Quote:
Originally Posted by Ed in Tx
Is it the original cartridge?
MM cartridges need a certain amount of capacitance for a flat freq response. The maker will typically spec the loading at 47K Ohms and some capacitance between 200-400 pF. The low capacitance cables like mentioned before really came into play in the '70s with the old CD-4 records with frequencies up to 50 kHz that needed 100 pF and 100K Ohms load to work right. With that CD-4 loading a typical stereo cartridge would usually sound bright.
Some turntables have a mute switch that operates while the arm is moving and landing on the record so you don't hear that initial noise of the stylus finding the groove (or lifting at the end). That could explain why you don't hear the hum until the record starts playing.
I assume there are no components with big transformers, or fluorescent lights nearby that could be inducing hum. And you have the separate ground wire and it's connected.
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Hi, I have the original Owners manual and Service manual for this record player that I downloaded from Vinyl Engine shows that the original phono cable that came with this turntable was a 150 pF capacitance cable.
As for the cartridge that's currently on this turntable is a Shure M92 LT cartridge and the owners manual for this turntable says specifically that this turntable can use whatever P-Mount cartridge you wanted with it as long as it was rated to be used with a linear track turntable.
And as for whether or not there's any florescent lighting or equipment with large transformers nearby, that would be a big no.
Unless you count the power transformer in my Pioneer SX 1000 TD Stereo receiver.
Which if that's the case then, whats the point of using a record player that's going to be susceptible to the power transformer in your receiver?
Because last I checked most stereo receivers of good merit (50 WPC+) have pretty decent sized power transformers in them.
And yes I do have the ground wire connected and as I stated before, its not because of the ground wire, because the hum is the wrong frequency and also the record player doesn't hum any other time except for when the record is playing, and the "no ground wire connected" hum would happen regardless of whether or not the record was playing or not.