OK - I was wrong (or, Cornwalls are AWESOME)

[popbumper]

Yup....

This diehard Forte fan with his 5 Fortes and two KG2 rears has learned his lesson.

A few months back I built myself a set of new Cornwall cabinets and populated them with components from a tired pair of 1976 units. I built some "Dean G inspired" networks, and eagerly hooked them up for critical listening....

and HATED them. I found the midrange WAYYY too bold, it actually hurt my ears. After 24 hours, I pulled the wires off, and set them aside to collect dust.

Being a tinkerer is a wonderful thing. Taking up a lot of excess room, I first thought to sell them - but also realized that I could (shudder) "re-tap" the autoformers and tame the midrange. After all, being my speakers, I should NOT worry that this type of thing (shudder again) is against the principles.

Principles be damned, I knocked 2 dB off the midrange and tweeter for kicks. I eagerly again hooked them up, hoping to hear something different.

While "holding myself down" doesn't necessarily conjure up the proper mental image, perhaps "literal tears" does. I have been auditioning these speakers the last two evenings, and, well, this stuff is somtimes hard to describe, but here goes:

1) The Corns dissapear; the Fortes do NOT - I was ALWAYS aware of the "boxes" when listening to the Fortes, even with K-stacks.

2) My center Forte STILL blends very well with the Forte fronts, in fact, the Forte seems BETTER now. I upgraded this one also with a K-stack that used Mundorf silver/oil caps, and it's LUSHHHH....

3) The whole experience is FAR more enveloping. The Corns FILL the space, they are RICH, deep, and alluring. The bass is WONDERFUL. Horns (as in brass instruments) are amazing.

So there you have it. What I love MOST about audio tinkering is there seems to always be anotehr surprise around the corner, one more wonderful than the next. And, every time, I ask - "how can it be any better"? I DON'T know - but I think the Corns are gonns stay for a while. Never thought I'd do it....back to LOTR. Oh, yeah, Terminator 3 was really impressive as well....

Chris

[colterphoto1]

Did I tell ya? Did I tell ya? Did I tell ya?

Nice review Chris- I wonder how far your original or modified xovers were from the original design?

Are you thinking of maybe doing a CW xover in your series? There's a lot of us out here...

M

[Duke Spinner]

yea ...... like for CW 2's ......

[jwc]

I must have missed he thread where you commented on this before.

I still say my favorite speaker from Klipsch is the Cornwall. There are a lot of those out there.

I have done quite a bit of Cornwall mods to the point where I don't own one anymore. Ironic huh? But if I were to Purchase a Klipsch speaker again....It would be a Cornwall.

The majority of owners out there don't realized what can be further tapped out of the Corns with network tweaking or network exchange. But even w/o an upgrade or tweak...it still rocks.

jc

[mark1101]

Did you put any Mundorf silver oils in the CW network by any chance? Comments?

[Deang]

Let's look at the way it was, what you originally built to replace it, and then what you ended up with.

No matter what you do with the network, you have a woofer trucking along at about 99dB/2.83v. Now, I believe this factors in some room gain, but how much I do not know. So, that number will fluctuate depending on placement, and if not in a corner or with at least some boundary reinforcement that number will drop. The tweeter is rated at 105dB, and on the Type B network it is attenuated by 3dB (tap 4). I suspect another dB of loss in the tweeter filter section because of the way it is terminated and feel comfortable saying the Cornwall tweeter is running pretty close to 101dB. On the K-600, the K-55-V is at 107dB, and coming off of tap 3 we get 6dB of attenuation and now see her also at 101dB. All in all -- well balanced. However, like the Heresy -- without some boundary reinforcement the mids and highs will dominate the signature.

