shielding may not be necessary
I just finished mine last week too (wood DIY tonearm). Fighting the hum up to yesterday and finally eliminated it
If you want to shield anyway, a ground wire (connected the chasis of the turntable and then connected to the ground terminal at the preamp) can be wraped around the four signal wires from cartridge for shielding. After all, putting the wires inside of the wood arm wouldn't give better shielding anyway. So you can do it outside of the arm. It has been suggested that the - wires (blue and green) be connected to this ground at the preamp, not at the turntable ground.
But then, I found (for my case) that my arm didn't need shieldling at all when I earthed my ground by connecting the ground terminal of the preamp to the water tap in the bathroom (through a 3 meter long wire). The noise, hum, all the annoying sounds are all gone.
Just an alternative...
Nui
I just finished mine last week too (wood DIY tonearm). Fighting the hum up to yesterday and finally eliminated it
If you want to shield anyway, a ground wire (connected the chasis of the turntable and then connected to the ground terminal at the preamp) can be wraped around the four signal wires from cartridge for shielding. After all, putting the wires inside of the wood arm wouldn't give better shielding anyway. So you can do it outside of the arm. It has been suggested that the - wires (blue and green) be connected to this ground at the preamp, not at the turntable ground.
But then, I found (for my case) that my arm didn't need shieldling at all when I earthed my ground by connecting the ground terminal of the preamp to the water tap in the bathroom (through a 3 meter long wire). The noise, hum, all the annoying sounds are all gone.
Just an alternative...
Nui
Hi,
Keep in mind that alot of MM and MI carts have one of the negative legs connected to the body of the catridge internally making them useless for balanced inputs.
With MCs this usually not the case so the are good candidates for a balanced input.
Cheers,
balanced right off the MM cart must have a good CMRR. I would like to try converting my single ended turntable into balanced.
Keep in mind that alot of MM and MI carts have one of the negative legs connected to the body of the catridge internally making them useless for balanced inputs.
With MCs this usually not the case so the are good candidates for a balanced input.
Cheers,
Hi,
Not so easy to do on most but you may get lucky...
The easiest ones are those on which the tie to ground is run at the outside of the cartridge body.
I can't guarantee you they won't buzz like a yellowjacket in the wind once that ground is disrupted though.
You'll need a good TT with good magnetic shielding of the motor too.
Cheers,
I can try to find a cartrige and then modify it if possible too.
Not so easy to do on most but you may get lucky...
The easiest ones are those on which the tie to ground is run at the outside of the cartridge body.
I can't guarantee you they won't buzz like a yellowjacket in the wind once that ground is disrupted though.
You'll need a good TT with good magnetic shielding of the motor too.
Cheers,
Hi,
Yup...
Cheers,
then you really
should have a 5th wire running to the cartridge shell
Yup...
Cheers,
Hi,
How true...
Fortunately it doesn't apply here since the arm beam isn't hollow.
One thing to take care of is proper dressing of the armwiring so that it doesn't interfere with the arms' movement or anti-skating.
Cheers,
That can be a real pain, believe me.
How true...
Fortunately it doesn't apply here since the arm beam isn't hollow.
One thing to take care of is proper dressing of the armwiring so that it doesn't interfere with the arms' movement or anti-skating.
Cheers,
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