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Shorting Plugs and Non-shorting Plugs - Wothwhile?

Well, I have a hum that I can't isolate. I've tried all the usual fixes with no luck. I am convinced, however that the problem is interference from some other device (that I can't isolate). I have a bunch of cheap interconnects that I could use for open RCA connectors on my preamp (Tape 1, Tape 2, Tuner, etc.). Is the effort worth it? I certainly don't mind sacrificing a few cheap ICs to the audio gods. If you have an opinion, please weigh in...
licoricepizza
newbee
4,767 posts
 
You don't have much to loose by trying, they can reduce noise from a source external to the pre-amp. And have worked for me. But so has a good power conditioner or a dedicated line. You won't harm anything by shorting out inputs. But, unfortunately sometimes 'hum' is intrinsic to the amp or pre-amp itself (have you listened to the amp itself without anything plugged into it?).
licoricepizza OP
48 posts
 

Actually, no, I haven't listened to the amp alone. I did,however, listen to the preamp alone (with headphones, and everything else unplugged), and I still got the hum. That, for me anyways, rules everything but the preamp. Believe me when I say I've tried just about everything.
bdgregory
1,712 posts
 
The short answer is it is worth the effort IMO, though don't expect magic.

I had some serious background noise some time ago and tried shorting plugs (home made) to try to solve it. I found it helped very little, though did seem to help some. I also found that my problem appeared to be a cumulative effect of bad ground connection (on my TT), connectors in need of cleaning, IC's that needed to be re-routed, and open connectors on my preamp.
rhljazz
1,254 posts
 
Not for your problem. Try disconnecting cable tv line and ground and see if that makes a difference. Have you tried the preamp headphone combo at another location to see if it's still there? Take it to a friends house that doesn't have a humming system. If it hums there, something internal is defective or a poor design.
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