pre-amp unacceptable noise level?


How much is an unacceptable level of noise/humming etc. from a pre-amp? I just bought a new tube pre-amp and when I replaced my old solid state one with it the noise level from the speakers practically tripled. There is an audible humming from the listening chair 10ft. away. I can't say I'm particularly happy with this considering the one I replaced did not do this.
fruff1976
Have you tried a cheater plug on your amp. Sounds like you might just have a ground loop.

If that doesn't work you might just need some low noise tubes.

What does the manufacturer say your problem might be? A very light hum or hiss heard from less than a foot from your speaker is not unusual IF you have very efficient speakers or an amp with a very high input sensitivity.
Humming sounds like a grounding problem. Is your TT grounded to the amp or pre-amp? You might try moving it around to different components.

Are all you components plugged into same outlet? If not, try that. If none of that works, then try the cheater plugs.

Dave
Sounds like you have a ground loop hum. This article should help you troubleshoot the problem.

Cheers,
John
Another cause of humming can be from locating a pre-amp too close to a power source, usually an amp on which some people like to stack stuff (ever noticed how many high end pre-amps come with seperate power supplies often connected to the pre-amp by a long cable), and proper cable dressing, that is, making sure all of your IC's are not near any power sources or power conditioners. I've had problems with both of those issues. Easy to cure. BTW this is generic advise - I've never owned a Rogue.
My Rowland 102 amp introduced a major hum into my setup. Turned out to be the cable TV. A Jensen Ground Loop Isolator fixed me right up.
I don't have t.v. hooked up into it. It's just a 2 channel rig with a cd player and I haven't hooked up my turntable yet.
Not sure how to bias tubes? This is my first tube pre-amp. Also, after hooking up my old solid state pre amp I noticed the system noise I'm talking about is present, but not as loud as with the rogue. Is it possible the noise is originating in my power amp and is being amplified to a greater degree with the rogue?
You do not need to bias the tubes with preamps.
The cheater plug would go on the power amp, if that is the problem.
Is it both channels or one? If one, you might have a bad cable.
If the hum is there with both preamps, then it is not the Rogue.
Tube preamps are usually not as quiet as solid state, but is would be the normal hiss sound that would be louder, not a hum.
There is an audible humming from the listening chair 10ft. away.
Just to be clear... is it hum or hiss? If it's hum, the advice above is all very good. If it's hiss, I suggest replacing the tubes with low noise variants. Tube hiss is common, but it can be fixed.
You should read this 10Audio review:

http://www.10audio.com/rogue_metis.htm

Particularly noteworthy:

"Downsides? A few. The Rogue is loud. There's much more spurious noise through my 89 db sensitive Soliloquy 6.2s than I'd like, and not just tube rush. I did have some issues with hum as well. Listen carefully and you can hear this from your chair at around ten feet."
I'd say hum and hiss + buzzing. It's just noise which can be heard in the room when the unit is turned on. About 20 seconds after you turn it on the buzzing/hissing/humming starts.
UPDATE: when I switch out to my old preamp the same type of noise is still there, just much quieter. You can hear it maybe up to 1ft. away from the speaker. It seems as if this amp is just accentuating the noise to an obnoxious degree.
Dumb question- Is the noise only present when you rotate the volume control to its maximum position? Is it quiet when the volume control is in a position when the music is at a 'normal level' or even a bit loud?

If the answer to these questions you are just talking about your units noise floor or the noise from the (in your case) connected CDP. The fact that you do not hear anything for 20 seconds indicates that the 'hum' comes from your pre-amp (or source) which is muted on initial turn on to avoid transients while your pre-amp is stabilizing.

Try disconnecting the CDP and see if the noise level changes. If not then its the pre-amp. If you hear the hum/buzz etc at normal volume levels at 10 feet you've got a bummer and should contact Rogue for repair or replacement.
The noise is the same level whether the volume is up or down. It's independent of the volume level. The problem is during softer passages or listening at lower volumes the noises/buzz/humm/hiss whatever it is can be heard over the music. It can be heard even when the cdp is turned off and no music is playing.
The dealer was very cooperative along with Rogue and a new one is being sent. Rogue customer service along with the dealer has been outstanding so far.