1095 VERY strange Buzzzz

[Locutus2k]

Hi! I need help: i have a 1095 hooked to a 1098. The unit with the ground pin attached has a small but audible buzz. If i disconnect the ground everything is dead silent. Ok, here's the strange thing.
If i disconnect the 1098 from the 1095 the buzz goes away. So i've tried a million and one combinations, then i've discovered that if i attach a *simple* RCA signal cable to the 1095, but i don't connect the RCA plugs to anything, the buzz comes out!!!!!!
How's that possible?? The RCA cable catch the buzz from air (ironic)??
Can the balanced inputs give some help? If yes, where can i find a RCA/balanced adapter?
Thanks for any help. .... this thing is driving me mad :M

[jlee]

The RCA cable is grounded and you're getting an indirect ground loop from another component. I once had a similar problem.

If you're 1095 is connected to the 1098... anything connected directly or indirectly to the 1098 (with interconnects) with a ground pin could cause this problem.

[Kevin D]

, but i don't connect the RCA plugs to anything, the buzz comes out!!!!!!Thanks for any help. .... this thing is driving me mad :M

I think you're experiencing two different buzz's that sound the same. The amplifier is a circuit looking for a completion. Hooking the cable up will introduce enough resistance for the buzz to go through but there's nothing on the other end to complete the circuit. No, balanced cables won't help and there is all ready a converter inside the unit (those aren't true balanced connectors, they get converted inside the amp).

The 1098 picks up noise pretty easy and the ground path goes through the 1098, rca cable, through the amp, then out the ground pin. Does the amp hum when only the 1098 and 1095 are hooked together and plugged in (nothing else plugged in or connected?) If so, look for a faulty 1098,1095, or rca cables (which might help explain the 'thin-air' mystery).

If not, slowly add components back in until it hums. Most likely a DSS dish cable or your TV cable. It's real easy for a bad cable ground to go through a TV, through the video inputs, to the 1098, to the 1095, and out to ground..

Good luck,

Kevin D.

[hamiltong]

My question is why doesn't Rotel address this ground loop problem to help eleviate these very issues - a design that overcomes deficiencies in common household grounds enviromnents. I still am trying resolve this issue (months after upgrading to 1095 & 1068). I know that Rotel is not the only manufacturer plague by this, but it's a small minority of HIFI manufacturers that seemed to be more proned to this problem (or more sensitive to ground problems) then others.

FYI - My ground loop was caused by my DSS system - DC grounding block not being tied to the household ground. The different ground path from the DSS system passed the problem along through the Svideo cables through my TV back to my 1068 via component video cable and into the 1095 via the audio patch cables.

Even when solving my ground problem - I still have a very minor hum/buzz coming through my speakers (only audible when listening directly next to tweeter).

Bottom line is the Rotel 1095 is not very forgiving when it comes to electrical problems. Over the years I've had several different amps and never had these types of problems (all with same source components) - but on flip side this is the best sounding amp I've owned to date.

Hopefully, Locutus2k, you can quickly solve this problem and start enjoying your system. -gh :tv:

[ht_addict]

My question is why doesn't Rotel address this ground loop problem to help eleviate these very issues - a design that overcomes deficiencies in common household grounds enviromnents. I still am trying resolve this issue (months after upgrading to 1095 & 1068). I know that Rotel is not the only manufacturer plague by this, but it's a small minority of HIFI manufacturers that seemed to be more proned to this problem (or more sensitive to ground problems) then others.

FYI - My ground loop was caused by my DSS system - DC grounding block not being tied to the household ground. The different ground path from the DSS system passed the problem along through the Svideo cables through my TV back to my 1068 via component video cable and into the 1095 via the audio patch cables.

Even when solving my ground problem - I still have a very minor hum/buzz coming through my speakers (only audible when listening directly next to tweeter).

Bottom line is the Rotel 1095 is not very forgiving when it comes to electrical problems. Over the years I've had several different amps and never had these types of problems (all with same source components) - but on flip side this is the best sounding amp I've owned to date.

Hopefully, Locutus2k, you can quickly solve this problem and start enjoying your system. -gh :tv:

Your buzz is not a ground issue but the toroidal transformer itself. I had the same problem when I had the 1095 and still get it now with my NAD S250. So I wouldn't worry.

As far as Locutus2k problem try this:

1. Disconnect your TV coax from the TV
2. If you use Coax between your DVD player and receiver disconnect
3. Disconnect the sub coax cable from your receiver.

Now hooked your receiver interconnects to the amp. Do you get the noise. No?

1. Start connecting back the stuff you disconnected one at a time till you get the noise

I'm pretty sure you can hook up your TV cable but once you hook back your coax cables for DVD to receiver or sub you'll get the noise. Switch to an optical cable between your DVD/receiver. For the sub your stuck. If you still get the noise after switching to optical, yet hooking up the sub try this.

