Need help with ongoing 1095 amp buzzing with 1066 preamp

[denass]

I need some help please.I have taken the 1095 5 channel power amp in several months to get rid of the dreaded buzz--hiss that has plaqued this model.I live in adelaide australia.It was in for six weeks at audio video here to be fixed.They were the Rotel agents.Well no luck.The agents here had contacted Interdyne the australian agent and they said they had not heard of a fix.Then they said they had after 5 weeks of no amp.It came back to me basically the same.I am a Hometheatre installer here in adelaide and have tried everything I can think of to eliminating the buzzing.I have used cheater plugs with no earth,tried heaps different interconnects which made slight difference.In frustration I sold my $4000 yamaha amp that I was using as a preamp and bought a 1066 thinking this might help both being rotel.But no such luck it became worse.I have dropped both the 1066 and the 1095 into TVM a agent for Rotel but they havent done much with rotel.I need some hard facts from rotel to TVM here in adelaide urgently to get this thing fixed.Interdyne has not been useful in coming up with a solution.I would love it fixed.Has the newer models of the 1095 this same problem. Is there away to get the needed info directly from rotel to TVM cause going thru Interdyne is a complete waste of time.I rang Interdyne and spoke to a techy but he had no idea.Would really appreciate any help.
thanks Dennis

[JDH]

Have you tried running an earth direct beween the RSP-1066 and the RMB-1095. I assume from what you have said you have tried disconnecting everything and slowly connected components until you here the buzz or are you getting the buzz sound with only the RSP-1066 and RMB-1095 connected? I own the RSP-1066 and RB-1080 + RMB-1075, for a short period I was using a Yamaha RX-V3000 as a pre-amp and I was having a similar problem to what you describe with the RB-1080, however in my case the upgrade to the RSP-1066 solved that problem.

[denass]

thanks JDH
Yes did try earthing both units together.The 1095 power amp is renown for doing this.With only the speakers connected there is silence.As soon as you put even one interconnect on the buzzing starts.Have heard there is a fix but it is in the amp but has to be done by a rotel service agent.My 1st 1095 was damaged in the box--the transformer was loose.I really need a reponse from rotel.
thanks again
dennis

[Dan Nelson]

I had a similar problem (not with Rotel brand). Do you have an antenna cable connected to one of your components? In my case it was the cable TV/FM connected to my tuner that caused the buzz. (Don't know if you have cable tv there?). I've putted a wire between the mass of the cable tv connection box and the earth of my electrical installation and the problem was fixed...
Good luck !

[denass]

thanks Dan
with nothing connected silence but as soon as you connect the preamp to the power amp--buzzing.Nothing even connected to the pre-amp,no dvd or anything.I think it is a earth loop and have heard that they change the input resistors on the power amp.I am a home theatre installer so have considerable knowledge in the field of connecting equipment but this is definitely the 1095 power amp problem that has occured.It has been a known problem with this amp by rotel.I would like to know if the later versions had fixed the problem then i could ask for a new one.I am fed up with this amp and wish rotel would come out and say how to fix it or get a new one.
Thanks agian
dennis

[hidefdvd]

Dennis,

Ask your Rotel dealer about replacing the input resistors on the 5 channels. I had a buzzing problem with my 1095 and that was the problem. Otherwise try some of these solutions:

1. Unplug everything except for speakers.
2. Use optical hookup over coax where possible. That should leave you with just the sub hooked via optical.
3. If you have cable tv or sat, run the tv coax to a surge protector then into the tv.
4. Now start hooking things back up and see if the hum comes back. Hook the sub coax up last

Unfortunately your 1066 doesn't have an FM cable hookup. When I had my 1095 is was mated with a pre/pro that had this type of hookup, so I ran a piece of tv cable from it to the surge protector and it removed the hum instantly. On another note the problem isn't only Rotels problem. I now have a NAD S250, that was dead silent until I hooked my Motorola 6412 to my 56TXi via coax because the hum returned. Switching out the coax for optical got rid off it.

[denass]

thanks Hidefdvd
have tried all that
the preamp nothing I mean no coax or optical connections whatso ever,just the preamp and power cord for the preamp.The power amp with speakers connected.I only have to connect a single interconnect from the preamp to the power amp and the buzz starts.I can assure you I have tried every conceavable way to try and eliminate it.It has happened in 2 houses so far and checked house mains wiring and earth ok.I dont want to do anything myself to the inside of the amp to void warranty.This buzz is common with models out awhile back.Hoping someone can shed some light on the internal fix so that the place that has it at present can short cut the wait or give me a new amp.
I must say again it is a common fault with the 1095 power amp.From what I have previously heard it was a design flaw between balanced and unbalanced inputs as its smaller brother didnt suffer from the same problem.
thanks
Dennis