would work with either driver, hence my initial reason for purchasing the damn things. I sold them to Michael because they are the matching networks to the drivers he purchased to complete his center channel project.

Perhaps the engineers, techs or what have you at Klipsch need to be more thorough in their research. I asked a genuine question, and I thought I had gotten a researched response but apparently not.

I give UP!!!!!!!!!

[Deang]

I'm dialing the phone. I'm calling Steve and Trey.

[colterphoto1]

Thanks Dean and Frzninvt, you guys are getting so far beyond me that I'll wait for an 'official' or other reasonable response. I appreciate all the thought that has gone into these posts. I also have the same suspicion that two of us randomly buying 'systems' off of Ebay must have gotten original Klipsch engineered component packages. I'm just still very unsure as to how experimental, common/rare, or correct these are from an engineering standpoint.

Why would a company like Klipsch ever scrimp on components, using ill-advised component packages just to relieve inventory, or to release experimental matches on an unsuspecting public? If these systems were within the company's engineering expertise, why where they produced for such a short period of time or sporadically? The K57K did indeed live on in CWII and Chorus, both of which were eventually discontinued. It sounds like the B3 was discontinued very shortly after these CW's were made in favor of the new CWII xover. So what was wrong? Did I indeed purchase a 'rare' unfavorable combination? Until these questions are answered, these babies will collect dust and that will be the end of Michael Colter, Klipsch, Forum, and Ebay. Just too expensive of an error.

Again, thanks for those genuinly concerned and doing research. It's my fault alone that I got the Ebay itch and purchased blindly. I'm quickly losing faith in Klipsch for their haphazard manufacturing schedules if indeed that's what occurred here.

Michael Colter

[Deang]

I called and spoke with Steve Philips. Steve Bailey was supposed to call me back, and I think he just ran out of day. I will also call Trey tomorrow. Don't get your panty hose all twisted up Michael. I'm the resident rookie around these parts, and I very well could be wrong. If I happen to be right, we'll find a fix. I'll build you a set of free networks before I let you wander out of Klipschland! Now relax!

[colterphoto1]

Thanks Dean,

Whilst pondering my fate with other speaker manufacturers, I noticed that I had rapidly proceeded into NO LIFE land. Reminds me of the old Jimi Hendrix 'ain't no life nowhere'. Perhaps the message is to stop spending so much dern time and dollars frustrating myself with my horribly mismatched $7,000 pile of junk and get back to enjoying the music!

Oh, and my new assistant also works at Victoria's Secret, so we all wear unbunchable panties around here or none at all!

Michael