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Cornwall help . . .


Roadhog

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No joy through multimeter, opened up tweeters, in both the fine wire leads which connect the diaphragms to the plastic housings were broken. Damn those leads are fine. Either from heat or being brittle, I can see why they let go at some point during 36 years. So . . . I'll be calling Bob tomorrow to discuss replacements - 120/125 and crossover kit.

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Bob Crites is the man. He can supply worthy replacement diaphragms for the K77/T35s or provide CT125s or CT120s, whichever your budget allows. You cannot go wrong taking advice from Bob.

Welcome to the forum.

Edited by DizRotus
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Takes the load off the mid range driver cause the Crites tweeter can go down lower to meet the 4500 point. I like it but did not A/B it to confirm my opinion I just trusted Bob.

  But that crossover will not work in the Cornwall because of different horn just to be clear.... but the tweeter will work fine.

 

What is the normal crossover point?

JJK

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As far i as know its 6K on K-horn, Scala,Belle,Heresy,Forte....that was from looking at 1985 buyers guide audio magazine. So maybe the 4500 crossover may help all of them. Maybe someone knows more than me .... Im sure someone does. lol

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Order is in with Bob, new B crossover network/board, C120 tweets to replace the K77Ms, all shipping today.  I spoke with Bob, which to a Klipsch fan like me, was really a treat, if that makes sense.  Having never modified or needed to replace any parts on any of my Klipsch speakers (Forte2, 3.2, 2.2, SW10) Bob assured me I was heading down the right path with my purchase and my CWs.  Shipment should arrive Friday!!!! -- Bob also mentioned I shouldn't wait for my Forte2 tweeter diaphragms to give up before upgrading to his much better sounding titaniums.

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To my ears, compared to a forte II ( always lower case 'f' as in the musical notation it's named after), with their more modern design tractrix horn, will sound more open and natural in the midrange than the exponential horn of the Cornwall. Your ears do not deceive you. 

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I noticed that too when I open up the box.  The woofer lead looked really snug, but has just a small bit of slack keeping it from being tight.  I haven't opened the other speaker yet to compare.  Is that woofer lead normally very slack?

About as much as what's on the other drivers, that's all.

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In the early days of what we know as the CW they were called CWII as shown in one review.  This was probably to distinguish them from the still earlier CW which had the vertical mounted midrange. But after that the nomenclature was changed to just Cornwall, from what I see.

 

Your photographs show a horizontally mounted mid horn with K55 mid driver and K77 square magnet tweeter (K77M).  The horns and woofer are mounted to the back of the front board.  This is definitely a Cornwall, as it was call for many years.

 

In 1985, the main site says, the Cornwall II was introduced.  The horns were plastic.  And a K77 was not used. They and the woofer were mounted to the front of the front board.  The crossover might have be mounted to the input terminal cup.  Someone will know.

 

Therefore, what you have is not a Cornwall II of the type made from 1985 (which makes sense re the date you have)..

 

Therefore you are looking for a diaphragm for a K77M if you want to use that tweeter. 

 

WMcD

Edited by WMcD
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In the early days of what we know as the CW they were called CWII as shown in one review.  This was probably to distinguish them from the still earlier CW which had the vertical mounted midrange. But after that the nomenclature was changed to just Cornwall, from what I see.

 

WMcD

 

Actually, the early Cornwall speakers that had vertically mounted mid and tweeter horns were designated as the CWII. 

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As far i as know its 6K on K-horn, Scala,Belle,Heresy,Forte....that was from looking at 1985 buyers guide audio magazine. So maybe the 4500 crossover may help all of them. Maybe someone knows more than me .... Im sure someone does. lol

yeah, i think you are right... 6k it is 

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Thanks Munkiman.  Attached is the article which I mentioned about the so called Cornwall II.  There is no info on the orientation of the horns but I suspect they are like what we know as the Cornwall

 

FWIW, the very early CW had port which ran the height of the box with a board behind it.  Sort of a T in cross section. When that changed to the present form I don't know.   I also don't know how that relates to the Cornwall designed to be used on its side or bottom.

 

My understanding is that PWK designed the T type and it had unusual parameters, probably the mass of air in the port which may have been greater than what others were doing.

 

Back in the day ports were just a hole in the baffle and thus 3/4 inch deep (shallow).  According to an honorary uncle,  builders would start with a large rectangular hole and partially cover it with a movable, small board to block it partially.  They'd adjust the movable board to adjust the size of the hole - port.  The desired size was reached when the sound would blow out a candle placed in front of the port.  I suppose that indicated resonance at some freq.  Maybe that of the raw driver?

 

From my recall of the PWK article, he started the analysis with a circuit where the box was a "dual" of the driver.  Maybe in this the mass of air in the port was equivalent (or so) with the mass of the moving system of the driver.  In any event, This must have been a significant departure from the shallow port.

 

 

WMcD

Audio Review 1969 of Corwall II.pdf

Edited by WMcD
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Attached is a timeline for the CW.

 

It doesn't help with nomenclature.  I see it says the horizontal version of the CW was discontinued in 1974 -- the flipable type?.  That may be the type where the orientation of the mid and tweeter were thus adjustable by that means.

 

I would have thought that the CW in the article would displace the flip version in 1969 but this is just guesswork.

 

All comments and corrections are welcome.

