Troubleshooting La Scala II

[OldCrow]

This is the longest thread I have ever posted anywhere! It's for a good cause, but I have no experience with La Scalas.

    Last week I met a young married couple who had recently inherited her father's system. La Scala IIs (logo in upper grill corner), RP 600M II bookshelf speakers, Macintosh MC402, Adcom GFA 575es amps, Parasound Halo P5, Adcom GFP 750 preamps, SVS SB 16 subwoofer, and a Yamaha CD player. She's keeping the Parasound, Adcom amp, and the small speakers. The rest is for sale. I've been an audiophile for 40 years and never seen a stack of equipment like this outside of a showroom! My core system is Polk Audio SDA SRS speakers with Carver M1.5t, Crimson 275 amps, Parasound and 10 Octave preamps. She lived nearby and I wanted to hear the LaScalas for possible purchase.

    Now comes the problem. They sounded terrible- boomy, underwater bass burying weak mids and highs. I heard a set of K horns in the 70s, but had no real experience with horns. I have read extensively about Klipsch and "their sound," but this was definitely not right. She had a friend help her hook it up. She said it sounded nothing like she remembered. I had hoped it was a simple wiring problem, but the friend had hooked it up correctly. Also, there were XLR connectors, balanced/unbalanced and stereo/bridged toggles, and the Parasound had crossover controls for the subwoofer (which had already sold). I checked the jumpers on the speaker back, and the upper/lower section connection. I tried all combinations of equipment, even brought over a basic Kenwood receiver and another CD player. Always the same.

    Both speakers sound exactly the same. I took off the jumpers and ran the uppers and lowers alone. Even though the sound is terrible, there is a center image and I can hear stereo imaging. It sounds like all the drivers are firing, it just sounds bad. I can't imagine the same problem in both speakers. I've never had any experience with blown drivers, but that's what was coming to mind.

    Then she said she also had some parts (see pics). She didn't know what they were for. Two look like tweeters and two I didn't recognize. On this forum, I read a 2018 post by member Panelhead recommending replacement of blown tweeters with B&C DE-120s. Those were the tweeters she had! Great thanks to Panelhead- he supplied my first breadcrumb! Now I'm guessing her father had problems and had ordered some parts. So now we have two tweeters and will try swaptronics. Does anyone recognize the other two round pieces? I watched a YouTube of someone dismantling an AL5 and he unscrewed the mid-range driver. Was there a different type on the IIs? 

    This has become a bug under my skin. I really want to help this couple fix their speakers. I have visited them twice but have not removed the back panel from the speakers. I'm a retired Air Force electrical engineer and no stranger to troubleshooting. I've seen some threads about checking signal path with a multimeter.

    In closing, does anyone recognize the round device with four screws on it? Also, what would be the next step after swaptronics? Thanks for your time.

[billybob]

Yes welcome back.

The only thing not mentioned is the crossover Network. 

Sure the folk can help you with the situation.

[pbphoto]

Do you have any pics of the entire speakers?  La Scala 2's don't say that on the front grill - they just have the standard klipsch logo. On the back of the speakers, there will be a klipsch tag that says LS2 with serial numbers.  If that isn't there, then maybe you are dealing an upgrade science project.

[OldCrow]

Thanks for quick responses guys. I think we're talking about La Scala II Heritage models. The grills are screwed on from the back. If something did indeed get scorched, the crossover could be damaged as well. But it seems like the father went as far as to purchase some pieces. I'm pretty confident about identifying the tweeters (Panelhead comment). Do either of you recognize the other round object?

[billybob]

That last round object looks like a speaker diaphragm.

Turn it over and snap a pic if you will.

[billybob]

And may as well snap pic of crossover. Thanks!

[Schu]

LSii grills are DEFINITELY removable OP...

 

 

 

Your XO's should look like this AL4... on the bottom

 

[OldCrow]

There are top and bottom pictures of the item above. The top has four bolts and a lens like center. The bottom is smooth metal with a dimple in the middle. I have not taken the back off to see the crossover yet. They aren't my speakers and I don't want to weird out the nice couple. I visited once to audition the speakers and once to begin troubleshooting. Audio enthusiasts are quick to help each other out, just like this forum. I've gotten three or four replies in 20 minutes already. Regular folks might just think you're being nosy.

