Jay,

I have 78 stock khorns with the standard ALK xover.

I think diaphrams either work or don't work, so I don't know I'd mess around with replacing them.

What I have found that made the most difference with my speakers:

1. Good seal in the corners. The split pipe wrap along the edges in the back of the cabinet made a big difference. The pipe wrap and staple gun took about 30 minutes. Pushed them into the corner as tight as I could get them.

2. Since I had the ALK xovers I bi-wired the speakers. Gave me more "air".YMMV

3. Accoustic treatment. I just added foam panels on the wall between the speakers and some on the ceiling.

My next upgrade will be to replace all the original speaker wire, but this is way down on my list.

You do have a killer system and I hope it works out for you.

Danny

I do not have Khorns but do have La Scala's.

For me, the biggest change was swapping the stock AL's for ALK universals. This was a dramatic change and really opened up the speakers. Much more clarity and detail, more air around the instruments, etc. Basically, they removed the blanket from the speakers and let them breathe. Next in line is the Altec 511B's still using the stock K55's. This was a significant improvement as well, again with more clarity and detail in the midrange, and painting a much larger soundstage. It also moved the soundstage up the wall a couple of feet. I have been told the Trachorns are even better, but have not heard them. And lastly upgrading to the BEC tweeters. I know some here do not like them, but to my ears they were cleaner and clearer, and provided more detail in the upper regions. YMMV...

Mike

Just having Bob Crites update the caps in the xovers to original specs was amazing.  Before that, the high end was dull and lifeless.  After, it was like draining water out of your ears after swimming.  Night and day new high-end.  Crisp.

Danny thanks for the support like you I have the pipe foam and a good seal, also the ALK's. I have long ago replaced the original wire to all copper. I may need to address the acoustic issues for some improvment as you did.

Jay

Mike Lindsey:

I do not have Khorns but do have La Scala's.

For me, the biggest change was swapping the stock AL's for ALK universals. This was a dramatic change and really opened up the speakers. Much more clarity and detail, more air around the instruments, etc. Basically, they removed the blanket from the speakers and let them breathe. Next in line is the Altec 511B's still using the stock K55's. This was a significant improvement as well, again with more clarity and detail in the midrange, and painting a much larger soundstage. It also moved the soundstage up the wall a couple of feet. I have been told the Trachorns are even better, but have not heard them. And lastly upgrading to the BEC tweeters. I know some here do not like them, but to my ears they were cleaner and clearer, and provided more detail in the upper regions. YMMV...

Mike

Mike thanks for posting and giving me your upgrade path, I thought about the 511B's as well but want to keep everything inside the stock enclosure. The Trachorns were a thought too, but I am still undecided on that.

Jay

Well guys after a closer review of my speakers I feel I can wait for an upgrade, If I choose to do it at all turns out my speakers are sounding better than I thought. Must have been a combo of the source material/ and the way I was feeling that day. In fact if they never sound any better than they do right now, it  will be ok. I do thank all for the advice just the same, now I have the info if I decide to upgrade.

 Jay