Suggestions for RIAA Filter Caps?

[thermionic]

Hi,

Having tried a search, there seems to be little consensus on the issue, so I hope you can forgive me for starting another thread.

I'm not so interested in what people think sounds good to their ears - I prefer to make my own mind up, but I would appreciate it if you guys had any suggestions.

The caps I've been using for years have all either been discontinued due to the wretched ROHS law, or the OEM has been swallowed up by a large corporation and parts for audio buffs are discontinued.

I've tried various WIMA PP caps and don't care for them massively.

Panasonic and Vishay MKP-series are ok, but I'm interested in knowing of anything slightly more 'off radar'.

I'd prefer a 1% tolerance if possible. Teflon would be interesting if not too expensive and with tight tolerance.

Any suggestions?

Thanks in advance,

Justin

 

[luvdunhill]

Hi,

Having tried a search, there seems to be little consensus on the issue, so I hope you can forgive me for starting another thread.

what values?

 

[thermionic]

Sorry - I should have made that clear!

Between 1nF and up to 33nF

Thanks!

Justin

 

[thermionic]

BTW - I don't suppose you can get paper-in-oil in tight tolerances can you?


Justin

 

[peranders]

Choose physically small polyprop caps. You can also search for somebody with a good LCR bridge (you could have asked me before (not now) because then I had a 0.025% instrument).

Here you have 1% caps (don't forget to switch to english)
http://www.elfa.se/elfa-bin/dyndok.pl?lang=se&vat=0&dok=2012668.htm
Datasheet
http://www.elfa.se/pdf/65/06545503.pdf

http://www.elfa.se/elfa-bin/dyndok.pl?lang=se&vat=0&dok=2012666.htm
Datasheet
http://www.elfa.se/pdf/65/06510002.pdf

 

[fotios]

A good supplier of any type of Hi-End Audio passive component it is also "Selectronic" from France: http://www.selectronic.fr. It offers probably high quality polystyrene (styroflex) caps of 1% tolerance from 100pF to 18nF and from 390pF up to 82nF of 2,5% tolerance.

Fotios

 

[fotios]

Choose physically small polyprop caps. You can also search for somebody with a good LCR bridge (you could have asked me before (not now) because then I had a 0.025% instrument).

Here you have 1% caps (don't forget to switch to english)
http://www.elfa.se/elfa-bin/dyndok.pl?lang=se&vat=0&dok=2012668.htm
Datasheet
http://www.elfa.se/pdf/65/06545503.pdf

http://www.elfa.se/elfa-bin/dyndok.pl?lang=se&vat=0&dok=2012666.htm
Datasheet
http://www.elfa.se/pdf/65/06510002.pdf

Hi Per-Anders

After an extensive search for 1 year ago, finally i resulted in three online stores:
1) From ELFA.SE i order polypropylene foil capacitors either SCR or WIMA and LCR.
2) From Farnell Export.UK i order electrolytic capacitors, polystyrene LCR, and silvered mica caps.
3) From Selectronic.FR polystyrene (styroflex) caps, silvered mica, and the difficult to find WIMA miniature MKP2 from 10nF to 100nF at 100V.

Fotios

 

[thermionic]

Thanks for the suggestions guys - much appreciated.

P-A - are you suggesting I use small caps to prevent parasitic noise pickup? A pro designer I know criticises me for this reason if I use a larger cap than necessary. I took some advice on this issue @ Bruno Putzeys' forum, and a member showed a picture of a Sony valve-microphone, where Sony had fitted a screening can around a large cap to prevent noise.


Justin

 

[peranders]

Small caps tend to have better HF properties, such as resonance frequency.