RB-1080 Problems

[gjmen]

I recently purched a RB-1080 to power my 604 S3'S. I was previously using a RMB -1075 for 5.1 but thought the 604's were a little under powered. So I added the 1080 for the front 2 speakers, and that will free up 2 channels on my 1075 for a future 2nd zone. The problem is a humming sound coming thru the speakers hooked up to the 1080. The amp is plugged into the same power conditioner as the 1075, so I dont think it is a power isue. I also am using the same rca's as before. I have the ampliers installed about 4" apart and have switched the speaker wires and rca's back and fourth. I always seem to get the same humming when using the 1080. Any Idea's? Do I have a bad amplifier? Thanks,

gjmen

[htsteve]

I recently purched a RB-1080 to power my 604 S3'S. I was previously using a RMB -1075 for 5.1 but thought the 604's were a little under powered. So I added the 1080 for the front 2 speakers, and that will free up 2 channels on my 1075 for a future 2nd zone. The problem is a humming sound coming thru the speakers hooked up to the 1080. The amp is plugged into the same power conditioner as the 1075, so I dont think it is a power isue. I also am using the same rca's as before. I have the ampliers installed about 4" apart and have switched the speaker wires and rca's back and fourth. I always seem to get the same humming when using the 1080. Any Idea's? Do I have a bad amplifier? Thanks,

gjmen

gjmen,

It could be the amp. But it also could be some other issue in the system.
On a scale of 1 to 10 (1 being very quiet, 10 being loud and can't listen), what is the level of your noise?

Most systems have some level of system noise or hum. The trick is getting good enought equipment and conditioners to try to reduce it. Also, a dedicated circuit for your AV equipment is a good idea. I realize it costs money, but your setup would be all by itself. Also, make sure your equipment is plugged into the same circuit, even if shared with something else.

Try this: plug the 1080 directly into a wall outlet instead of the conditioner. See if that eliminates it, or reduces it to a tolerable level. Something plugged into the conditioner maybe an issue.


Another possibility. I had a new 1080 a few years back. I recall back then that there were some issues with one of the channels going out, I believe it was the left channel. Mine did have the left channel go out, twice I think. This issue I had seems a bit different. The amp sounded very good, but suddenly a channel would go out. I hope this is not your issue.


Hope this helps.

[gjmen]

Re 1080

thanks for the help Steve. I did try your suggestion of plugging the 1080 into the wall outlet and not the reciever, and had no luck. I still had the humming sound. As far as some systems having this humming sound, that just doesnt seem right. In all of the years of playing around with sound and sound equipment, I never had this issue, and my equipment has been much cheaper in the past. I do wonder about the 1080's grounded plug. This is my only peice of equipment with a 3 pronged plug. I not sure why the 1080 has the 3 pronged plug and the 1075 doesnt. As far as the humming being tolerable, I only notice it when putting my ear close to the speaker. Thanks, gjmen

[Kevin D]

Sounds like you have a ground loop problem that has become noticeable due to the 3-pin plug on the 1080.

You can try a 2-3 prong adapter, but might want to go through and try to track down what it is. Check anything plugged into you system that's not plugged into the same outlet. IE, subwoofer, TV, phone line, cable/dss line, etc..

In the end though, any hum you have to put you ear to the speaker to hear is nothing to really be concerned about.

Kevin D.

[gjmen]

1080 humming fixed

I disconnected the CATV feed and the humming went away. I reconnected the CATV feed and grounded the splitter, all is well. Thank you everyone for your help. :T

gjmen

[htsteve]

I disconnected the CATV feed and the humming went away. I reconnected the CATV feed and grounded the splitter, all is well. Thank you everyone for your help. :T

gjmen

Excellent.

[Kevin D]

Good deal!

Kevin D.

[joetama]

I disconnected the CATV feed and the humming went away. I reconnected the CATV feed and grounded the splitter, all is well. Thank you everyone for your help. :T

gjmen

I had a similar problem, but I broke out the O-Scope to try to find it and the CATV feed was my problem as well. Had around 1volt p/p noise on it, which was ugly and rather scary. After grounding the plug, the splitter, and the cable box with external ground wires ran to a separate solid ground the noise was cured.

Glad you found it and worked it out, humms are super annoying.