1098 Hiss

[egaither]

The noise floor of my 1098 seems much higher than what I had on my Yamaha RX-v1400. How do I verify something isn't wrong, cause I'm thinking there is. I'm using a Monster line conditioner which improves it some, but it is still pretty bad.

I love this pre-amp other than this issue, so I have been hesitant to bring it in to the dealer. I finally received my 1090, same level of hiss as the 1095. I unplugged the interconnects from the amps and dead quiet.

HELP!

[Andrew Pratt]

It sounds like the issue isn't with the gear but your electrical system. Is the HT gear on its own dedicated line or is it shared with something else? Do you have cable or satellite?

[DrBoom]

I don't think there is anything "wrong" with your unit, I've heard lots of people complain about a high noise floor on the 1098, including myself. :roll:
It has nothing to do with line filters, cable/satellite stuff, it's just a noisy DSP board.
There are however several different DSP boards out there in various 1098's, and some types are less noisy than others.
I don't know if the new ones have the better DSP's, or the older ones, or the ones in between.
Rotel is fully aware of this issue, and also that the hiss increases with volume from around volume setting 64 and up.
Noise is also my main issue with the 1098, I find this amount of noise not acceptable for a product of this price as there are dozens of receivers out there that are absolutely dead quiet at 1/3 the cost so it can't be that hard or expensive to make.

Try the following, connect your CD player to an analog input and select Bypass mode, or connect it to the multichannel inputs.
Those are the only inputs that DON'T hiss, everything else does.
As soon as the DSP board is involved, you get hiss.
And as long as you stay purely analog, it's fine.
Too bad a pre/pro isn't meant to be used in pure analog mode :roll:

[egaither]

The system is on a dedicated line. I have tried disconnecting all interconnects video/audio from cable, as well as all other unnecessary components from the mix. Even with just the amps, the processor and dvd player, I have hiss. The only way I have been able to be rid of the hiss is to disconnects the inputs into the amps.

I typically play CDs using bypass analog inputs and I have the same issue. The hiss is the same no matter which input I choose.

[jlee]

DrBoom, Does this hiss exist when using the coaxial or optical inputs?

I have not found it a problem with 2 channel bypass with CD like you said.

[DrBoom]

The only way you DON'T get hiss is using the multichannel analog inputs OR the normal analog inputs in BYPASS mode, not STEREO mode or anything else.
Everything that uses either the DSP or A/D converters is affected by hiss at higher volumes. (starting from around 64)
But I think the listening distance is also a major factor in this, listening at 3m with volume at 64 is much more annoying than listening at 6m with volume at 76 for example.
And because I'm still in a small room, hiss is a major factor for me.
Reference level is around 68 - 70, and I normally play at 60 - 64 maximum.
At 60 the hiss is relatively quiet, but there's still a "feeling" of hiss, it's not dead quiet.
At 64 the hiss becomes way more noticeable, and anything over 64 is downright annoying and distracting.

[jlee]

I'm usually around 65-70 for Satelitte, 70-75 for Music, and 75-80 for movies. I haven't yet noticed this, but I will test it tonight and let you know. I am 8ft from all speakers so I should be in the "more annoying" range .

I did notice a RELATIVELY high level of hiss on my old RSP-1066 compared to OTHER hifi gear I've had in the past (eg. NAD 7400 receiver, which was SUPER SUPER quiet even at MAX VOLUME you'd have to put your ear right to the speaker to hear anything). It's one of the major complaints I have with Rotel. Maybe I just got used to it and don't notice it now... well I will do the testing tonight and write back.

Cheers.

J.

[THX1139]

Wow, I am glad I read this thread. I was considering a major upgrade to some Rotel components, but if this is the kind of qaulity control I can expect from Rotel I will definitly look for a different brand. I will not pay good money for any HT equipment that has a "hiss" or any other background noise.

[PiDD]

Well not EVERYONE gets the hiss. Besides you will have to change your handle! :wink:

[Mark_C.]

My 1066-1075 combo makes no hiss at all, whether connected by analog or digital.

[Zzap]

I have so far never had a setup that did not hiss at a one volume setting or other with no audio playing.

Granted, there has never been room in my budget for something like a pure Mark Levinson or Meridian setup.

At that price I'd expect more but with my current setup (including RSP-1098 and RMB-1075) I'm only able to provoke a hiss at a very high volume setting - still with no audio playing (so high a setting in fact that I'd probably prefer being two blocks away if I played a CD).
I guess I'm blessed with relatively clean power.

I understand complaining about hiss if you hear it at a setting you normally use (without - or worse - with audio playing) but I'd ignore it at extreme levels.

If you're in the market for new HT gear, why not ask for a loaner.
The reason for hiss is often external to the unit (cable, etc).

[DSGCobra]

Wow, I am glad I read this thread. I was considering a major upgrade to some Rotel components, but if this is the kind of qaulity control I can expect from Rotel I will definitly look for a different brand. I will not pay good money for any HT equipment that has a "hiss" or any other background noise.

and you will be missing out.

[egaither]

My complaint really is if I wish to listen to my system at say 60-65 I should be able to. The problem really is quiet portions of a DVD/CD where you really hear the hiss. It is just distracting.

My point is that is wasn't there with my yamaha which is an inferior unit as far as sound quality goes, but there was probably only half of the hiss that I receive out of this unit—that is messed up IMHO.

[BlazeMaster]

egaither, I live in the same area as you as well, also in San Jose, CA. Which dealer did you get your Rotel gear from? When did you buy it? If not over a month, bring it back and take a different unit home and try it out, see if the problem still there.