[Schu]

1 minute ago, OldCrow said:

There are top and bottom pictures of the item above. The top has four bolts and a lens like center. The bottom is smooth metal with a dimple in the middle.

That Dimple is called a Phase Plug...

 

how sure are you that the issue is the speakers and not the source?

[OldCrow]

Billy Bob thinks the item is a speaker diaphragm. Schu identified the dimple as a phase plug. Is it a speaker diaphragm and which driver would it be associated with? 

[Schu]

what the heck are these?

 

[OldCrow]

Sorry Schu, I missed your source question. As outlined at the top, there were two amps and two preamps. There were XLR and RCA connectors. There were bal/unbalanced and bridged/stereo toggles. There were subwoofer crossover controls on the Parasound preamp. I googled the owner's manuals to ensure all the switch settings were correct. I even brought a Kenwood receiver and another CD player for a minimalist set up. I also drove an hour to a Klipsch showroom to hear what they should sound like. Magnificent! The dealer indicated even with run of the mill equipment, they should sound pretty good. Also, the bookshelf Klipsch sound great with the equipment. So I'm relatively confident it's the speakers.

[OldCrow]

Schu "what the heck are these?"

 

That's what I'm trying to figure out. In the first post, there are four pictures. The top two are tweeters and the bottom two are the item in question.

[OO1]

32 minutes ago, OldCrow said:

 . So I'm relatively confident it's the speakers.

the original tweeters for  the Lascala II are  the K-77 F ,  klipsch Part  # 127126  ,replacing  defective diaphragms does  not require soldering   ,

  klipsch  -800-554-7724 

https://support.klipsch.com/hc/en-us/requests/new

 

 

[OldCrow]

001- thanks for the reply, very informative. Do you by any chance recognize the two items pictured at the top of the post? I'm pretty sure one is a tweeter. Billy Bob thinks the round item might be a speaker diaphragm. Schu identified The dimple in the round item as a phase plug. But I still don't know what the item is or which speaker it's associated with.

    There's also a possibility that it's unrelated to the speakers entirely and just an odd piece of hardware that her father had.

[Islander]

Those are La Scala IIs, which first came out in 2006, barely last month in Heritage Series time.  Normally, they wouldn't need any service or maintenance for 20 to 30 years, so it surprises me that those speakers have any problems.  I've got a pair of 2007 models, and they're still like new.

[Marvel]

My two cents... it sounds like the crossover may have been bypassed to use an active crossover of some sort.

 

If just trying to get the LSII cabinets working correctly, I would make sure the LSII  crossovers are hooked up correctly.

 

A power amp should have leads going to the crossover and from there, six wires. A pair for the woofer, midrange horn/driver and tweeter horn/driver. Repeat for the other speaker (left or right).

[OldCrow]

 

Islander- thanks for verifying the speaker model. Seems if you say La Scala, they could be new, 60 years old, or anywhere in between. You're right, this shouldn't be an age problem, I think something happened to them.

 

Marvel- good point. I hadn't considered Frankenspeakers. The screw heads on the back seem untouched, but I'll definitely have a look at the crossovers. Thanks.

[babadono]

@OldCrow The item in the first two pictures of the first post are Crites CT125s which are a drop in replacement for Kipsch k77 tweeters. The B and C driver will take much more power/punishment without opening the voicecoil (burning out). Are you sure the tweeters that are currently in the speakers are working? 3 way speakers in which the tweeters are not functioning sound BAD.

I can only speculate on the second item ,looks like a midrange horn driver? But is it the correct one for a LSII?

[OO1]

13 hours ago, OldCrow said:

OO1  - thanks for the reply, very informative. Do you by any chance recognize the two items pictured at the top of the post? I'm pretty sure one is a tweeter.  

  @OldCrowthe tweeters in the 1st and 2nd  pictures are aftermarket CT12O  , the  klipsch  original K-77F  tweeters may have been removed or the wires are simply disconnected , to determine if the diaphragms are defective  , you'll need an Ohmmeter   . 

 

the 3rd and 4th pictures are klipsch tweeters for a  different   klipsch speaker model