Is bipolar capacitor ok to replace polarised?

[cretaceous]

I'm fixing my old Musical Fidelity stereo amp and replacing all electrolytics
But I must have ordered the wrong capacitor type for 5 of them as they are marked BP - which Google tells me is bi polar.

Am I ok to use these or should I get normal polarised electrolytics?
- they are 1uF caps.

thanks

 

[underwurlde]

Where in the circuit are they used?

 

[cretaceous]

thanks for reply
2 in the pre amp and 2 in each channel of power amp (6 total)

there's a hand drawn schematic here:
Musical Fidelity A1 - Technical

but I can't really see which are the 1u caps...

 

[Juergen Knoop]

polarised electrolytics behave like bipolar ones, if the DC/signal level is small enough and some designers get away with it.
However if the MF designers choose bipolar ones, they are propably right and you shouldn't mess it up!

 

[underwurlde]

C6 & C7 and yes, they should be fine to use there

...but they could colour the music and then we start getting into a whole different discussion!!

Can't see the other 1uF, so can't comment. What was the designators on the PCB for the 1uF caps?

Andy

 

[cretaceous]

no designator on PCB , just a + symbol (it's nearly 30 years old..)

not a big deal I guess.. I can go to Maplins next week but I wanted to finish it this w/e

many thanks guys

 

[underwurlde]

Cool. Make sure you match the voltage then, 50V I believe - and go for good quality if poss as they are directly in the signal path.

GL

A

 

[cretaceous]

yeah the BPs were 50v
but how do you know what is a "good quality" cap?
I guess that's been answerd in other threads !

(and now I read that film may be better than electolytics these days...??)

 

[underwurlde]

Books could be written on this subject! And yes, s-loads of info on this forum.

look on maplin website & search for '1uf'.

Good choice would be the metalized polyester film ones (for the signal path C6 & C7) or if space permits, the audio grade polypropylene ones.

A