Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83 based; site hound.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!hound!rfg From: rfg@hound.UUCP (R.GRANTGES) Newsgroups: net.audio Subject: Re: cables and ground loops Message-ID: <1270@hound.UUCP> Date: Wed, 24-Jul-85 09:10:33 EDT Article-I.D.: hound.1270 Posted: Wed Jul 24 09:10:33 1985 Date-Received: Thu, 25-Jul-85 22:00:05 EDT References: <379@ucdavis.UUCP> Distribution: net Organization: AT&T Bell Labs, Holmdel NJ Lines: 39 [] It's very easy to do it yourself and all you risk is one audio patch cord (even I can afford that). To see if this is your problem, take one of the interconnecting shielded cables (the one which when you connect it, the amp hums). Examine the area where the connector joins the cable at the end away from the amp (the other end, the preamp end). With a razor or other sharp object carefully cut away the outside cover the shield wire, leaving unsisturbed the inner conductor and the insulating material aroundit. You may wish to wrap the operation site with some insulating tape to keep the shield from unraveling further and provide some more mechanical protection. Now plug the cable back in. If the hum stops you have your answer. I will try to draw the cable as it should look when you are finished: - ----------------------------------------- / \ ooooo--------------------------------------------oooooo \ / - ----------------------------------------- ^ Shield interrupted here Preamp end of cable Amp end of cable What perhaps you should do is treat both cables from amp to preamp this way and provide a seperate ground wire return path via a fairly heavy wire. Real purists will make all interconnects this way - single ground wire. Big danger is that if that ground wire should come loose, you have one fine lot of hum from your speakers (just before they vaporize). Good luck! Dick Grantges hound!rfg -- "It's the thought, if any, that counts!" Dick Grantges hound!rfg