1. If you have a power conditioner or power bar run your tv cable to the conditioner tv coax input on it then run from the output to the tv. This should ground your system..

This worked for me when I had my 1095. With my NAD the hum returned when I installed my new HD Digital box. It was due to the coax cable between the receiver and HD Box. Switched it for an optical and the problem went away.

ht_addict

[EAmin]

hearing a buzz too

but they are coming from the speakers, not my 1095 or 1098. I don't know if we are talking about the same thing. From what I gathered in other posts, it sounds like my issue could be grounding. Does this sound right?

[jlee]

With the 1095, you will hear a FAINT buzz (from the transformer) THROUGH the speakers (and from the amp itself if you put your ear close enough)... with a ground loop, this Buzz becomes ANNOYING even from far away. So basically, the ground loop will make the buzz a lot louder.

[Locutus2k]

The RCA cable is grounded and you're getting an indirect ground loop from another component. I once had a similar problem.

If you're 1095 is connected to the 1098... anything connected directly or indirectly to the 1098 (with interconnects) with a ground pin could cause this problem.

I'm very sorry for my bad english (i write from Italy), maybe i wasn't enough clear in my first post.
After several combinations, i've tried to connect an RCA cable to the 1095 and i've checked for the hum powering on the unit *before* i connect the other end to the 1098 or anything else.
Well, the small hum from the woofer (and tweeter too) was here, and the other end of the RCA cable was NOT connected to anything. I've also tried a high-end (sort of) RCA Monster cable, but nothing changed.
Please note that if i disconnect the RCA cable (connected to nothing) the hum goes away!
I have to admit that the hum is not so strong and you can hear it only with your ear near next to the woofer/tweeter, but it disappear completely if i disconnect the ground pin with a cheated plug adapter.
I'm pretty shure that the hum appear ONLY when i connect an RCA cable to the 1095 inputs, no matter waht's on the other side, even if there's nothing to the other side!! 8O
I think that in the end i'll use the cheater plug ....
Thanks again for your help and sorry for my bad english,

Luigi

[EAmin]

Thanks jlee! The buzz is definitely not too bad, and is something I can learn to live with owning this amp. I'm hoping the RB 1090 that I ordered will be as quite or will make less noise. This is all so new to me. Thanks again!

[aarsoe]

Its funny that this keeps comming up on Rotels high end products. The real question is why Rotel dont spend the engineering time getting this fixed, once and for all. I have had my 1095 in several times based on this, but there are alwayes problems with noise.

To all the clever guys, could this have something to do with the way you select between balanced and un-balanced inputs. I mean your supposed to use the special rca plugs that pushes a switch inside the rca jack - so does this not mean that there is a circuit running inside the jack with some kind of current? Come to think of it, that could very well be the reason why the amp is picking up noise, when a cable is inserted..
Any viewpoints on this?

[Kevin97225]

RB-1090 does it too.

I have the RB-1090 and it sends a slight buzz to the speakers too, you can hear it when you get near the speakers.

I've talked to Rotel about the problem........the tech people made it sound as if I'm the only one having this problem.

I talked to my dealer where I bought it and they checked out their RB-1090 demo unit and they had the same problem with it. Thing is, if I have all Rotel equipment connected......... it's pretty silent. If any brand.....no matter what other brand.....it connected to the Rotel.... the slight hum is back. The dealer had the same findings as I.

I love the RB-1090 Amp. I listened to alot of amps costing alot more and still the RB-1090 did everything all-around just right, very smooth, wonderful sound, huge soundstage, very deep tight bass, very nice detailed highs and very smooth too. I love it. I think it's the best Amp out, very warm tube like. No reason to pay more of an Amp because the Rotel RB-1090 just does every thing right in an all-around right way. You will LOVE IT.

Kevin.

[GosonFletchy]

I am not sure that there is any magic company out there that can make a product gauranteed not to hum or buzz in any environment. These problems are definately annoying but if it were a design flaw don't you think that every single person that every bought one of these would complain about it and then eventually no one would own one? Try grounding the chassis of the amp with the processor. A simple ground wire from a screw in the back panel of the processor to a screw in the back panel of the amp. This may help. Try doing this with all of your components. It could be that you have dirty power and your components are picking up the noise. Maybe a mains filter is a good idea as well. Just a few things to think about.

G.

:grab:

[Locutus2k]

I am not sure that there is any magic company out there that can make a product gauranteed not to hum or buzz in any environment. These problems are definately annoying but if it were a design flaw don't you think that every single person that every bought one of these would complain about it and then eventually no one would own one? Try grounding the chassis of the amp with the processor. A simple ground wire from a screw in the back panel of the processor to a screw in the back panel of the amp. This may help. Try doing this with all of your components. It could be that you have dirty power and your components are picking up the noise. Maybe a mains filter is a good idea as well. Just a few things to think about.

G.

