[78-L] Turning the tables

[DAVID BURNHAM]

M. Biel wrote:

 I think that rather than some of the other potential problems David
Burnham mentions it probably was a defective unit that JD had received,
especially since he says that others he had looked at from that brand
did not have a rising and falling turntable during rotation which is
what he said this one had.  That ALWAYS is a defect, and has nothing to
do with acoustic feedback from the speakers

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Dr. Biel is correct, the rising and falling of the turntable when it's rotating is certainly a defect, but I was addressing the flutter in the sound of the recording, and this wouldn't be caused by the uneven turntable.  Just so I could put in my two cents worth of expertise here, I just played an Lp with two pennies under the edge of the record;  this is on a turntable with a linear tracking arm and a Shure V15 type V cartridge.  While the arm rose and fell significantly on every revolution the sound was unaffected.  Of course there could be a problem in the turntable drive motor which could cause flutter but such a problem would be obvious before you even play a record because there would be a vibration felt on the motor board and there would be no need to play the record on another player to compare it as JD said he/she did.  Acoustic feedback will cause a flutter, often at a frequency so low that the sound of the feedback itself can't be
 heard.

db