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I suspect that you have a grounding problem.
If that is the case, getting a different phono preamp will not help.
There is nothing wrong with needing to turn it up to 12 o'clock, but there should not be any significant hum.
Do you have a ground wire connected from the turntable to the metal chassis of the amplifier? You should have one. Just loosen one of the cover plate screws on the amplifier chassis and attach the ground wire from the turntable to it.
I suppose it is possible that the phono stage of your Rogue amp is defective.
I would call tech support at Rogue Audio and work through it with them on the phone.
Commsysman, Thanks for the advice, but the ground wire is in place on both the amp and TT. I emailed Rogue and they seemed to think the phono stage has a relatively high noise floor that becomes more audible when the volume is cranked up. They thought it might be a gain issue with the cartridge. It is interesting that Rogue is updating the Cronus Magnum to the Cronus Magnum II and one of the upgrades is a better phono stage. If I knew it was coming I would have waited 2 months.
Hi Pete
You might also want to talk to Roy about the match up. He might know the trick for the gain you need.
To be honest the first thing that popped into my head was not the magic 3 but the amp/speaker/room combo. Do you have a dampened room or lower efficiency speaker?
Don't mean to butt in but, you should have a fair amount of gain there, or maybe Roy can speak to why.
good luck
michael green
MGA/RoomTune
http://tuneland.techno-zone.net/
There are several things that could cause that problem. I would start with grounding because that's free and a common problem with turntable-amp marriages. Removing a ground wire, while seemingly counter intuative, will sometimes correct the problem because the system is grounded somewhere else already.
Next I would suspect a cartridge and tonearm issue. Not all cartridges play well with various tonearms. However, if the combination worked for the dealer when it was installed then I wouldn't consider that to be an issue. If someone simply replaced the cartridge with a different one and suddenly there is a problem, then it's very likely they don't mate well and you'll have to spring for another cartridge...after consulting with the dealer about which cartridges mate well with your particular arm. Maybe give Needle Doctor a call?
RCA cables that are well shielded might fix the problem, but that tends to be less of a "hum" issue and more of a "hiss" issue.
Using a different power outlet to power the turntable and the amp and keeping the cables well away from each other can sometimes help with noise, but that's more of a higher frequency noise as opposed to a 60hz type of hum noise.
In any event, I wouldn't start spending money to troubleshoot it without knowing where my problem is. A new preamp does nothing to fix a cartridge/tonearm mismatch and nothing to fix a ground problem that couldn't be fixed without spending money on a new preamp.
If possible, I would tote the table to another system, perhaps a friend's house or dealer to see if it exhibits the same hum and you would then have your answer.