Cornwall midrange udgrade needed

[DucatiDave]

I’m new to the forum and I’m really enjoying my journey into vintage stereos. I have a Sansui 1000a tube receiver that I am currently in the process of restoring. In the meantime I am running my speakers with a Yamaha htr-5630 receiver, 70 watts per channel.

I have a set of original large advents that I re-foamed, and I understand why they were such a popular speaker. They sound great to my ears. I listen to a ton of live Greatful Dead and the advents have great bass while still sounding very open and clear on the top end.

Now in all of my reading on vintage equipment, MANY people rave about the combination of vintage klipsch with tube amps or receivers because the tubes help to soften the sometimes overpowering horn mids and tweeters. Since I have the Sansui tube setup and I like good strong bass, I set my sights on the Cornwall. I found a really nice set of Cornwall’s and hooked them up to my Yamaha. I was fully expecting to have to turn the treble down due to the horns and the fact that the Yamaha is solid state and fairly bright. Well, just the opposite happened. I had to crank the treble and lower the bass just to get a sound somewhat close to the advents. I’m pretty disappointed to say the least, I like the advents so much better than the Cornwall’s right now. I really want to love the Cornwall’s.

I have looked at Bob Crites website and he describes exactly what I hear. Great bass, but the top end is lacking and not as open as I would like. Hence why he came up with the cornscala. My Cornwall’s have had some mods, bought this way, here is the current setup. Crites tweeters, stock k600 horn with k-55v driver, and the k-33e woofer. They are from 1978, with the type b crossover. They were recapped with a Crites kit in 2008. So what can be done to upgrade the midrange? I’m assuming the Crites tweeter is just fine and should be left alone. Is it something as simple as replacing the k-600 horn with something larger? I know the LaScala’s used the same k-55v driver. I am pushing my luck with the sheer size of these speakers (wife is not pleased). So I need to stay with the stock cabinet size. Maybe a horn from a forte or chorus?

Any help would be greatly appreciated. I fear that once my Sansui is done and I hook up the Cornwall’s, the midrange and top end will be so softened by the tubes that I won’t be happy.

Thanks
Dave

 

[Jirachi]

You could always try to find a pair of Chorus i/ii. They have a different mid range horn. There is a titanium midrange diaphragm available but I don't know much about it. Might be what you are searching, might not be.

 

[longdrive03]

Yo Dave, depends how far you want to go and how much you want to spend like most things in life!!!

Bob Crites (I'm 45 minutes down the road from his place) has the John Allen A-55 which is supposed to be much better than the K-55. Haven't heard it myself but Bob tells me it is much better.

If you are a handyman guy you can replace the K- 600 C horn with another brand. I've don't this twice on rebuilds of C's using the Parts Express 8 x 12" horn (it's like $10). This horn has a bolt on connection but you can mate a screw on adapter to it as I did. You can cut the larger horn opening necessary easily given the distance between the mid horn and woofer cutouts. Here's two pics of a Cornwall I redid for a friend using this technique. Heck while you're at it veneer the fronts, sides and tops with cherry veneer!!

 

[longdrive03]

Here is the link to the PE horn I used. $7 each - don't let that fool you it is heavy thick plastic.

https://www.parts-express.com/dayton-audio-h812-1-exponential-horn-100x60-2-bolt--270-304

 

[macaltec]

Just for giggles, I would try a different amp/receiver, preferably a 2 channel. I was less than impressed with my second set of Cornwalls when using my HT receiver.

 

[BilboBaggins]

Just for giggles, I would try a different amp/receiver, preferably a 2 channel. I was less than impressed with my second set of Cornwalls when using my HT receiver.

I was thinking the same thing. Mine are being driven by a 200wpc McIntosh MC2205 and they sound really really good. For an experiment on the weekend, I plugged them into my freshly leestereo restored MA6200 and it was lacking. Sounded good, but the magic was gone, especially in the bass.

