Cornwall Mods Glossary

[colterphoto1]

I'm in the process of assembling as many of the Cornwall modifications as possible so that when I rebuild my old babies this winter, I can do it all at once. Please post your most detailed info here, and I will organize the various suggestions and parts listings to make available to all members. If you have any diagrams, especially with any dimensions for the various(?) cabinet sizes, that would be helpful too.

Basic listing will include structural mods for double back panel, strengthening front panel, 5-way binding posts, remount tweeter and squawker, and dampen woofer frame and squawker horn. Electrical will include minor x-over mods, wiring mods, total xover upgrade. Cosmetic includes BLO application, grill repair/replace, veneer application.

Any other topics appreciated. It's a labor of love people!

[Klipschfoot]

How about editing your first post with all the links that you collect.

I'll start with the only I have:

A cabinet modification.

[Dflip]

Here is a drawing of the B network for a pair of Cornwalls. It includes some mods I have done. I am going to try Jensen PIO caps when they arrive from Dean.

[IB Slammin]

The back.......

[IB Slammin]

another....

[IB Slammin]

Front .......

[dbflash]

I rewired my Cornwalls,added Deflex Panels to the rear panel and added Cardas Binding Posts.

If you use any of the suggestions be sure to thank Dave Mallet and Mike for this post.

Danny

I have this saved in a folder.

This was posted maybe a year ago:

Here are the secret modifications that Dave Mallet referred to which he and Bob Lemker heard the results of at the last meeting of the DFW Klipsch Forum. They have been very kind in their positive comments. (Sorry, Dave for taking so long to post. Other issues.)

My goal was to improve bass response, tighten the bass and smooth the mid-range. In addition, didnt want to do anything that could not be reversed.

I have been thinking about modifications to my Cornwalls for about a year. Im not a frequent poster on the forum, but I regularly lurk and take note of all the mods I see mentioned / discussed. The only semi-original modifications I made were the first two listed.

The Bad News: All modifications were done at once.

The Good News: They worked beyond my expectations!

These modifications were made to a pair of stock (at the beginning) 1980 Cornwalls, with standard B2 crossovers. Previously all contacts were cleaned with Caig ProGold with no noticeable improvement. I have a second pair of 1975 Cornwalls and in the future will take the time to do each modification separately to determine the actual secret, although my current belief is the 12 gauge silver wire was the most significant mod.

There is a significant improvement in base response and it is tight. The mid-range is smoother, but there is still some work to be done with the mid-range.

Modifications:

Mod: Pure (.9999) silver, 12 gauge solid wire from the crossover to the woofer.

Purpose: Improve bass response. The K-33 has a resistance of 3.5 to 4.0 ohms and any reduction in the resistance of the wire is a good thing.

The silver wire was purchased from a jewelry wholesaler. I first polished the wire with Blue Magic, the finest grained metal polish I am aware of (so fine that you can polish the milky haze out of convertible rear window, which I have done). Second, I cleaned the wire with Caig ProGold. All of this was to prepare the wire for sealing with 1/8 commercial 3M FP-301 Clear heat shrink (Parts Express part # 082-026). This may seem obsessive, but my concern was to protect the raw silver from future tarnishing.

Mod: Gaskets for the Squawker and Tweeter.

Purpose: Reduce the vibration and seal the Squawker and Tweeter to the motorboard.

Previously when swapping the Squawkers and Tweeters between the 1975 and 1980 cabinets, I noticed that there was rough flashing on the mouth of 1975 Squawkers. I filed off the flashing and placed on a very flat surface to be sure they were flat and found they werent. Then I checked the 1980 Squawkers and found that they too were not flat. So I checked the tweeters and they were not flat either. This made me concerned about the seal between the speakers and the motorboard. The solution was the gasket. The gaskets were made from a VE-1 Vinyl Damping sheet (Parts Express part # 268-030). The 10 x 13 piece is enough for a pair of Cornwalls and is about a 1/16 thick. Note: There was not a gaping space between the horns and the motorboard, but any space is not a good thing.

Side benefits of the squawker gasket:

1) It adds addition force on the back of the speaker and this may reduce some vibration on the back and thus tighten the bass.

2) The vinyl damping material absorbs vibration from the motorboard and thus insolates each speaker from the other, to some degree.

Mod: Installed a 2 x 1 x 22 ½ Hard Rock Maple brace on the interior side of the motorboard, between the Squawker and Woofer.

Purpose: Reduce flexing of the motorboard and thus tighten bass.

This idea was taken directly from Roger Floths article Equalizing the Klipsch Cornwall published in Speaker Builder on March, 1989. An additional benefit is to reduce some vibration to the Squawker and Tweeter. It is very important that the 1 face is milled very flat and smooth to make the best contact to the motorboard. The wood selected must be very stiff. Both Hard Rock Maple and Ash were suggested to me. I chose Hard Rock Maple.

