I received this amp about a week ago and noticed that the bass was not as tight and coherent as I thought it should be.
Anyway, I spent hours today trying to install the new caps only to find out that the factory caps are tamper proof, and cannot be removed by any conventional means as the fasteners are cemented together.
I want to possibly attach a set of 18,000uf 75v caps to the originals for now if there are no issues in doing so.
My other issue is that the legs on the ceramic snubber cap for the rectifier failed so it is no longer attached. It is a .1uf Z5U @ 20% (M). I have no idea what the minimum voltage should be rated at for this amp.
Anyway, I spent hours today trying to install the new caps only to find out that the factory caps are tamper proof, and cannot be removed by any conventional means as the fasteners are cemented together.
I want to possibly attach a set of 18,000uf 75v caps to the originals for now if there are no issues in doing so.
My other issue is that the legs on the ceramic snubber cap for the rectifier failed so it is no longer attached. It is a .1uf Z5U @ 20% (M). I have no idea what the minimum voltage should be rated at for this amp.
I've seen 5 to 10nF 600V ceramic caps on occasion.
Something like these:
https://www.radio741.com/65272-001uf-10nf-600vdc-radial-ceramic-disc-capacitor-z5u.html
Something like these:
https://www.radio741.com/65272-001uf-10nf-600vdc-radial-ceramic-disc-capacitor-z5u.html
I want to smooth the hell out of this bugger so that there is absolutely no ringing. Is 1uf going to do it, or is .1uf enough?
Can I use a film cap?
Can I use a film cap?
OK. A web search indicated that I should stick with the stock value ceramic do it being the best cap for the job.
Both 0.1 and 1uF seems too high IMO. I'd search for 0.01uF rated at minimum, for twice the DC across lytics. Example, if you look for 60VDC, thus take 200V caps. For ringing to be properly elliminated, an oscillocope is needed.
.1uf is the stock value, so thats what I ordered. The original electrolytics are 10,000uf @ 75 volts. The replacements are 18,000uf @ 75 volts.
Why would the voltage rating need to be increased?
Note that I am talking about wiring the caps together in parallel, not in series.
Why would the voltage rating need to be increased?
Note that I am talking about wiring the caps together in parallel, not in series.
Last edited:
So parallel is additive in capacitance and voltage where series divides? The original caps are wired in series which would yield less than 10,000uf total unless these are AC.
And if these are DC caps, this amp does not have enough capacitance for bass reproduction even when new!
And if these are DC caps, this amp does not have enough capacitance for bass reproduction even when new!
It’s the snubber caps that need to be higher rated. They need the same voltage rating as the RECTIFIER, or more. The DC plus the peak reverse voltage when off, plus margin for surges.
At an rate, I am going to have to modify the cap connection from serial to parallel in order to have enough capacitance.
What would the voltage handling requirement be.
What would the voltage handling requirement be.
Not unusual either. A higher rated cap is less likely to fail. Also will “keep” all its capacitance. Class 2 ceramic caps have lower capacitance at full voltage. They work sort of like ferrite inductors saturating, but not quite as nonlinear.
Paralleling the new reservoir caps with the old ones will work but maybe not as a long term solution. You can certainly see if that’s what’s troubling the amp, but I wouldn‘t leave the old ones in there to eventually fail in a more dramatic way. Eventually you need to find a way to get the old ones out.
Paralleling the new reservoir caps with the old ones will work but maybe not as a long term solution. You can certainly see if that’s what’s troubling the amp, but I wouldn‘t leave the old ones in there to eventually fail in a more dramatic way. Eventually you need to find a way to get the old ones out.
I actually have 4 of the new caps, so I figure if I wire 2 banks of them, each of the 2 wired in series, and then connect them in parallel to 2 3-connector blocks it should work?