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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
undertow
1,033 posts
 
Honestly very little, unless your motor speed or something seems to struggle... Does not have direct bearing on the actual audio signal, just how the power is regulated to the motor.. I would say it could be a waste if it is working fine, if not I would still not go to some kinda audio costly quality cap, but you could replace if you want. But I could be wrong, my table has a isolated motor that simply has nothing to do with the turntable accept turning the belt at perfect speed, beyond that it does not Hum or cause any ill effect, so if it makes noise or does not run smooth then I guess you could freshen the caps.
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.
kr4's avatar
kr4
3,670 posts
 
It's a 25 year old BSR!!!! Do what you want with it as it was never much of a TT and anything you can get from it (either in performance or fiddling) is worth a try.
zaikesman
3,017 posts
 
"Does not have direct bearing on the actual audio signal, just how the power is regulated to the motor"
That's classic.
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?
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