Capacitors for MM phono stage loading

[Ammonite Audio]

What type of capacitor is best for use across the input of a MM phono stage? My phono amp uses little Wima polyprops, but I need to tinker with different values and wonder if polystyrene caps might be better in terms of tone and musicality?

Any thoughts and experiences would be much appreciated.

[Reffc]

I'd stick with good quality polyprops Shuggie. Something like 5% Claritycap ESA's work fine in that application. The effects on tone of various cap types is over rated imho (although it's generally accepted bad practice using electrolytics in the signal path). Tolerance, correct rating and reliability are more important generally.

[Ammonite Audio]

I should clarify that these are the MM cartridge loading capacitors, in the region of 100pF to 200pF, depending on the capacitance of the tonearm cable, so the ESAs are just too big in terms of value and bulk. It may be that my Audio Note AN-Vx silver litz tonearm cable provides the necessary capacitance loading without anything added at the phono stage, while the Audio Origami (Van Damme) cable is low capacitance so a bit more is probably required on top. That's why I need to experiment.

[DSJR]

Loading caps go across the load, so hopefully shouldn't make a sonic degradation. SME used tiny ceramic caps in their old leads I remember, although this type is frowned on for such audio uses now I believe.

Can you get polystyrene caps of the right capacitance?

[Ammonite Audio]

Loading caps go across the load, so hopefully shouldn't make a sonic degradation. SME used tiny ceramic caps in their old leads I remember, although this type is frowned on for such audio uses now I believe.

Can you get polystyrene caps of the right capacitance?

Yes - HiFi Collective sell a good range of them in axial packages, but I see that Farnell also do LCR polystyrene caps (http://uk.farnell.com/lcr-components/exfs-hr-100pf-1/capacitor-100pf-63v/dp/9520180) in little radial packages that appear to have the same lead pitch as the Wimas already in the phono amp.

[anthonyTD]

Yes - HiFi Collective sell a good range of them in axial packages, but I see that Farnell also do LCR polystyrene caps (http://uk.farnell.com/lcr-components/exfs-hr-100pf-1/capacitor-100pf-63v/dp/9520180) in little radial packages that appear to have the same lead pitch as the Wimas already in the phono amp.

hi Shuggie,
I would go for the polystyrene ones, they are often used in timing circuits so good tolerance and performance' a good choice for this purpose.
Anthony,TD...

[Ammonite Audio]

Excellent - thanks Anthony!

[YNWaN]

I use styrene loading caps in my own phonostage and this is not uncommon.

[NRG]

+3 for polystyrene's...

[Rare Bird]

i used to use Suflex Polystyrenes & Oscons.

[337alant]

http://www.ebay.co.uk/itm/Wima-FKP2-Series-Polypropylene-Capacitors-100v-100pF-to-10nF-Packs-of-4-/130832457334?pt=UK_BOI_Electrical_Components_Suppl ies_ET&var=&hash=item1e7638de76#ht_506wt_1161
http://www.ebay.co.uk/itm/8-X-SOSHIN-100pF-500V-SILVER-MICA-CAPACITOR-/251063870913?pt=Vintage_Electronics_R2&hash=item3a7492a5c1#ht_1035wt_1419

http://www.ebay.co.uk/itm/5-x-Polystyrene-Capacitor-Axial-100pF-2-1-2-30V-/380644536321?pt=UK_BOI_Electrical_Components_Suppl ies_ET&hash=item58a02eb001#ht_196wt_1399

http://www.ebay.co.uk/itm/Qty-10-Silver-Mica-Military-Grade-Capacitors-Ten-Silvered-Mica-Caps-Various-/120846778897?pt=UK_BOI_Electrical_Components_Suppl ies_ET&var=&hash=item1c23078211#ht_1006wt_1161




Alan

[Rare Bird]

I dunno about your last link, i don't think id use a 5-10% tolerance cap in my Phonostage EQ!

[337alant]

I'd go for the Wimas or polysyrene myself ;) in fact they are a good buy so I have just ordered some 100, 220, 330, 470pf wimas myself
Never tried a silver mica in that position TBH but they are very stable caps and 5-10% isn't a bad tolerance by cap standards just match a couple up.

Alan