You then built the "DeanG inspired" (lol!) network. The network is really just a modified version of John Albright's DHAxover -- a first order constant impedance network for the Klipschorn/Belle Klipsch/LaScala. A 10 ohm swamping resistor is used on the autoformer to bring down the impedance, and then the parts behind the autoformer are scaled for the new impedance. The Type B squawker section has a reflected impedance of 60 ohms, while the modified network brings it down to 6 - 8 ohms. The important thing here is that both of these networks are tapped out the same as the Type A and Type B. The DHAxover uses taps 5 and 4 (like the Type A), while the Cornwall version uses taps 4 and 3 (like the Type . IOW, the attenuation levels are roughly the same. I say "roughly", because the swamping resistor introduces some insertion loss that wasn't there before. However, I've compared the DHAxover to the Type A directly many times and all I can say is that the difference in midrange output is so small that it can't be picked up by my microphone and Behringer RTA. The networks sound different, but it's not because of differences in attenuation. In conclusion, if you think the midrange and tweeter is too hot then don't blame the network. I've sold close to a dozen pairs of the Cornwall constant impedance version, and a couple have come back asking for another for their center channel. People who like the Cornwall with the Type B like the new network very much, and I don't want the design getting a bad rap based on a preference issue related to attenuation alone.

On to what you did.

I'm not going to dispute that the speaker sounds better to you with the top brought down a bit. In fact, the tipped up top of the Heresy and Cornwall are some of the most common complaints I get from people who want something built by me. What I'm curious about though is how you got the additional 2dB of attenuation without redesigning the network. If you left the swamping resistor in place, and are still using the 44uF/10mH combination then you also moved the crossover point when you changed the tap settings.

[Erik Mandaville]

Didn't seem to really blame the network, just change the autoformer settings a notch. I've done that too without any change to component value, despite the fact that I knew what was going on in terms of impedance alterations. The only difference I could perceive was the reduced attenuation. The overall response was just fine.

I agree with the swamping resistor and insertion loss. It's obviously only my opinion, but the networks I've auditioned with swamping resistors sound much better (to me) without them.

Good news on the Cornwalls! I know a few who really prefer them to Klipschorns. With how good our Heresies are sounding, I can see how that might be the case -- or at least be subjectively equal to the big K-horns.

edit: Sort of related to this, I was reading a review in TAS last night, after finishing some grading, where engineers took advantage of a small imperfection or peak in response that would have otherwise resulted in a very linear profile. Instead of ironing the thing out with a filter, which is often done in the name of 'perfect response,' it was left in place because the speaker sounded better that way! I like things like that where designers will go beyond what they know of test and measurement and perfect filter or circuit design -- and go with what, very simply, happens to sound better.

[Daddy Dee]

Popbumper,

You should talk to Colter!

He'll tell you.

[]

[jacksonbart]

awesome

[Guinness]

I also built a set of "DeanG inspired" networks for my Cornwalls. They sound wonderful to my ears and very well balanced. My Corns are placed in the corners of my listening room and toed in slightly. That probably yields some bass reinforcement.

I've since added an Altec 511 horn with a 902 driver. I didn't feel any need to modify the network for that change. I'm now ready to add JBL 2404 tweeters. I expect I may need to pad them down a bit. I now refer to them as "FrankenCorns". Great thing about these mods is they are all easily reversible back to the original Cornwalls.

Great work on the network design Dean. And thanks to Chops and others for all of the threads on Altec and JBL mods.

[jwc]

I also built a set of "DeanG inspired" networks for my Cornwalls. They sound wonderful to my ears and very well balanced. My Corns are placed in the corners of my listening room and toed in slightly. That probably yields some bass reinforcement.

I've since added an Altec 511 horn with a 902 driver. I didn't feel any need to modify the network for that change. I'm now ready to add JBL 2404 tweeters. I expect I may need to pad them down a bit. I now refer to them as "FrankenCorns". Great thing about these mods is they are all easily reversible back to the original Cornwalls.

Great work on the network design Dean. And thanks to Chops and others for all of the threads on Altec and JBL mods.

Those aren't FrankenCorns. Nothing Franken about them. That set up sounds very good. Yes, Chops did this and many before him.

I think the "Alcorn" or the more comical "Voice of the Corn" is more fitting.

