So I'm doing a recap for an older onkyo integra m-5060r
changing the older electrolytics with new quality ones and then I noticed they have two 220pF polystyrene caps , one for each channel in the signal path I assume.
Does anyone know whether these polystyrene caps age as badly as others especially electrolytics or can I just leave them alone , the amp itself is something like mid 1980's I think so its somewhere in the 30 to 40 year age period.
I'm asking because it seems it is quite hard to get polystyrene these days and would a quality polypropylene metalized film cap be just as good given the values match and tolerance is 2.5% to 5%?
changing the older electrolytics with new quality ones and then I noticed they have two 220pF polystyrene caps , one for each channel in the signal path I assume.
Does anyone know whether these polystyrene caps age as badly as others especially electrolytics or can I just leave them alone , the amp itself is something like mid 1980's I think so its somewhere in the 30 to 40 year age period.
I'm asking because it seems it is quite hard to get polystyrene these days and would a quality polypropylene metalized film cap be just as good given the values match and tolerance is 2.5% to 5%?
Leave them alone as they do not age like electrolytics. They were probably selected and matched for tolerance, (or at least the manufacturer may tell you they are selected), finding replacements will not improve the amplifier.
polystyrene caps are today replaced by pps and fkp.Some of the old polystyrene (copper foil) are simply golden...They only age with temperature and light.Light isn't coming inside and usually they are placed far from the heat sources, so they might be very good even after 100 years of use. As you can see they are quite expensive nowadays:
https://uk.farnell.com/lcr-components/fscex-220pf-1-630v/cap-220pf-630v-1-ps-through-hole/dp/9520716
RS PRO Polystyrene Capacitor 220pF 160V dc +-2.5% Tolerance Through Hole 4mm diameter | RS Components
If there's no hum , i would first check the quality of the original electrolytic capacitors because there's a great chance to find out that the older capacitors are better than the new ones!
I would check first LCR and Rifa for polystyrene.
https://uk.farnell.com/lcr-components/fscex-220pf-1-630v/cap-220pf-630v-1-ps-through-hole/dp/9520716
RS PRO Polystyrene Capacitor 220pF 160V dc +-2.5% Tolerance Through Hole 4mm diameter | RS Components
If there's no hum , i would first check the quality of the original electrolytic capacitors because there's a great chance to find out that the older capacitors are better than the new ones!
I would check first LCR and Rifa for polystyrene.
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I think you are dreaming. Epoxy seal electrolytics were only used to my knowledge in fender guitar amps. How are the tires on your 1982 Mercedes? Elastomers age due to oxygen, used or not.
One can buy 600 22 uf caps for the price of an ESR meter from Peak.
OTOH, one can buy 10000 hour rated small e-caps these days.
well I was asking because I'm changing the older 220nF caps to new polypropylene ones and I just thought I could change these too but since I can't find any good enough replacements for these and RS PRO I don't count as exactly a good analogue then I will leave them alone for now for someday in the future when I will have enough spare bucks to also change out the old power supply filter electrolytics .
for now IO measured and they show close to rated capcitance so I will just leave them for now.
for now IO measured and they show close to rated capcitance so I will just leave them for now.
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