Dave A

I do have an idea for the back side of a La Scala but not quite that large. Wonder what a 1/2" aluminum plate La Scala would be like?

You can make those Sonicaps fit on there and replacing those old caps is one of the very best things you can do.

Just slow today I guess and sometimes the obvious just eludes me.

Actually I do like A7's and they are one of the very few speakers that are not Klipsch I will work on. I was just hoping to get recommendations on what to do to make them be their very best full frontal audio experience. I have to admit to being a bit confused though by your audiophile comment. I though you had stated elsewhere that those A7's were the very best thing out there and that is why you had a set of them and now you are saying they are not audiophile grade quality. Are you telling me not to bother fixing these up?

I took a rubber mallet and started tapping to see where the sound might come from. By ear it was hard to see where and I will buy a stethascope if this happens again before trying to find the rattle. The howl from this was most prominent from the bass bin while being played but the top section had the rattle when tapped on. Eventually I put my hand on the tweeter by accident and there they were loose. New tweeters were not in consideration at all but you can bet I will double check from now on. Me too even if it is a bit embarrassing.

I don't know Jim, I like Monty Python too although my wife thinks it is a complete waste of time. Far Side is another one and absurd things just entertain me I guess. It's like John Cleese was here and writing the Ministry of Silly Wires.

I have three of those on my storage rack ready for rebuilding. What would you recommend I do for the best possible sound?

How, I am amused that this tread is still going on like this with no reference to the original post.If a moderator wants to close it that have at it. Oh yes comedy gold and no one has to tune in here since they know what is going on. Admit it MookieStl you could not sit down and be this creative and there is a form of literary genius at work here.

OK the old OEM coil measure very close so is there an advantage to replacing it with a new one? I figure these are not like caps that go bad.

OK here is my stupid speaker guy story. Turns out that when you put a nice shiny new set of those great MAHL tweeters in a La Scala that you ought to remember to tighten the clamp plate to the lens body. Finger tight does not work real well and when the start loosening it gets real interesting. As I hang my head in shame and slink off tonight thinking you just never know the limit to bone headed things that can be done. The flip side to the story is that braces work and I will post pictures of quick and easy later this week.

As I replied to John I have also used a brand new Kappa 15c and same thing. I will be back on this thread when I have an answer as we are all guessing and there will be an answer. I can't rule out something simple I am overlooking but what it is is not apparent yet. I do appreciate some of the tips which I have tried or will soon try.

I had no idea this fount of wisdom was at it again but now I am compelled to go through it all later today. I am going to put down the current science fiction read which has a finite end already and spend a bit of time on this thread which is in active creation. How often do you get to see fiction created right before your eyes outside of mainstream network news? I bet Bill Nye says capacitors work just like our resident guru does and two brilliant scientific minds can't be wrong.

Hmmm you forget some operate on a much higher level of logic and it surpasses what we can understand. It has to be self learned and only one on this forum has achieved this ability to not hear but still hear.

Smaller and that one looks smaller than the ones I have seen in the La Scalas from the 80's and 70's. It looks more like a true equal leg triangle.

Great to read about you getting these MWM's. ONE of those Crown xli800's was enough to run my three way stacks with OEM crossovers louder than I could listen to without hearing protection.

What it means is that from the factory it is maybe 1/3 as big as normal. I have been in the guts of many of these and I have never seen anything like this before. No it has not been replaced there are no signs of glue or stuck remnants of larger pieces of wood removed and the little bitty put in place. Guys look I don't understand why there is even a question as to whether it is way small or not. As many of these as I have been into I am telling you it is and that ought to be sufficient. When I have time to fiddle with this again I will get a picture and until then you just have to decide I know what I am describing or I just cant see what is in front of me. I have pondered doing this very thing and it would be the easiest quick way forward. It is very tight though and might be impossible to do without removing one side. I am leaning towards forgetting this problem for now and dealing with it when I have time to do a rebuild of the cabinet with 1" sidewalls. closest things and it reminds me of taking an orbital sander and going to the front of the sidewall and that lovely resonance you get then. K-55-M is not the problem as K-55-V's do it too an easy quick test done tonight.

Well I did the ear test and sticking my ear in the mid horn A-OK but the bass bin was another story. When I say mid range I mis-spoke since what I should have said was the top end of the woofer output in the bass bin. Yes I have one and there is also a free one inside of Audacity. I have done that before I just didn't remember to do it here. Yes a new Eminence Kappa 15C and an old known good k-43 and both did it. Funny thing is with room EQ using a Driverack Pro you can almost make it go away.

Well I know where a set of K-402 sitting on top of four single MWM bins are and you could use the 456 for center channel 🤨

I assume from what the OP said that this happens with two different amps hooked up at the same time.

I have two Crown xli800's. Great amps but the output between the two is clearly different and after I set these up with a way to control gain from each to balance output all was well. Lots of those caps in even the better amps have 5 or 10% tolerance so if you go to the extremes at each end it still passes manufacturer tolerance but can be up to 20% different worst case scenario. Good comments as all these things can come into play but I figure the most likely culprit is two different amps.

It is mid range for sure. Nope it is serious resonance and not something like that and on both of them.

I will have to get a picture of these to post. They are so small they might as well not be there. I can see the sound waves hitting that back side and ricocheting their way out to the sides and getting garbled on the way out. It is a weird problem and I wish someone with deep acoustic design knowledge would chime in here with the precise effects splitters create. One thing I am pretty sure of though is there was a lot of time spent figuring out the right splitter size and the ones I have seen have all been pretty consistent until this one.

Well yes that is exactly what I have been saying and they both have itsy bitsy tiny splitters. So I am back to reminding everyone that I am primarily asking about what effect these runt sized splitters can have. They are sequential numbers so someone decided to do a wonderful different thing on these. I suppose the idea of nails splitting plys is possible but two in a row? I have eliminated everything you can come up with except the idea of internal doghouse bracing which I don't think will solve this problem. The more I read the responses and think about all this the more I believe the splitters are the culprit. When I have time I will solve this splitter problem and report back.

Can I take a small hammer and tap along all the joints and detect this separation?

I am a practical guy and so my first effort is to find out what is different that would cause this in construction of the cabinet. If everything was the same top to bottom in the cabinet build compared to others I have worked on then I would have to try what you are suggesting I guess. But there is one big difference and it is the splitter so I am asking for specific information on this topic before I start off into other areas.