Rotel RB-1092 hum

RE: Rotel RB-1092 hum, posted on April 14, 2015 at 13:33:47
fantja Audiophile Posts: 15524 Location: Alabama Joined: September 11, 2010	Start w/ all cable/power cord connections.

RE: Rotel RB-1092 hum, posted on April 14, 2015 at 20:26:49

pictureguy
Audiophile

Posts: 22597
Location: SoCal
Joined: October 19, 2008

If nothing has been moved / altered MAYBE you are picking up some interference from an external source?
Try shutting off EVERYTHING you can. Dimmers? Fluorescent lights? Fish Tank pumps? Bed Vibrator?
If you have a small dish system, disconnect THAT and see if the problem goes away.

I'd hate to think one of your ICE amps had a problem. They are usually quite problem free. And have an on-board SMPS which operates at a fairly high frequency.

Problem with BOTH channels? Are you in an apartment with neighbors? Ask if anyone ADDED anything about the time you started having problems. New Fridge? Diathermy Machine?

Does the problem ease up or go AWAY very late at nite?

Fantja's suggestion is the good way to start. I'd add to DISCONNECT the input from the PRE. That's gonna isolate to the amp or 'over the air' RF / or thru the power cord.

Can you borrow a power conditioner?

without MORE information, virtually EVERYTHING is on the table.

Too much is never enough

Started? It did not at one point? What changed in your setup?, posted on April 15, 2015 at 08:53:49
Opus 33 1/3 Audiophile Posts: 4184 Location: D.C. Area Joined: February 19, 2014	New component? Something moved or repositioned? Different outlets used? Opus 33 1/3

RE: Rotel RB-1092 hum, posted on April 15, 2015 at 16:14:04
airtime Audiophile Posts: 11287 Location: Arizona Joined: February 4, 2003	Start disconnecting --one at a time with the amp OFF- sources then preamp. Is it both channels or one? Anything change lately? charles

RE: Rotel RB-1092 hum, posted on April 16, 2015 at 06:57:28
miner42 Audiophile Posts: 473 Location: Texas Joined: April 28, 2007	The is a Rotel RLC-900 used (conditioner)plus a shunyata power strip. I feel that possibly one of the ICs may have a shorted ground. Hopefully this can be tracked down by connecting one unit at a time until the hum returns.

RE: Rotel RB-1092 hum, posted on April 16, 2015 at 16:06:17
fantja Audiophile Posts: 15524 Location: Alabama Joined: September 11, 2010	Have you found the culprit?

RE: Rotel RB-1092 hum, posted on April 17, 2015 at 07:10:03

jea48
Audiophile

Posts: 6770
Joined: January 5, 2005

Do you have a CATV system connected to the H/T unit? If so disconnect the RG6 CATV provider's incoming coax cable from the cable receiver box and then check for the loud hum. If the hum is gone your problem is the earth ground for the CATV incoming RG6 coax cable is bad. There is a difference of potential, voltage, between the main electrical service grounding electrode system and the cable providers incoming RG6 coax shield ground that is causing a ground loop hum.

Post back your results after disconnecting the incoming CATV RG coax cable from the CATV cable box if that stops the hum. I will guide you through the fix.

RE: Rotel RB-1092 hum, posted on April 26, 2015 at 12:41:42
miner42 Audiophile Posts: 473 Location: Texas Joined: April 28, 2007	Not yet - it is at my B-I-L. I will see him this weekend and try to track down the issue and report back

RE: Rotel RB-1092 hum, posted on April 26, 2015 at 15:14:47
fantja Audiophile Posts: 15524 Location: Alabama Joined: September 11, 2010	Looking forward to your report.

RE: Rotel RB-1092 hum, posted on May 4, 2015 at 14:10:51
miner42 Audiophile Posts: 473 Location: Texas Joined: April 28, 2007	OK, I was finally able to make the trip to my B-I-L and helped him reconect his audio system. I think I found the issue - one IC did not fit snugly and would work loose on it's own. We tightened the outer bands and now all is AOK. I initally told him it sounded like when you have your amp powered on and remove and IC without powering down.

RE: Rotel RB-1092 hum, posted on May 4, 2015 at 14:47:35
fantja Audiophile Posts: 15524 Location: Alabama Joined: September 11, 2010	Good to read it was a simple fix- miner. Happy Listening!

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Rotel RB-1092 hum

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