enigmasse

I thought it was a rolloff at 2kHz. See http://www.hometheaterhifi.com/volume_9_2/feature-article-curves-6-2002.html Isn't the X-curve applied to the theater soundtracks? Since these speakers have an x-curve "de-emphasis", I figured it would be hot from 2kHz up so net output would be flat, essentially negating the x-curve. Am I looking at it wrong?

I have a set of KPT-250s that I will use as surrounds in my home theater and they are brighter than I like. I presume this is due to the x-curve de-emphasis that is built into the speaker. Could this be the case? Is replacing the crossover the only way to remove the x-curve?

I received the AA crossover back from Bob Crites last week. He replaced the capacitors and checked everything else. I am pleasantly surprised by his quality workmanship and by the sound difference! It still clearly has a different tone than the Industrials but so far, it isn't too distracting that I am going to do anything about it. Thanks for the crossover advice, well worth the expense. I am glad I didn't go down the diaphragm path or anything else more drastic... I wonder how the AL with new caps would sound! Or moving to a AA altogether. Maybe another day...

Marvel: Did you replace them with AA crossovers? How do you compare the sound differences?

This is going to be a subjective question though I still want to get feedback: How will this center channel LSBR sound in relation to the industrials in a home movie setup (industrial - LSBR - industrial)? Will it sound close enough that the sound would meld together or will I always be able to distinguish the sound from the LSBR as being different? I hope with an AA rebuild, the difference will be tolerable.

I called Bob and after talking to him, I'll have him test the crossover out and give me a synopsis on what it needs. When I pulled the crossover out of the speaker, one of the leads that connected to the 2uF capacitor was disconnected from the plastic spindle (with the brass screw). Not sure how that would affect the sound! Looks like someone at one point tried to solder it poorly. Depending on how the AA sounds, he may just convince me to replace the AL in the industrials to AA too. [^o)] This is getting more expensive than I originally anticipated. [:'(]

I double checked the wiring and it is correct as far as I can tell; picture angle is deceiving. I'll have to research how to rebuild the crossover. I can easily find sites for replacing the caps, but haven't found anything on the inductors yet; still searching. I am sure there are tutorials somewhere. Assuming I get the crossover refreshed, ultimately, how will it compare to the AL network? The industrial La Scalas have a square magnet and say K-77. The LSBR are square too and say K-77M. In this post, http://forums.klipsch.com/forums/p/48970/464148.aspx#464148, Tom states: "AFAIK if it has the square magnet and is a K-77 it is a K-77-M". Can someone confirm this? I checked the K-55v and it has a resistance of 10.7 Ohms...

Here is the AA crossover on the LSBR. I also noticed the LSBR has a K-77-M tweeter while the industrials have the K-77. Is the K-77-M the original driver type for a '79 LSBR?

You're right, I got the back panel off and it has the "AL" crossover. I went ahead and posted a picture. They look clean!

I have a pair of stock '86 industrial La Scalas, having the K-77_, K-55M, K-43 and AK (possibly a AK-3?) crossover. I recently purchased a stock '79 LSBR La Scala for a center channel, having the k-77_, k-55V(push terminals), K-33 and AA crossover. The sound difference is much more than I anticipated. The '79 sounds hot, squawky (like a megaphone), not dynamic and just unnatural sounding like the '86 industrials. Even pink noise sounds lifeless! I am having a hard time meshing the sound with the '86 La Scalas. - I know the idustrial has the newer plastic/resin horn while the LSBR has the metal horn. From what I read, this shouldn't make a difference and dynamating the outside won't help. - Could it be the different cross-over? I know the AA is hotter, however does it make it sound squawky and not as dynamic? I also read that if I replace it with a new crossover from someone on the forum, it would probably sound even hotter with new caps. - Could it be the difference between the K-55V and the K-55M driver? - Could it be a K-55V diaphragm issue? How about the alinco magnet? Can I tell this by measuring the ohms between the two terminals? I am hoping to get ideas on how to match the sound to the industrial La Scalas (prefered) with minimal cost. I didn't expect this much difference, there must be something wrong!