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jrhymeammo
05-07-2005, 09:00 AM
Have been into Vinyl for about 2 yrs now, and now I'm getting to notice the background buzz. It is not so much noticeable when just turned on. But when I move the tonearm to the near surface of LP, when everything is turned on, the sound is more obvious. I have been informed that the feedback problem is very common and mind boggling issue. My Rotel receiver is only capable of 75 ws at 0.03% noise.So, it may be that I am playing it much louder than intended. Also, my Powered Sub would sometimes start flopping and would not make any sound. But it would make play violently around 20 hz; Iam just making this assumption since it is very hard for me to hear the sound but instead I would only feel it on my body. I would appreciated if any of you Vets know any possible solutions to this. Oh, to clarify more none of tyhe problems I've listed above happens when playing from a digital source. Thanx much in advance for your future replies.

risabet
05-07-2005, 11:20 AM
Have been into Vinyl for about 2 yrs now, and now I'm getting to notice the background buzz. It is not so much noticeable when just turned on. But when I move the tonearm to the near surface of LP, when everything is turned on, the sound is more obvious. I have been informed that the feedback problem is very common and mind boggling issue. My Rotel receiver is only capable of 75 ws at 0.03% noise.So, it may be that I am playing it much louder than intended. Also, my Powered Sub would sometimes start flopping and would not make any sound. But it would make play violently around 20 hz; Iam just making this assumption since it is very hard for me to hear the sound but instead I would only feel it on my body. I would appreciated if any of you Vets know any possible solutions to this. Oh, to clarify more none of tyhe problems I've listed above happens when playing from a digital source. Thanx much in advance for your future replies.

Does the buzz happen only when the TT motor is running? Does it get louder as the arm moves across the record towards the label? This doesn't sound like acoustic feedback, but more like hum. If you place the stylus on a still record do you get feedback through the speakers? Grados are unshielded and are known to suffer from this problem. I am not familiar with your TT but if the noise gets louder as the arm approaches the label it's probably magnetic hum.

The flapping sub is possibly caused by your Arm/cartridge resonance being at the wrong frequency, too low? which drives the sub with subsonic signals.

jrhymeammo
05-09-2005, 01:11 PM
Hey risabet, you were absolutely right about the sound near the center of records. I guess that's why more expensive TTs have motors located away from the source. I also moved the Phono Pre-amp least 18" away from any electronic devices. That was a huge improvement. I found out that bass flapping came from my TV. Thanks.

risabet
05-09-2005, 02:22 PM
How did your TV cause the woofer flapping?

squeegy200
05-09-2005, 10:02 PM
Have been into Vinyl for about 2 yrs now, and now I'm getting to notice the background buzz. It is not so much noticeable when just turned on. But when I move the tonearm to the near surface of LP, when everything is turned on, the sound is more obvious. I have been informed that the feedback problem is very common and mind boggling issue. My Rotel receiver is only capable of 75 ws at 0.03% noise.So, it may be that I am playing it much louder than intended. Also, my Powered Sub would sometimes start flopping and would not make any sound. But it would make play violently around 20 hz; Iam just making this assumption since it is very hard for me to hear the sound but instead I would only feel it on my body. I would appreciated if any of you Vets know any possible solutions to this. Oh, to clarify more none of tyhe problems I've listed above happens when playing from a digital source. Thanx much in advance for your future replies.

Sometimes the TT motor causes interference with the cartridge pickup. As mentioned earlier, this was often the case with Grado Cartridges but can be experienced with other makes as well. If you have a mat on top of your platter, some would place tin foil underneath the mat. The aluminum foil would serve to shield the cartridge from motor interference.