 

Cornwall Timeline cached.pdf

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Thanks Munkiman.  Attached is the article which I mentioned about the so called Cornwall II.  There is no info on the orientation of the horns but I suspect they are like what we know as the Cornwall

 

FWIW, the very early CW had port which ran the height of the box with a board behind it.  Sort of a T in cross section. When that changed to the present form I don't know.   I also don't know how that relates to the Cornwall designed to be used on its side or bottom.

 

My understanding is that PWK designed the T type and it had unusual parameters, probably the mass of air in the port which may have been greater than what others were doing.

 

Back in the day ports were just a hole in the baffle and thus 3/4 inch deep (shallow).  According to an honorary uncle,  builders would start with a large rectangular hole and partially cover it with a movable, small board to block it partially.  They'd adjust the movable board to adjust the size of the hole - port.  The desired size was reached when the sound would blow out a candle placed in front of the port.  I suppose that indicated resonance at some freq.  Maybe that of the raw driver?

 

From my recall of the PWK article, he started the analysis with a circuit where the box was a "dual" of the driver.  Maybe in this the mass of air in the port was equivalent (or so) with the mass of the moving system of the driver.  In any event, This must have been a significant departure from the shallow port.

 

 

WMcD

 

Thanks for the link, Gil.

 

The early Cornwall II speakers had vertically oriented horns (mids and tweets). This is why the linked article states that the speakers could be placed either horizontally or vertically, and that they were finished on all 4 sides. In addition to the standard labels to designate model, finish and serial, there was a second label with 2 "up" arrows.

 

The later Cornwall II speakers (mid '80s) have horns oriented horizontally, just like the Cornwall I (subsequent to the original Cornwall) and the Cornwall III.

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New Crites B Crossovers and C120 Tweets installed last night.  Both woofers rotated 90 degrees- from the leads at 9:00 to the leads at 12:00 (not sure if that was how they were mounted from the factory or if the previous owner turned them- if so, he turned both of them.)  I ran a CW left and forte II right briefly to compare the two (not ideal with different sensitivities, but good enough for a short test.)  Thoughts and observations . . .

1.  CWs bottom is simply more full and detailed- fortes seem to hit all the bottom peaks but lack the detail or presence in between the peaks.  

2.  fortes showed better mid projection and detail- but not by a huge difference- but audible at matching power. 

3.  CWs with the 120 upgrade sound magical up high.  My fortes with stock diaphragms held their own, but just weren't as crisp or detailed.  Titanium for the fortes is next. 

 

Beyond the two channel test, I moved my fortes to the side positions in my 7.1 and did some quick leveling (previously kg3.2s) and WOW- two channel into 7 channel stereo sounded amazing!  Of course that brought in the rest of my speakers to the fight - (2)KG2.2s Center - (1) HSU ULS-15 Sub - (2) Boston Acoustic In-walls Rear.  I'm contemplating swapping in my now unused KG3.2s for Centers.  I could then get the wall mount brackets and hang my 2.2s as rears.  I kicked around moving the fortes to the center position, but I just don't have room.  Other plans, ideas, questions for another thread in another forum, I digress . . .

 

Regardless, simply replacing the 3.2s with the fortes at the side (and the new/old CWs up front) upgraded the detail and range several fold.  Quantum of Solace is on my list for this weekend.

 

I tested with a lot of material, but if you get a chance . . . spin up "One Caress" by Depeche Mode off of Songs of Faith and Devotion- great track for testing, lots of range and detail across the mix.

 

Thanks to everyone for their help.  I was pretty bummed my purchase of the CWs was going to require additional work and investment, but it's been totally worth it.  For reference- total price speakers/upgrades- $1000.  Could have saved about $150 if I'd have just done new caps instead of an entirely new board from Bob.

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thanks Hog for your notes on the experience.  in my case, for a noob to Klipsch, that is highly valuable.  my brother-in-law has a pair of CW's from probably the 70's or early 80's, and I drool over them even just thinking about them.  I've already put the word in that if he ever considers parting with them - which I think highly unlikely, I would like 1st dibs.  CW & Belles/LS are on my "realistic" wish list... hopefully, one of these days, I'll get me some of that.  good job sir, and thanks.

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thanks Hog for your notes on the experience.  in my case, for a noob to Klipsch, that is highly valuable.  my brother-in-law has a pair of CW's from probably the 70's or early 80's, and I drool over them even just thinking about them.  I've already put the word in that if he ever considers parting with them - which I think highly unlikely, I would like 1st dibs.  CW & Belles/LS are on my "realistic" wish list... hopefully, one of these days, I'll get me some of that.  good job sir, and thanks.

I'm a newb on these boards, but have owned various Klipsch products since 1990.  Don't limit yourself to just the "Heritage" models, forte/chorus I and IIs are fantastic speakers (refered to as Extended Heritage.)  If you equally weigh in size, sound and price, you'd do well with fortes or choruses.  Fortes take up half the space of a CW and still manage to provide the Klipsch sound with fantastic range (just less detail and presence in the bottom.)  Still, keep first dibs on the CWs as long as you have the space. 

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Hey I need to replace a black plastic terminal on the back of around 1982 klipsch cornwall.. Can anyone tell me where to get one please.. Im not very electronics oriented so let me say that.. I've attached a picture of what I'm looking for.. Thanks for the help guys/women

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Hey I need to replace a black plastic terminal on the back of around 1982 klipsch cornwall.. Can anyone tell me where to get one please.. Im not very electronics oriented so let me say that.. I've attached a picture of what I'm looking for.. Thanks for the help guys/women

Your photo didn't make it, but you can go to Parts Express and find what you need.

 

http://www.parts-express.com/cat/binding-posts/1506

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