[Aussie Geoff]

egaither,

If you can hear the hiss at normal volume levels while sitting down - there is somthing wrong - most probably either with your power supply OR the 1098 unit itself... (There have been a few faulty units)

The hiss 99% of us are talking about requires you to be 30cm (1 foot) or so away from the speakers to hear at normal listenning levels... (Not good I know but largely more of a "becuase you know it's there" issue rather thany anthing else...)

I had some minor hiss with my 1098 at 30Cm comencing at about 10 db belfow reference level which I reduced to inaudible using a power filter (I need to put by ear right on the tweeter now at the same volume)... I can still get hiss - but I need to set the unit at well above reference level (deafenning volumes) to hear it even 30 Cm away from the speaker - and certainly the level of hiss I get is no worse (probably less) than my previous Denon 3802 Reciever... To get a faint hiss I can hear sitting down I need to set the volume to above 90 which (for my speaker amps) is 16db above reference OR 120 dB plus (I suspect it would damage my hearing if I actually played anything at that volume!)

Geoff

[egaither]

BlazeMaster—Got it from Century Stereo. I called service but just want to exhaust all options before shipping it off to Rotel. CS is quoting a 5 week turn time including shipping to Rotel and back. I purchased it several months ago now. I had a substantial hum that I finally got rid of, and was pretty focused on that, along with other upgrades. I guess I could see if they are open to letting me bring another one home—haven't asked.

AussieGeoff—The hiss/noise can be heard loudly from 7-8 feet away with volume at 64 test tones are 75db with mains and center roughly 7-8 feet away. After rereading some of the previous posts I did find out that the multi-analog outs ARE significantly quieter. I am able to turn it all the way to 85 with little hiss and unless you are right up on the speakers, you cannot hear it—acceptable. When switching to digital that's where lots of hiss kicks in. I'm using a tributaries coax cable.

[Aussie Geoff]

Egaither,

That level of hiss is (for me) unacceptable (way way more than I get - sounds like it is occurring at a 20 dB lower volume that I get). I'd borrow a loan unit from the store - if it does it as well then it's probably noise on you power and a quality mains filter will help, if it doesn't then you probably have a faulty unit with noise on the DSP...

Geoff

[DrJRapp]

Egaither,

There is something else factoring in here that nobody has brought up. I noticed in you system profile that you use Klipsch Reference 7 series. These are the same as I have for my system.

I think you may have gone way way into overkill with your amps, but don't we all! This may be part of the problem.

Because of the extreme high efficiency of the Klipsch, noise generated by any audio equipment in the chain will sound more pronounced than it will to others who have lesser efficient speakers.

Back in my RSP 1066 days, I used to have a hiss in my center channel speaker, actually it was more of a high frequency buzz than a hiss. Sometimes it would be there, sometimes it would not. Drove me crazy. The real interesting thing, an what got me really searching was that the buzz was there with my equipment turned off!! Talk about spookey .

Well, I finally tracked the source of the noise to my ceiling fan. The fan was equipped with a solid state speed control device that must have been emitting some spurious RF. This RF signal was being picked up by my speaker cable and was being rectified somewhere in the RC7s crossover to produce noise. I not am saying this for you to go hunting for a similar situation (although perhaps you should) but to illustrate how sensitive the 7 series Klipsch really are. RF7s can be powered by a walkman! Imagine how miniscule the power was that the fan was able to induce, yet the RC7 produced audible noise. I solved the problem by replacing my Monster speaker cable with a high quality twisted pair speaker cable, by the way.

Perhaps your 1098/1095 would be dead quite when connected to a speaker with an efficiency rating of say...92dbw/m, like a B&W for example, where in may not be with the R7 series' 102. So, don't be surprised if you send the 1098 away and are told that it is within spec or that the problem cannot be duplicated by Rotels service centers.

You will probably be thinking once again...I didn't have the problem with my Yammi. There are a lot of reason's why this could be, all of which have to do with the 1098s abilities over the Yammi, not it's disabilities. However, it is late and I am tired, so those explanations will have to wait for another day.

[egaither]

DrJRapp—Wow that is pretty crazy with the ceiling fan. Just checked out your profile, you have a SVS PB2+ sub too. I just got mine last week. Just updated my profile. This thing is a beast. So far it is pretty impressive—sorry for the tangent.

I understand Klipsch speakers are pretty revealing. I'll accept a little noise, but I have had the main speakers from day one and they didn't hiss like this before. Also the fact that the noise/hiss level is reduced so greatly when using multi-analog inputs reinforces something's not quite right.

Mains and center are biwired w/ 12 gauge Monster Speaker wire. Transistion went like this:

1.) Yamaha RX-V1400 alone with RF7s (speakers are efficient and 110w/channel was adequate until I could afford to upgrade)—very little hiss
2.) Yamaha RX-V1400 w/ 2 channel Carver Amp (Got this for 2 channel listening)—very little hiss
3.) Yamaha RX-V1400 w/ 1095—don't recall any change in hiss
4.) 1098 w/ 1095—hiss
5.) 1098 w/ 1095 for surrounds and 1090 for mains—hiss

I spoke with service at CS and they requested I try removing the DVD coax cable to verify it is not the DVD player. And that is not the culprit—same level of noise/hiss with coax cable removed.

[Fox]

The hiss is simply there...

I have it also, but i've you don't believe a user,
check the test in Widescreen Review fom last year.

They found it a serious problem...

[egaither]

Fox—I'm not so sure about that. I assume the hiss/noise they are referring to in that article on the last page is related to the video shield problem—I already have had it installed.

I called Rotel directly and they suggested I upgrade from 2.12 -->2.13.

I can't see how this will fix anything, but I am willing to give it a shot. There isn't any mention of the hiss issue in Rotel's release notes.