 

[DucatiDave]

I’m starting to think that the Yamaha is the problem. I can get them to sound better if I max out the treble, level 10 plus 3db boost, and back the bass down to a 4 or 6. Even at those levels the top end is not overpowering at all. I’m going to wait to make any changes until I have my Sansui 1000a up and running. If they are still lacking then I will look into larger midrange horns. I will say this however, I know I am not the first person to make this sort of an observation about Cornwall’s. Otherwise there would not be a market for the Cornscala.

 

[SiliconTi]

Hmmm... Mine use the plastic horn mid hooked up to a Mac 4100 and sound great.

I agree, try a different amp.

 

[Coytee]

I know I am not the first person to make this sort of an observation about Cornwall’s. Otherwise there would not be a market for the Cornscala.

As I understand, the Cornscala was originally designed to use the bottom end of the Cornwall and the midrange of the LaScala. Obviously there are other flavors out there now but as I understand it, that's what got the ball rolling.

If I can try to repeat what Al K said about that situation.... (and this is paraphrased since I don't recall the exact)

"they took the worst part of the cornwall (higher distortion direct radiator woofer) and mated it with the worst part of the LaScala (K400)"

(seems Al wasn't a big fan of the base design)

Many people have found that upgrading from the K400/401 can bring them some improvements.

Not knowing what your budget it...and if you decide you'd like to change things out... AND, if you want to "keep it Klipsch", you might consider looking at their K510 which is a 2" throat horn. It would set on TOP of your speaker unless you wanted to reconfigure things. Might need an active. But....it would then take it to a 2-way speaker which alone, would greatly increase the intelligibility of the speaker and the "scale" of sound would grow.

The K510 though not cheap, is a good sounding horn and keeps things 100% Klipsch.

Having heard them (and own one) the larger format horns will be a major improvement over the smaller horns.

 

[fernarias]

It could be your amp since modern amps don't put out their rated output on some hard to drive (and this is different from efficiency) speakers with 15 in woofers (that's was my impression when using a modern denon at 100 watts, lol, per channel). It could be the midrange drivers (or tweeters) are no longer working as they should and they need to be rebuilt or replaced. You should determine that by checking the drivers or using another amp (I vote vintage). Then we can talk about upgrades since a stock cornwall sounds really good when operationg correctly and being are being driven by a good amp (the higher the watts the better).
Mine sounded great when I demoed them on a Pioneer 1280 and didn't sound great at home until I bought a vintage amp to go with them(that sansui 1000 would do it).

 

[hatrack71]

When I was playing with my Cornwalls, I disconnected the midranges and used Altec 511 horns on top with 802-8G drivers. I never though the stock Klipsch midrange horns or drivers were anywhere near large enough to play clean at the lowest frequencies of their stated ranges. The Altecs are a massive improvement there and they still are only 1". They actually blended nicely with the K77 tweeters. Definitely no longer a Klipsch at that point though. But the Altec horns/drivers are much less fatiguing and seem less beemy with wider dispersion. Once you hear a really big horn (large format drivers) do the lower frequencies effortlessly- 300-500Hz, it makes the inadequacies of a smaller horn all too obvious. And really, even a 1" Altec w/ a 511 horn should be crossed no lower than 800hz and an 811 horn at 1200Hz or slightly higher. I experimented with this for several years with an electronic out board crossover and bi/tri amping.

With the Cornwall it might be best to modify the crossover and of course keep them stock looking. I'd change the crossover frequency to 1200hz...possibly 1500Hz for the midrange horn and let the K-33 take up the slack. You'll hear an improvement in clarity and your ability to listen longer without getting fatigued. My advice to anyone running an old horn system is get an electronic crossover and bi/tri amp. Craft the sound the way YOU want it to sound.

 

[twiiii]

Way Back when 70's are Klipsch rep and been a JBL rep. He took an Altec adapter plate an attached a JBL driver to his Corner horns. He thought the phenolic diaphragm of the Atlas drivers were just to slow. Of course he had to change the crossover a touch and re connect the step down auto former. I met friends of his at a Wces show and they all said they were the best pair of Cornerhorns they ever heard. I am not saying you need to go that far, but the horn technology of a Cornwall is very old and maybe you do need a new horn and appropriate driver with an updated CROSSOVER.

