Elna cerafine bypass??

[audiocrow]

My arcam alpha 7SE have an output coupling capacitor - a 10uF electrolitic Elna cerafine. In my tweaks i've tried to bypass it with a polyester 100nF Philips capacitor. It's a shame that I can't get rid of those coupling capacitors...but without them:5V offset

I've made some listenings with and without the bypass capacitor and I just can't decide:

With bypass capacitor: sound seems a bit more treble extended but I don't really precise if it's just extra distortion/harsh or is in fact extra revelations...
Yeah...I know metal film capacitor would be the best but low €€€ present!

Thank you for your time.

[VS]

Hi,

Even the "cheapest" metalized polypropylene capacitor
would do a better job than the polyester ! Don't use
polyester in audio (in coupling and signal bypassing).

A simple MKP from WIMA is an option for a very low budget...

[audiocrow]

Thank you VS.

I see you are also Portuguese. Where do you get those kind of capacitors? And by the way : how the hell can you distingue between polyester and metal film??... (felling dumb )

I really thought that a metal film capacitor is something like a multicap, or those cousins- costing around 90€?!?!?!?

Thank you for your Time...

[nuppe]

Well, yes and no...

The multicap is a metal film cap, but what VS suggest is that you use a metalized polypropylene film cap. The difference is a metalized film cap is manufactured by depositing metal onto a plastic and then wound. The metal film caps are made using two (or more) layers of film, plastic and metal.

Generally the film types are more expensive, but are considered to be better performers (something to do with pinhole noise in the metalized variants, i can't remember exactly right now). Polystyrene is considered to be the worst (AFAIK) of the plastic dielectrics, and polypropylene among the better.

MKP (metalized polyprop.) types are generally a good cost/performance compromise, if you don't feel like shelling out the $$ for film caps. Also there are "standard" non-audio manufacturers of film types that won't cost you an arm and a leg. The special audio brands are sometimes insanely expensive by comparison. Wether it might be worth it i cannot say...

Check out Walt Jung's How to pick Capacitors, part 1 ; part 2 it is very informative. It might be a tad on the technical side, but you don't have to understand everything that's said (i sure don't ) to get a good guideline for picking capacitors. The end of part 2 sums it up pretty good, so skim the first part if you're not interested.

/Andreas

[VS]

Originally posted by audiocrow
Thank you VS.

I see you are also Portuguese. Where do you get those kind of capacitors? And by the way : how the hell can you distingue between polyester and metal film??... (felling dumb )

I really thought that a metal film capacitor is something like a multicap, or those cousins- costing around 90€?!?!?!?

Thank you for your Time...

Hi ! Yeah, a Portuguese fanatic

Well, regarding to your questions, a polyester capacitor is also a film capacitor ! MKT is a comum label present in the capacitor package meaning "Metalized Polyester".

You could buy a MKP "Metalized Polypropylene" capacitor by as low as 1 euro or even 80 cents, however a good audiophile "version" will cost you much more, in general above 10-20 euros, and it depends on the voltage - choose a high voltage type since it gives a better sound (>200V, 400 or 630V preferred). With a very reasonably price you could chose one of these (Mundorf) starting at: http://www.schuro.de/mcap.htm.

If you want to spend as little money as possible go just to a good
electronic shop and ask for a Polypropylene Capacitor (MKP) and test it right away!

Regards,
VS

PS: where do live ?

[VS]

Regular one's that you can find "easly" in Portugal .....http://www.wima.com/navig/pr.htm


Hi Nuppe,

Do you agree with this classification ?

1st - MKP
2nd - Polystyrene
3rd - MKT (or MKS)
4th - Electrolytic

[audiocrow]

A portuguese from Lisbon.


Well i'm going to learn how to choose capacitors ...

Be right back

Thanks

[nuppe]

Originally posted by VS
Regular one's that you can find "easly" in Portugal .....http://www.wima.com/navig/pr.htm


Hi Nuppe,

Do you agree with this classification ?

1st - MKP
2nd - Polystyrene
3rd - MKT (or MKS)
4th - Electrolytic

I'm definitely no authority on the subject, but yes, I think that about sums it up. If MKP or Polystyrene should be first i don't know, but both are supposed to be very good. Polystyrene
are harder to get hold of though.

/Andreas

[Tube_Dude]

Originally posted by VS


Do you agree with this classification ?

1st - MKP
2nd - Polystyrene
3rd - MKT (or MKS)
4th - Electrolytic

Hi VS

I will change only the first two.

1º- Polystirene
2º-Polypropylene
3º-MKT (Polyester)
4º-Electrolytic
5º-Tantalums

Um abraço

[VS]

Hi,

Ops...the first is really Teflon !

Ok, in fact there is some discussion about polystyrene and polypropylene...but the "first" is disappearing and also I never see any document stating that is was best than polypropylene…

Do you have any "source" document ?