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gerard
03-06-2005, 12:08 PM
hi

I have seen caps 100volts are non polarized and cheap.

what about the 400v solen , 630v audiocap etc ..., are those caps polarized or not .( no - sign ? ) .

I need to change 3.3 uf caps polarized on my amplifier , can i use solen ones or will it explode ?

Gerard

Mr. Widget
03-06-2005, 12:30 PM
You can replace a polarized cap with a non polarized (assuming correct voltage etc.), but not the other way around.

Widget

Zilch
03-06-2005, 12:34 PM
Film and film and foil type capacitors are inherently non-polar, and thus have no polarity designations on them. They are larger and more expensive than polarized capacitors of equivalent capacitance in aluminum eletrolytic or tantalum types, and are used for different purposes.

"Non-polarized" capacitors are generally inexpensive aluminum electrolytic types, and, if used in the signal path for coupling or filtering, are not the best choice in comparison to film or film and foil types. An amp manufacturer would use them for those purposes only because they're cheap, most likely.

Non-polar capacitors such as you cite can usually substitue for polarized types without a problem, but it's a waste of money unless you are certain of the function of the capacitors in the circuit, i.e., that they ARE in the signal path and not just power supply filtration. If not, replace with like polarized types. Amp designers usually knew what they were doing when specifying components.

Why do you "need to change" these? Because of some failure, or are you just hoping for some improvement?

gerard
03-06-2005, 01:06 PM
ok

I Want to change those caps because they are more 20 years and may be it can decrease the sound quality .
I wonder if those caps were not use as bypass ? it is the only caps unless 20 uf on my amp ( mitsubishi) ... so I told myself i could use audio caps like dayton or solen 400v ...

gerard

Zilch
03-06-2005, 04:24 PM
At 3.3 uF, either the Dayton or Solen would be fine, we're only talking a couple of bucks, if they will fit, physically.

I would not be investing in Kimber Kap or Audio Cap, no.

Me, I'd just replace in kind what's in there. If they're aluminum electrolytics, I might use tantalum, instead, is all....

gerard
03-07-2005, 01:36 AM
Zilch , thank you but I want to be sure before it explode .....

Can i change a 3.3 uf polarized caps in my amp by a dayton 3.3 uf 400vac even it is not polarized ????.

Regards

gerard

Guido
03-07-2005, 03:45 AM
Gerard, it's as Widget posted:


You can replace a polarized cap with a non polarized (assuming correct voltage etc.), but not the other way around.

Widget

hector.murray
03-07-2005, 05:31 AM
And after a long time, changing electrolytic caps is a good idea as they dry out. Ounce of prevention beats a pound of cure ( couple cheap caps replaced beats changing blown VC as the result of DC to the coil).

Zilch
03-07-2005, 10:15 AM
Yes. It will not explode.