 

[20Hz]

I'm with those saying try a new amp. My Cornwalls (1979) sound amazing. I had a Rogue cronos magnum (100w/side) and now a SLI80, but I tried them out with my Sansui Au-505 (30w/side) when I bought them and they sounded wonderful. They don't lack in mid/high frequencies. Have you opened them to make sure the connections are all solid?

 

[DucatiDave]

I am now powering them with a Sansui Seven. Deoxit all the pots and switches, sounds amazing with my advents. Cornwalls are still lacking. I have midrange cranked, treble one away from top, and bass at halfway or flat just to get the mids and highs sounding stronger. All connections are good, drivers all ohm out properly and they are putting out sound...just not enough for my ears and taste. Crossovers recapped in 2008 with sonicaps.

I’m not saying they lack in mid or high frequencies, they lack in how those frequencies are transmitted. There is no mid and high presence. The bass overwhelms everything else. It sounds like they are in a giant concert hall, or when you turn up the reverb on an old fender guitar amp. Just kind of a hollow feeling.

I’m the kind of listener that would probably favor LaScalas or the Cornscala. There’s a reason Bob Crites came up with the Cornscala. They have bass for days. I can shake the whole house down if I wanted. These might not be the speakers for me that’s all.

 

[20Hz]

weird. But yes, speakers are very personal (much like motorcylces ). I just sold some ESS AMT 3s which people rave about but in my house with my front end the Cornwalls wiped the floor with them.

 

[fernarias]

I am now powering them with a Sansui Seven. Deoxit all the pots and switches, sounds amazing with my advents. Cornwalls are still lacking. I have midrange cranked, treble one away from top, and bass at halfway or flat just to get the mids and highs sounding stronger. All connections are good, drivers all ohm out properly and they are putting out sound...just not enough for my ears and taste. Crossovers recapped in 2008 with sonicaps.

I’m not saying they lack in mid or high frequencies, they lack in how those frequencies are transmitted. There is no mid and high presence. The bass overwhelms everything else. It sounds like they are in a giant concert hall, or when you turn up the reverb on an old fender guitar amp. Just kind of a hollow feeling.

I’m the kind of listener that would probably favor LaScalas or the Cornscala. There’s a reason Bob Crites came up with the Cornscala. They have bass for days. I can shake the whole house down if I wanted. These might not be the speakers for me that’s all.

Not at all like how a cornwall sounds. Even the frequency response on a cornwall is pretty flat (as published by Klipsch). If you think it's your personal tastes have someone else listen to them flat (bass, treble at 0). I personally suspect that either the mids or tweets are out of spec as I've said. It's been my experience that bass doesn't kick in until high volume (or high wattage). Of course it could be that Cornwalls aren't for you, as you said. That's fine too, we all have our own tastes. For me Fortes are the best (having compared the entire Klispch line in 1985 when my ears were excellent as I was only 19).

 

[NeonDriver]

You could try inverting the polarity of the mid and/or tweeter. A hollow sound seems like it could be a polarity issue. I would start with the midrange. Whoever recapped them in the past may have swapped the polarity to compensate for room issues or for their personal preference.

 

[crouse]

How far do you sit from the Cornwalls?

 

[DucatiDave]

Well boys, I’ll be dipped in shi$!! I got my Sansui 1000a tube model recapped and fired up today. The Cornwall’s sound like a completely different speaker with the tube receiver. The top end has opened up a lot. I’m playing with the loudness and presence settings in conjunction with the bass and treble. But right off the bat I knew something was different. I just cant believe the difference tube makes versus solid state. And I wasn’t using a POS solid state either, I was using a Sansui Seven and an Eight, TOTL models from the early 70’s. I’m in shock.

 

[delbomberger]

I have 77 Cornwalls. Hooked up to various Vintage Pioneer and Yamaha pieces they sounded great. I thought they were OK with the Home Theatre set-up. I have recently been trying out the latest Outlaw RR2160 2 channel and it sounds superior in every way to the vintage stuff (all of which had been rebuilt). I do think 2 channel is a great way to listen to the Cornwalls.