Mod: Monster Original from the back of the binding post to the crossover.

Purpose: Reduce resistance.

Mod: Dampen Woofer basket with rope caulk

Purpose: Cut noise you dont want.

Mod: Dampen squawker horn with rope caulk.

Purpose: Cut noise you dont want.

No changes were made to the wiring to the Squawker or Tweeter.

I welcome the your comments, questions and hope to see some of you at the next DFW Klipsch Forum meeting

Mike

[IB Slammin]

"...Mod: Installed a 2 x 1 x 22 ½ Hard Rock Maple brace on the interior side of the motorboard, between the Squawker and Woofer.

Purpose: Reduce flexing of the motorboard and thus tighten bass"..........

To reduce deflection in the motorboard, I used 2"X2" steel angles with the thought that steel would be a bit more rigid than any strip of wood. If you buy an 8' stick, one can find a perfectly straight 22 1/2" piece. No need to trust some guy on a saw or plainer. RIGIDITY (sp?) in the point!

Then, screw & glue...screw & glue.......

Regards,

Terry

[colterphoto1]

Thanks gang, we're off to a great start. I'm saving all the files and downloads you post. Will present the Forum with a more detailed index list as mods are acquired to make sure we don't leave anything out. Most of these mods could apply to Heresy as well I think.

Here's a new one- how bout various mods to convert a Horizontal (upright cabinet )Cornwall to a 'vertical' (cabinet laying down) for use as HT center channel. Couple of different ways to attack this one.

Michael

[TBrennan]

DBflash---As for Mallet's mods; I'd like to know the mechanism by which going to wire with a little less resistance changes the alignment of a vented box. As far as I know there is no such mechanism. The things that control an alignment are driver fs, vas and QTS, plus box volume and vent size. Nothing about speaker impedence (not resistence) or wire resistence. Mallet sounds like the kind of a guy who thinks chrome valve-covers really make a car go faster.

And even if such a change did ocur then such an alignment change would be detrimental, not beneficial, given that the alingment was arrived at by a competent designer, ya know, ole PWK, that guy.

What's weird is that almost every tweak claims to be beneficial. Hardly ever are tweakers honest enough (with themselves as well as others) as to admit a mod had no benefit at all or was actually detrimental.

[Deang]

The Qts (combination of electrical and mechanical losses) of the driver, combined with the total DCR of the woofer circuit aligns the driver with the enclosure. My understanding is that most speakers are typically slightly underdamped to begin with, so knocking the DCR down a touch doesn't hurt anything. Most decent ears probably wouldn't even notice the change if the DCR isn't dropped by more than 30%. However, it can go from "can't tell the difference", to "that sounds like sh!t" pretty quick if you're not careful. Since the DCR is used in the alignment calculations, it's usually not very wise to take it down as low as possible.

Considering the distance from the crossover to the drivers, you'd have to use something like 2 AWG wire to make any difference.

[colterphoto1]

On the rewiring topic, suppose the listener is satisfied hooking up his Klipsch with good 16ga zip cord or equivalent. Then is there ANY benefit to using Monster or other hot-rod wire inside the cabinet? Likewise then, is the modern internal Monster-cable wiring a bit of marketing unless one goes the full route of bi-wiring one's cabinets?

...not knocking the practice, just wanting to get informed...

[michael hurd]

As long as the wire is not oxidized to death, and the connectors are not corroded, changing out the internal wire isn't going to make any perceptable difference.

[3dzapper]

"What's weird is that almost every tweak claims to be beneficial. Hardly ever are tweakers honest enough (with themselves as well as others) as to admit a mod had no benefit at all or was actually detrimental."

"Considering the distance from the crossover to the drivers, you'd have to use something like 2 AWG wire to make any difference."

Wrong Tom and Old Capacitor Breath! I tried replacing the leads to my squaker and HF driver with different materials ingluding 10ga and silver plated OFC( can you say too bright?) and returned them to the original tinned copper and said so openly on this forum.

Rick

[dbflash]

TBrennan

You will have to ask Dave.

I rewired all my speakers with DH Labs Silver Sonic T14 because I liked the way it sounded before I upgraded my speaker wire to another brand.

I had 40 feet laying around, so I rewired my speakers, added the new binding posts and put in the Deflex Panels to one speaker and put it back into my system. I could hear a difference with my 50 year old ears as soon as I started playing music. Better bass(seemed tighter) and the Mids sounded more open. I rewired the other speaker and added the Deflex Panels. I'm happy with the mod.

I also did the same mod to my Heresy's.

It took about 2 hours out of my life. I'm happy and thats all that counts. Please do not rewire your speakers or do any mods. I would never tell anyone that to make your system sound better you need to replace the internal wiring, use this type of speaker wire or this brand of interconnects.