I have tried may different networks in the Cornwall/Cornscala. I didn't try Dean's unfortunately but I bet they would be good. They probably "open up" quickly in which I like.

The JBL 2404 is a great tweeter. Using some with some 511's right now. I can bet that you will have to fiddle with your network with the 2404.

[IB Slammin]

I also built a set of "DeanG inspired" networks for my Cornwalls. They sound wonderful to my ears and very well balanced. My Corns are placed in the corners of my listening room and toed in slightly. That probably yields some bass reinforcement.

I've since added an Altec 511 horn with a 902 driver. I didn't feel any need to modify the network for that change. I'm now ready to add JBL 2404 tweeters. I expect I may need to pad them down a bit. I now refer to them as "FrankenCorns". Great thing about these mods is they are all easily reversible back to the original Cornwalls.

Great work on the network design Dean. And thanks to Chops and others for all of the threads on Altec and JBL mods.

IMHO, the only reason to attenuate the CW mids is to lessen somthing that is "not very good". Once the nasty little K600 is gone, and 511/902 is in the loop, let them run.

Consider 3/4" plywood over the back and 1-1/2" X 1-1/2" steel angle on the inside of the motor board just above the woofer. Additional bracing makes it.

tc

[popbumper]

Still surprised and elated at the sound from the Corns. As I listen to more "source material" (really, 100% movie soundtracks) I am very, very pleased with the richness and depth of the sound. I was watching SCARFACE last night, and while the movie certainly does NOT have lots of explosions and other effects, the musical portions (in the clubs, etc.) was excellent.

I bought an A/B speaker switch the other day, still don't have it hooked up yet but plan to do some comparison between the Corns and my original (crossover upgraded) Fortes. Should be an interesting experience.

Chris

[eq_shadimar]

Chris -

About damm time you acknowledged that Cornwalls are the greatest speaker ever! Of course since I have five of them you might consider me a tad biased.

Laters,

Jeff

[colterphoto1]

Still surprised and elated at the sound from the Corns. As I listen to more "source material" (really, 100% movie soundtracks) I am very, very pleased with the richness and depth of the sound. I was watching SCARFACE last night, and while the movie certainly does NOT have lots of explosions and other effects, the musical portions (in the clubs, etc.) was excellent.

I bought an A/B speaker switch the other day, still don't have it hooked up yet but plan to do some comparison between the Corns and my original (crossover upgraded) Fortes. Should be an interesting experience.

Chris

I use a Niles box that has volume controls for A/B testing. I use it to take the efficiency out the equation because the louder speaker will generally 'sound' better to the ear.

It's too bad that modern receivers don't have MONO switches, that would help also. But I put the speakers to be compared in the same acoustic space, feed them the same side of the stereo mix, have someone else do the switching, etc. Ask Doc, we did some cool listening last year- put one of every Klipsch speaker I own along one wall in the living room.

M

[popbumper]

...I believe one of the "best" measures of a perceived improvement is when someone else, unsolicited, makes a positive comment as well. I was out of town this weekend, and while speaking with the wife, she commented how she and my son had watched a movie - and remarked on many positive attributes of the "new speakers". Being unsolicited, I was thrilled to hear her approval, since she is a diehard Forte fan, and was very wary of my implementation of the Corns.

PS: Jeff, you had "nothing" to do with my experience []. Ah, nevermind, your system KICKS!

Chris

[chops]

Did I hear my name mentioned?! LOL

Yes, I went the route of the 511B/902-8B combo on top of my Corns. Sounds mighty fine, too!

However, I have to say, the biggest improvement was moving to active filtering and biamping.

One more thing, I finally got around to buying and installing a near mint 902-8T driver for my center channel from Todd White over on the Altec User Board. Obviously, this driver hasn't seen the abuse like my current drivers apparently have in the past since it has no problems reaching up to nearly 20kHz and have not developed the "work-hardened" diaphrams of my 8B's. So when I get around to swapping out the old and tired diaphrams in my 8B's, I'll most likely be selling my DEQ-1024.