Can I use a Fender Bassman amp as a sub woofer for my P.A. system. I use two powered JBL EON10 G2 speakers. Thanks!

No.

If u mean a 4x10 bass man tweed guitar amp then absolutley not please dont do that!

If you are talking about one of the bass amps well then the answer is not strictly no. though prob more trouble than u are willing to go through)

(the best way to use your bassman speaker) is to not turn the amp on at all and route the signal from your power amp into a low pass filter u build yourself and into the subwoofer, being careful not to exeede the wattage hadnling of your speaker

you cant run a high wattage power am signal into the bassman preamp (it will fry it) however you could send an effects level signal into the amp somehow and use the bassman power section to amplify it (u are going to want to input a signal that has been eq for bass frequencies) this will insure that u do not damage your speaker.
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