I know this is going to chap your butt and will send you into a typing fit, but here goes.

I just finished redoing my living room last night. I am going to try placing my speakers in another spot. I can no longer use my 8 foot speaker wire. Last night I went to Home Depot and bought a roll of their Monster cable knock off cable. I personally don't like it. When I first got into this I was using it. It was too bright for me. I still use it for my surrounds in my HT, but do not use it for anything else.

If I leave my 2 channel in the new configuration I will have to buy 80 feet of speaker wire at $10 a foot.

Again I am not telling anyone they need to buy this brand or replace their Home Depot wire.

I am lucky that I live by myself. I can either buy a coffee table or buy new speaker wire. I am going for the speaker wire.

Will my system sound any better than yours. No it will not. Is it hurting anyone that I am doing this. I can't think of anyone it is hurting.

I like to experiment. I have been disappointed with some of my upgrades and happy with others.

This to me is so simple. If you want to change out different components and can afford it, go for it. If you can't or don't want to, then just leave it alone and be happy.

If you are reading a post and someone states that they did a mod or added a $1k IC take it with a grain of salt. If you have the time and money try it. It's not going to hurt anyone.

Like I said I am VERY lucky in ways. I have no wife or kids. Everything is paid for, except my house. My only addiction is CD's and trying to make those CD's sound good. I have never told anyone that their choice in equipment is bad. I have friends with all types of systems. I have never bad mouthed their system. Some sound very good and others are a little weak to me. If THEY are happy that is all that counts.

I met my Sister and her husband down at the beach a couple of weeks ago. She asked me to bring a boom box. I didn't have one. I went to buy one and they were huge and Star Wars looking. I ended up buying a Phillips Shelf system for $150. We took it out of the box and for the week we were down their it sounded awesome.Will I replace my system with it,no. But for what it is and what we used it for I could not have been any happier.

Sorry this is so long, but this just put my butt in the chap mode.

Again if you want to mod do it.

Danny

[TBrennan]

dbflash---Huh?

[Good2BHome]

To set the record straight, I am the author of the post and owner of the "Silver" Cornwalls refered to above.

The orginal post is located in the "2 Channel Forum" as "Revealed: Secret Cornwall Mods at DFW Forum"

The address is:

http://forums.klipsch.com/idealbb/view.asp?topicID=30963&forumID=68&catID=19&search=1&searchstring=&sessionID={851D2543-54E0-4154-8710-6EB3A0ECECD7}

I was responding to positive comments in a previous post by Dave Mallet back in January 2003.

http://forums.klipsch.com/idealbb/view.asp?topicID=30310&forumID=68&catID=19&search=1&searchstring=&sessionID={851D2543-54E0-4154-8710-6EB3A0ECECD7}

Now my comments for this post:

As clearly stated in the post in question:

"The Bad News: All modifications were done at once.

The Good News: They worked beyond my expectations!

These modifications were made to a pair of stock (at the beginning) 1980 Cornwalls, with the B crossovers. ....in the future I will take the time to do each modification separately to determine the actual secret, although my current belief is the 12 gauge silver wire was the most significant mod."

I still own the Cornwall pair and two other Cornwall pairs. I've owned two additional pairs in the last three years. In addition I've listened to at least six other pairs in the DFW area. Without any doubt the modified Cornwalls have significantely better Bass than any others I have ever heard!!

Which mod or combination of mods improved the Bass? I don't know, but I and anyone that has heard them agrees that it is the best Bass they have ever heard from Cornwalls!

So, if someone wants to say it's not the silver wire, then OK it not the wire. So what! They sound great!

If I can get the 1974 Verticals, I recently bought, to sound as good, then I will sell the "Silver" Cornwalls this fall. If not, then there will be a very fine pair of 1974 CWL Verticals sold this fall.

I'm still trying to figure out if there is a way to put the brace on the motherboard of the verticals.

"dbflash" Thank you for the positive comments.

To get this post back on track: I'm looking forward to reading about other Cornwall mods.

Mike Walters

[mike stehr]

Better woofers.

[dbflash]

Good2Bhome,

Sorry about leaving your name off.

It is just such a good read I cut and pasted it to a folder.

If anyone ever asks about mods for Cornwalls I always bring this out.

I hooked my system up last night and this morning.

If anyone is going to change the binding posts out I would put them close to the bottom of the speakers instead of the top. I ended up having to rotate the back panel on my Heresy because the binding posts ended up rubbing my midrange horn. I am going to see about doing this when I take the panel off to try the chaulk mod to the squaker and tweeter. It will save on the amount of wire needed to be purchased by having the posts lower.

Again Mike sorry about leaving your name off and a great mod post.

Danny

[dmethe3]

You guys are awesome! It is so much fun to read about what you agree and disagree on! ALSO, as for the Corn mods, are different years in need of different stuff??