Silver Mica for bandwidth limiter

[harvardian]

Does anyone see a problem (audible) with using a Silver mica 220pF cap for use as a bandwidth limiter in an active filter.

 

[Nelson Pass]

I regard Silver Micas as the best cap you can get
as long as it holds the value tolerance you want.

 

[harvardian]

Thanks!

Hello Nelson,

Thanks again for your very timely post and help.
Glad to have you out in the ether...

Best Regards,

Dale

 

[Bernhard]

Hi,

isnt it a problem that the silver micas are magnetic ?

There are non magnetic mica versions too.


Bernhard

 

[fmak]

silver mica

Why use this when there is plenty of choice of pp film and polystyrene capd available. To me these sound better unless you but the very expensive Soshin ones.

 

[Jocko Homo]

Nelson:

Have you been talking to Paul McGowan again? [joke]

Jocko

 

[alaskanaudio]

There is nothing wrong with using mica caps.

Small value silver mica caps are excellent compensation caps to control high frequency roll off or to provide high frequency boost in most any applications. I use silver micas for such use in all of my designs in which I can keep the capacitor valued below roughly 220pf. In applications where higher capacitance values are required and extremely good characteristics into the upper VHF frequency range is not required then I prefer to use polystyrene types.

Don’t use ceramic types under and circumstances in the signal paths since they can produce strong harmonics when AC currents are flowing through then.

John Fassotte
Alaskan Audio

 

[Nelson Pass]

Sorry, the joke appears to have passed through
one of the holes in my consciousness without being
apprehended.

 

[HarryHaller]

McGowen and silver micas

Paul McGowen was a fan of silver micas. I guess Mr. Pass's knowledge off his contemparies feedback preferences may not extend to capacitors. To be fair, capacitor preference is a rapidly moving target in audio. Jocko hates them because the tempco goes all over the place and he is an old ham radio guy that built circuits that can't drift with temperature for radio applications. They do have low ESR and series inductance but have lousy D.A. perfomance and temperature stability. I like polystyrenes sound better and my local surplus store has a great stash of small P.S.(and silver mica) caps.

H.H.

 

[Jocko Homo]

Was a fan?

As far as I know, he still is. Haven't talked to him in quite a few years, but I doubt he has changed much.

Jocko

 

[Elso Kwak]

Soshin Silver Mica Caps

Hi Fmak,
You do have experience with the Soshin Silver mica's ? I was considering these for the KWAK-CLOCK.
Recently I acquired a Escort ELC-131 capacitance and inductance meter that can measure the Q and dissipation factor of a cap. I had laying around some Soshins salvaged from old equipment and they measured better; higher Q, lower D, than other silvermica's.
I know THL in Taiwan carries them at <B>VERY</B> steep prices.
Do you have a better source?😉

 

[fmak]

Re: Soshin Silver Mica Caps

Hi Fmak,
You do have experience with the Soshin Silver mica's ? I was considering these for the KWAK-CLOCK.


Yes, I have used them for years. The SE is very expensive but sounds excellent as feedback or filter caps. They are terminated with flat leads and molded.

The FE version is coated with round leads and is the version you see in high quality Japanese equipment. They sound more rounded and 'ordinary ' to me, but perhaps better than the magnetic types which I routinely remove.

I have a small stock of FEs and some SEs, and may be able to help you out.

While I am on, can you do a post on relative merits of waveform in clocks. Why are some stock designs clean sine waves as opposed to not so clean square waves in 'improved' versions. And why are the latter better.

I want to replace the 45 MHz clock on Sony SACDs as an experiment.

Fred