Music Hall Turntable Hum?


I have a slight hum when I use my phono that increases with volume to the point that when played at loud levels it actually starts feedback with my speaker. I mean bad. System is dead quiet with CD(Music Hall also)I have played ground loop search but think it may actually be something else. Speakers are Def. Tech BP2000 with built in subs and the size of the room and wife dictate the distance I can keep them apart. Are there shielded IC's I could use to prevent the feedback? The MMF5.5 has wall wart plug. Is this EMI? Any help or thoughts would be appreciated. Thanks
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Well, I don't know when the hum becomes audible relatively speaking, but it strikes me that it might also be nothing more than the noise floor of the phono stage interacting with a cartridge with low enuf gain to cause you to crank it up to get sufficient volume. And, perhaps the more obvious, you are initially hearing the onset of feedback caused by excessive volume as a low level hum. Deep bass creates a lot of air movement, some of it subsonic, and that could be causing the TT/Arm/cartridge to resonate. Check this out by listening for hum increase when the stylus is not in the groove and see if the hum increases with volume.

Hope that helps a bit. Solving problems long distance is a bitch. :-)
Thank you Newbee(now I see why I couldn't take that moniker) OK-The hum does increase with volume(stylus off).Can't really hear it at low volumes, but I'd say it "kicks in" around 60% Vol. It then increases notably. It starts as more of a white noise then starts picking up the "hum" as the vol. is increased to around 80% when you can hear it 10' away. With the CD player I can increase the volume to around 90% and not even hear a white noise. Maybe more like air, but no hum. Unpluged the TT and IC's -and no hum from pre. If I take the IC's from the CD player and hook them up to the TT, would that eliminate the IC's from the equation? Don't know where else I can put the TT Thanks again
Sounds to me like your problem is that your cartridge does not have high enuf output for your phono stage. What is the cartridges output? How much gain does your phono stage have? Your complaint reminds me of someone running a MC cartridge into a MM phono stage.
That I do not know. As I said, I should be Newbee. The Music Hall MMF 5.1 comes with the Goldring 1012GX MM cartridge. Unfortunately, that's the extent of my knowledge. The volume differences between the CD and TT are not that far off. There is some difference, but not enough to think that it's because I really have to crank it on Phono. Could it be a bad ground wire that came with the TT? If I disconnect it it REALLY sounds bad(Hum)Sigh...