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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Jim McKeveny on July 07, 2017, 07:18:27 AM
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A client replaced some aged cones in EAW SB850F. OEMs were EAW rebadged RCF L18P300. New cones are RCF L18P300. New cones pop and unload and are essentially unusable in the box. RCF apparently changed key parameters on the device (including frame) somewhere along the line, while retaining the same part number.
How to remedy?
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A client replaced some aged cones in EAW SB850F. OEMs were EAW rebadged RCF L18P300. New cones are RCF L18P300. New cones pop and unload and are essentially unusable in the box. RCF apparently changed key parameters on the device (including frame) somewhere along the line, while retaining the same part number.
How to remedy?
May be wrong, but didn't the SB850 use L18P200's? FWIW the SB1000 used the L18P300.
http://www.usspeaker.com/rcf%20-%20L18P200n-1.htm
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May be wrong, but didn't the SB850 use L18P200's? FWIW the SB1000 used the L18P300.
http://www.usspeaker.com/rcf%20-%20L18P200n-1.htm
Peter, All of my SB850s use the L18P300/L18400. I did have one that had an 1800 watt speaker in it, but it was not one of the original speaker to that cabinet.
The SB1000 do also use the L18P300/L18P400.
Bill
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Peter, All of my SB850s use the L18P300/L18400. I did have one that had an 1800 watt speaker in it, but it was not one of the original speaker to that cabinet.
The SB1000 do also use the L18P300/L18P400.
Bill
I don't doubt you, but FWIW all the ones I have seen were the ribbed cone / L18P200 - I think there were two different frames with the P 200 - Parts Express reference the shallow version as the replacement https://www.parts-express.com/rcf-l18p200-n-18-woofer-speaker--294-880
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A client replaced some aged cones in EAW SB850F. New cones pop and unload and are essentially unusable in the box.
The client wired the drivers out of polarity with each other, with dual driver enclosures both drivers must move in and out in unison. These aren't junk drivers and will perform more or less as expected in just about any reflex enclosure as long as somebody doesn't botch the intall. Use the 9v battery test to visually see what driver is incorrectly connected and correct it.
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The client wired the drivers out of polarity with each other, with dual driver enclosures both drivers must move in and out in unison. These aren't junk drivers and will perform more or less as expected in just about any reflex enclosure as long as somebody doesn't botch the intall. Use the 9v battery test to visually see what driver is incorrectly connected and correct it.
This is what I was thinking...
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Original SB
850 (shallow with rear wheels) did indeed use p200's. These are the fullsize 850 companion flying boxes with the steel rear counterweight.
Wiring has been tested and inspected and is correct. New cones exhibit same behavior even with only a single chamber under test.
What has been determined is that RCF at some point introduced a new speaker with new parameters, yet inexplicably kept the P300 designation. It is simply not a drop-in replacement for earlier P300's.