Cap question....

[zhivago]

....I'm ordering some electronics from Allparts....

just been checking to see the cap value on the Seymour Duncan schematic and it says .03 cap

but on the Allparts site, all I find is ".033 mfd Ceramic Disc Capacitors"

are they the same?

mathematics say they must be the same thing...but I thought I'd ask.....

[i love sharin foo]

Yep, that's the one. Sometimes they will use Uf for microfarad as well, which is the same as mfd.

Justin

[zhivago]

fantastic!

thanks Justin!

[mezcalhead]

Fair enough to ask, since what they've actually written, mfd, should strictly mean millifarads which would be 1000x greater .. the correct symbol for micro is μ (Mu, but you knew that) .. everyone just seems to use mfd anyway.

IIRC the schematics call for .03, but I've only ever been able to find .033 .. makes no audible difference that I can discern.

[zhivago]

hehe...thanks Jon...I did spend about 30 mins looking round and then decided to post and ask just to be sure!

I'm gathering my order for Allparts, so I can buy all the bits I need at once

[momunist]

i run into this all the time making repairs on vintage gear.  in the past, capacitors were made, sold, and marketed in standard values like 5, 10, 15, 25, etc.  the issue was that most were manufactured to tolerances as wide as +/- %20. that was the best they could do.  so sometime, i think around the 70's they started making them in values so that with the tolerances they were capable of making, the values would overlap.  that's why modern caps will be in values like 22, 33, 47, 63, etc.  there are some companies such as ce distribution that sell caps by certain manufacturers that are made and marked (read: marketed)  to target the old school values such as 20 and 25 rather than 22, 50 rather than 47, etc.  i have used these in vintage amp restorations, but i honestly feel like it's a marketing ploy.  now, i just talk clients about this issue if i'm going to recap a piece of vintage gear, and i usually recomend using the highest quality modern high temp caps available and just finding the closest values.  the high temp versions of modern aluminum electrolytics from xicon and others aren't really any more expensive but will last much, much longer than their predecessors.  often times those, and some low esr versions that weren't available when the vintage gear was designed will lower noise floor, extend low end response, or enhance performance in some way.  i always leave it up to the client, but i personally prefer to use whatever product will perform the best in the application.

[zhivago]

hey thanks for that!

I ordered the parts the caps....now I have to wait for delivery