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Hi Folks. This is my first post here and I have a question and I already know I dont have enough information. We have a Rogers organ (Circa mid 70's) at our church that has a klipsch speaker connected to the Great Diapason output. The only part number I have is LSBB which I guess covers a lot. There are 2 horns on the top of the speaker the second the width of the speaker the other much smaller at the top. Im not getting any output from the bottom of the speaker below the larger horn in behind what looks like the wooden baffles. We;ve changed amps but not the crossover module on the right at the back to no avail. My question is how to get at this bottom speaker if theres an easy way.

many thanks in advance Will

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It sounds like he cabinet is a La Scala.

It might be easier to first double check that the wire from the crossover to the woofer cabinet is intact. If so, remove the wire from the crossover and do the following. 1) very briefly (1/2 second) connect a small battery (AA or D) to the woofer. Do you then hear "thump"?. 2) test the resistance across the woofer (from this same wire) pair and see if it measures as a few Ohms or is it "open" (someone will surely have a voltmeter laying around)?

Let us know what you discover.

Good Luck,

-Tom

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Guest David H

It sounds like he cabinet is a La Scala.

It might be easier to first double check that the wire from the crossover to the woofer cabinet is intact. If so, remove the wire from the crossover and do the following. 1) very briefly (1/2 second) connect a small battery (AA or D) to the woofer. Do you then hear "thump"?. 2) test the resistance across the woofer (from this same wire) pair and see if it measures as a few Ohms or is it "open" (someone will surely have a voltmeter laying around)?

Let us know what you discover.

Good Luck,

-Tom

Could not have said it better, however if you need to access the woofer that is done from the bottom. You will have to flip the speaker over, and remove the woofer access pannel.

Good luck.

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LSBB= La Scala Bass Bin

*Edit or is it:La Scala/Birch/Black? (just when I think I know something!)

I'm just guessing here, but as it has a sepperate designation, it is a industrial model.

Therefore, there should be 2 fuses in the crossover/jack plate where the organ plugs into it.

Check these to see if they are blown, should be a 1.5 amp for HF, 3 amp for LF.

If there are fuses, should be the 3 amp LF that needs replacing.

If that's not doing the trick, the "doghouse" door that provides access to the woofer is on the bottom of the bin.

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The old LaScala used in a Rogers organ system frequently had access for the woofer from the top of the cabinet.

Look for a removable bottom, if not there, then remove the top, the midrange horn, and all else in the way. Now remove the door to the woofer compartment.

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Don't start pulling it out till you verify it's bad. Find the wire that comes out of the lower section. Follow it to the crossover, loosen one of the screws a little, pull the wire off and test for resistance between the two wires. There should be continuity and about 4 Ohms resistance. If it's open, no continuity, there's likely a problem with the big woofer in the bottom section. There are replacements available at a very reasonable cost.

Try it, come back and tell us what you found..

Will, where are you located?

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  • 2 weeks later...

Many Many thanks for all the replies. Sorry for not getting back sooner but tonight is my first chance back to look at it. The hatch cover came off the bottom and with a 9V battery I checked the speaker OK. The 3 and 5 amp fuses are in the amp and its been checked . The crossover board has been removed and is off for testing at local repair guy. Based on the age Im going to suggest that all the capacitors be changed. One is 24Uf. I was getting output from the horn and tweeter but not woofer when the organ is played. Im really hoping that theres something in this crossover that kills the output to the woofer. After all theres nothing left to check. Thaanks a bunch guys. Ill keep you informed.

will

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Will,

The signal to the woofer goes through the bobbin wound inductor. this is normally a vertically standing inductor, looks like a coil of copper wire. This part is not usually a source of problems but if the circuit is open there will no sound from the woofer.

The crossovers should be labeled on a metal plate, possibly will have a "AA" on them. What do you see?

The serial number was on a printed label glued to the back. Can you see that? The serial number is often stamped into the wood on the back edge of the top panel, can you see it there?

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