Found a pair of these in a storage box, can't find the datasheet for this exact model but they are used in ceiling fans. The manufacturer's site just mentions "Metallized Polypropylene or Polyester film", but which one is it no one knows 😎 Probably equivalent to CBBs. I have been using oil-immersed motor-runs for a long time, they sound good for power supply filtering but are rather large. Interested to hear if anyone used these boxed types and if they sound good, because they would make for a more compact design - or am I losing my time on them.
Series' page on the manufacturer's site
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What are CBBs? As for the caps, they could work in power supply applications. As for high frequency performance, that's a big question mark since ESL, ESR (equivalent series inductance, resistance) are not specified for them since for use at 50/60Hz, those parameters are too insignificant to worry about. Manufactures of those caps would have no need to optimize those parameters. At audio frequencies, they could be significant. Only way to know for sure would be to try them, measure them, and see what results you get.
CBBs are metallized polyprops seen everywhere on ebay. I think "orange drops" used in guitar amps are of this type too. I use them in non-signal applications, like snubbers and in regulators.
I agree ESR/ESL for these probably won't be great. I wouldn't dream of using them in signal path as coupling caps for example, but being in PS filter operating at 120Hz will these lack luster parasitics be significant? In a SS amp a low ESR is very desirable because they operate at higher currents, but I don't know if it is as critical for tube gear operating at sub-ampere levels.
Thanks for the informative reply. I still wonder what the letters stand for. Maybe they don't stand for words at all but are just much like a part number or designator, I dunno.
This is from https://medium.com/@mia.pinge/the-difference-between-cbb-capacitor-and-cl-capacitor-2b63250eecfd
The ever popular 715 and 716 series polypropylene capacitors (i.e. "Orange Drops") are technically CBB capacitors.
Call me old fashioned but I like good sounding electrolytics in PS. None of my attempts to use film caps, even very expensive ones, left me satisfied.
If you have access to the caps it's trivial to determine polyprop or polyester from the tempco.
If you have access to the caps it's trivial to determine polyprop or polyester from the tempco.
I'm interested to know how one goes about determining this. Measure capacitance while heating the cap with an hair dryer? I'll check for tempco data on the interwebs, if you have some handy that would be great.
I think the C-D type 715P and 716P are both film and foil types, rather than metallized. Not a big deal for audio, of course.
All good fortune,
Chris
All good fortune,
Chris
Does an ice chest, a lamp, a fan and an inkbird heating/cooling thermostat count? Probably not but if you ever need to hatch a few eggs...
Power supply capacitors do not sound , good or bad, but if they are too small (such as these) you will have lots of ripple.
Which sounds bad.
Honest opinion? Yes.
See above.
If you like, please describe good sounding caps vs bad sounding ones, that will be interesting.
Feel free to use your own adjectives.
These are Motor Run capacitors.
Forget mild work inside amplifiers, they are connected to Mains lines where lightning can (and does) hit transmission lines regularly
As in many times during any electrical storm.
Protection devices (spark gaps, high power varistors) limit that to 1000 or 1500V peaks at user lines, but anyway ...
Plus motors are very inductive and "sparky", again generating large peaks.
So any "250VAC" rated capacitor does NOT mean just the sinewave peak 300 something Volts but a MUCH higher peak value.
By heart I remember they were tested at 1600VDC or so but apparently modern test rating is even higher.
Test voltages are mind boggling:
WAY above 250VAC peak value (354VDC) as imagined above.
Industrial/machinery World is very different from HiFi needs and ratings
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Motor start/run capacitors are basically just robust versions of standard film capacitors - just about always with a polypropylene dielectric for the required temperature range. The square ones are of the usual stacked construction while the large can types are rolled and the can filled with oil (typically mineral oil) to enable the required power dissipation level.
PSU caps have just one reason for being, that is to keep ripple voltages as small as possible...
Ripple voltages are directly proportional to load current and inversely proportional to C..
electrolytic capacitors have fluids inside that can leak and evaporate with time, they can dry up...
the solid polymer electrolytic caps are a definite improvement of sorts, but i am not sure if they are available in the 400 to 550 vdc ranges..
cbb62 are shrinking in size...i have used them in my builds and i am happy....
Ripple voltages are directly proportional to load current and inversely proportional to C..
electrolytic capacitors have fluids inside that can leak and evaporate with time, they can dry up...
the solid polymer electrolytic caps are a definite improvement of sorts, but i am not sure if they are available in the 400 to 550 vdc ranges..
cbb62 are shrinking in size...i have used them in my builds and i am happy....
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Modern, quality electrolytics will pretty much outlast anything they are installed in, especially if you go with a 105 degree version. Unless, of course, it is in a badly designed system where they are installed in hot areas right next to pass transistors or regulators - unfortunately way too common. The polymers aren't available in higher voltages unfortunately.