RB1080 new addition

[Al K]

Recently purchased an RB1080 for my front speakers. Using an RSX1055 for the center and rear channels. Initially, the RB1080 caused a loud hum through my speakers. The dealer suggested using a 3 to 2 prong adapter with the AC cord. This eliminated the hum totally. Upgrading to the RB1080 was well worth it.

[Aussie Geoff]

Al K,

Glad you like the RB-1080 it’s a great amp and should give you many years of listening pleasure.

Re the Hum - almost certainly you have a ground loop. Most likely it comes from your Cable or Satellite or TV line into the Receiver. When you feel like it, remove the 3 to 2 pin plug and try disconnecting all of the inputs from your Receiver. Add them back one at a time and you'll find the source. There are some good posts on this forum as to how to get rid of the hum. Summarised:

• If it's your cable get the cable company back to fix the grounding or put in a ground isolator
• If it's your aerial - get an line isolator
• If it's your satellite - get a ground loop breaker.

That hum is almost certainly a small earth leak looking to go to ground and entering your Receiver and then travelling down the RCA leads into the RB-1080 and down its earth.... Worth getting rid of properly if you can.... Otherwise it will reappear when you add the next 3 pin HT appliance (say that great sub you’ve been lusting after – which will play the hum realllllllly well!)

Geoff Costello

[Al K]

Thankyou for the info. I'm sure it will come in handy!

[Azeke]

Al K,

Congrats on your new purchase, I'm sure it's a real treat.

Geoff, provided a very accurate trouble shooting list, which may isolate your issue.

FYI, there is also a newer version of the RB-1080 that has 4 binding post.

Enjoy,

Azeke

[Al K]

Azeke,

Thanks for the congrats. I heard about the newer version of the RB1080 before. My dealer was not aware. Could you clarify the difference between the newer and the older. :?

[Azeke]

Al K,

The newer version has four speaker posts in the rear for bi-amping I believe, and I also believe some internal parts were revised. I talked to my dealer when I first upgraded my amp and informed him that I would only purchase the newer version. He thought it was the overseas version, but I was quick to correct him .

Perhaps some other forum members can elaborate on the internal revisions.

Regards,

Azeke

[Al K]

Azeke,

Thanks! Due to curiosity, I'm going to check further into the differences on the newer version RB1080. If I find anything new and of interest, I'll pass it on.

[Al K]

Geoff,

Your accuracy is much appreciated! The SOURCE of my hum was my cable. Took off the cheater plug, disconnected the cable and no more hum. Oh, the RB1080 sounds terrific!

AL

[Azeke]

Al,

Happy to hear the news about your RB-1080.

The funny thing is now that I have the RB-1080 , my friends prefer to listen to 7 channel stereo mode via the CD player, what do they know :LOL: .

Did you check to see which version you have?

Regards,

Azeke

[Al K]

Azeke,

It appears I don't have the newer version,since I only have one set of speaker terminal posts. However, I read that the only difference in appearence was clear plastic over the terminal posts which my 1080 does have. (Maybe I do have the newer version). Don't remember where I read this. I e-mailed Rotel about 3 days ago, no answer so far. My dealer is also checking into it for me! In either case, if all is working well (and it is) then I'm happy This amp simply sounds to good

AL

[Al K]

To all curious RB1080 0wners,

I called Rotel tech support personally to clarify the differences between the newer version of the RB1080 and the older version. The newer version simply has two sets of binding posts for bi-wiring added. AS per Rotel, no internal changes were made. The guts, specs and performance on the newer and the older are identical.
P.S. Almost gave my dealer :twisted: . But after all is said and done, I'M
Al