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Ampeg Mono Bridge

I have an Ampeg B4R and I want to mono bridge it. I bought a brand new 4 pole speakon cable but not sure how to rewire to convert to a mono bridge cable. Inside the black outer sleeve there are 4 smaller cables that are black, red, blue, and white. Not sure if this is the correct cable I need or if it's only supposed to be 2 smaller inner cables. This one says NL4FX. Any help would be GREAT appreciated.
 
You actually need a bridged cable (supplied with the amp). This is a 2 conductor cable with 4 pole speakon connectors. You would have to cut back wires to make your cable work. At the amp end ONLY, cut back the wire on the 2+ position (probably white) and move the wire from the 1- (probably black) to the 2+ position. Label that connector for amp end only. A 4 pole two conductor cable would also need to be labeled, but would only need the 1- wire moved to the 2+.

http://www.ampeg.com/pdf/B4R.PDF
 
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You need a cable that is connected +1 +2 at the amp end, make sure you mark the connector for the amp as it won’t work the wrong way around. At the other end it need to be wired +1 and -1. So the cable should connect +1 to +1 and +2 to -1.

Be very careful with your volume level as bridging releases one hell of a lot of power. I’ve been using stereo power amps since the Eighties. I’ve never had the need to bridge any of them. i run mine parallel mono, each channel into one cabinet.