:grab:

Everything you say makes sense, but if you consider that the buzz is here even with a simple RCA plug attached to the amplifier with nothing else on the other side, i think that the only way to eliminate the slight buzz is cutting off the ground pin from the power chord (or use a cheated a/c plug adapter).
Maybe the many people that don't hear the buzz don't even have the final grounded: you may wonder how many houses don't have a correct ground wiring.
All the best,

Locutus2k

[ht_addict]

Everything you say makes sense, but if you consider that the buzz is here even with a simple RCA plug attached to the amplifier with nothing else on the other side, i think that the only way to eliminate the slight buzz is cutting off the ground pin from the power chord (or use a cheated a/c plug adapter).
Maybe the many people that don't hear the buzz don't even have the final grounded: you may wonder how many houses don't have a correct ground wiring.
All the best,

Locutus2k

Did you try any of the suggestions I gave in my reply? Try them and see what happens. As far as putting a RCA cable into amplifier and leaving the other end unattached and getting the buzz, is due to the fact that your showing the amp a load by making the connection. Because the open end isn't attached and grounded its picking up stray noise. The amplifier is just magnifying that noise.. Try my suggestions before you cut the ground.

ht_addict

[THX1139]

I was considering upgrading to some Rotel gear. If this is the kind of qaulity control I can expect from them I will definitly be looking somewhere else.

[Kevin D]

I was considering upgrading to some Rotel gear. If this is the kind of qaulity control I can expect from them I will definitly be looking somewhere else.

Trolling, trolling, trolling...

[EAmin]

According to my dealer who I trust and is very knowledgeable in the field, this is a common problem mainly from video sources sharing the same circuit as the audio equipment. Some have mentioned this early in the post. For me, I'm thinking it is my satellite installation that I need to investigate. And it may not be sat unit that is used with my HT, it could be other rooms impacting this as cable coming from the dish may not be properly grounded. Or it could be a bad cable for one of the components. He said (as others have stated), you have to investigate the problem component by component, until you find the source. Apparently, it doesn't matter if Rotel or if it's a $50K Krell system, you can still run into these problems. It's a pain as the last thing I want to do is to solve a mystery --- I just want to enjoy my system.

Some of us may be lucky enough where we experience no problems, others need to do some tweaking. It's just something we have to deal with I guess.

I'll let you know how it goes with my setup.

[Azeke]

Trolling, trolling, trolling...

Now, now Kevin D 8) . Let's treat our guest nicely.

Azeke

[GosonFletchy]

I was considering upgrading to some Rotel gear. If this is the kind of qaulity control I can expect from them I will definitly be looking somewhere else.

You should look somewhere else.

G.

:grab:

[Kevin97225]

It's not just Rotel THX1139!

I was considering upgrading to some Rotel gear. If this is the kind of qaulity control I can expect from them I will definitly be looking somewhere else.

Well, it's not just Rotel. Some problems are due to some's home ground wire not done right, others are from cable or satellite that can easily be fixed with an adapter, others are caused by the video from DVD players.

I have 3 different Amps of different makes and they ALL have this problem and one of the Amps cost 3.2x the cost of the Rotel RB-1090 so you see, it all depends on what is causing the problem. It's not the amps fault so even with your search for another brand..... you still aren't guaranteed that you won't come across this problem! But first off, remember to not judge something that you have never tried or you could be doing yourself a great injustice!!! You will just love the quality and sound of Rotel!

[Micke.H]

the osd cable ...thath was my problem anyway..

[Mitchell]

I have a 1080. When I set it up initially it worked perfectly. A few days later I hooked the cable box up through the Rotel Preamp so I could listen to the cable music stations through the stereo. Immediately I had a hum. The hum was evident even when I tried to use the CD or tuner instead of the Cable input.
I ran the cable box AC and the cable input through the monster power strip and it immediately went away never to return (so far).
When I consulted the dealer he said that it was very common for cable connections to introduce ground loop problems.
I know this is not specifically your problem but it might help lead you to a solution.
Hope its helpful.

[ht_addict]

I have a 1080. When I set it up initially it worked perfectly. A few days later I hooked the cable box up through the Rotel Preamp so I could listen to the cable music stations through the stereo. Immediately I had a hum. The hum was evident even when I tried to use the CD or tuner instead of the Cable input.
I ran the cable box AC and the cable input through the monster power strip and it immediately went away never to return (so far).
When I consulted the dealer he said that it was very common for cable connections to introduce ground loop problems.
I know this is not specifically your problem but it might help lead you to a solution.
Hope its helpful.

Do you have the box connected to your receiver via coax? Switch to optical and you'll solve the problem without going throught the power strip.

ht_addict

[ekkoville]

HT addict, good idea. Never thought of optical as a solution. If there is component cables from the pre/pro to the box or TV the humm will travel through those. It did for me, anyway. Any cable, aside from optical, connected to the TV or cable box sent the humm to the pre/pro. I have the the M..... power strip to run cable through it, but have not tried it yet. Still using the cheater plug, not for long though.

Erik