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Capacitors in line with TT motor - Upgrade?

I am doing some major upgrades to a 25 year old BSR turntable, such as going to a MC cartridge, rewiring the tonearm with Cardas wire, adding mass to the platter, replacing the flimsy plastic base with a massive (40 LB) plastic block, removing the motor from the sub-chassis mount and attaching it instead to the massive base, etc. When I pulled the motor out, I noticed it had two capacitors in circuit with it, a 5000pF ceramic, and a 1.5 uF cap made of hard white epoxy-looking material (not sure what type it is). Would it be a good idea to replace these with new caps? Would upgrading the quality make any difference to the motor's performance? Any help is appreciated.
ait

Showing 4 responses by ait

ait OP
480 posts
 
The motor does vibrate a bit when running, so I will probably replace the caps and see if that helps. I am isolating the motor from the sub-chassis in order to minimize vibration, so I might as well go a little further and get new caps.
ait OP
480 posts
 
I realize it was never a top-of-the-line unit, but it's a challenge to try to make it into something good, that I can use for a year or so until I buy a top notch TT. I think that the changes I'm making will elevate the performance to at least middle-of-the-pack among TTs.
So, back to the Caps - the small ceramic disk is to drain the RFI generated on motor startup to eliminate the turn-on thump, and the other is used to regulate the motor speed. I'll probably leave the ceramic disk alone, since they last forever, and replace the other with a good quality mylar film cap - any reasons not to use a mylar film, other then it probably being a bit of overkill?
ait OP
480 posts
 
Zaikesman,

You state that you increased the capacitance, I'm just curious why. I was intending to just replace the cap with a better one of the same value, is there a benefit to increasing the capacitance, and if so, what is the benefit?
ait OP
480 posts
 
OK, let me rephrase. Is your motor DC or AC? Mine is AC synchronous, and as such uses the 60 Hz frequency of the AC from the wall to regulate the speed. I don't really have a power supply per se, just the power cord and the caps. I think that if I change the value of the caps, I will change the speed.
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