Capacitors and hype!

[boiss]

A capacitor has capacitance!
A capacitor has some Inductance due to it's construction but this is generally negligible?
A capacitor has resistance minimal but it's there!
A capacitor has Carisma?
A capacitor can be full of ******** and cost more than an O/P transformer?
Any thoughts and proof!!!
Mike

[Colt45]

A person can be stupid and buy them, too.

[anatech]

Hi Mike,
I think you need to focus your question some more. The response from Colt45 points out the underlying issue, although I'd call those people more "misdirected" than stupid.

Is your problem with the advertising of the product, or the reviewer drivel? Something else?

-Chris

[kevinkr]

Call me stupid... I dare ya!

All capacitors have inductance, depending on construction it can be very significant..

All capacitors have non-linear dielectrics without exception. DF and DA are the two major measures of such effects.

Did you know the nature of the termination at the end of the foil or metalization in a film cap can have an effect on linearity as well? (Think of as many as three different metals, and not perfectly hermetic seals.)

Finally having spent many years with cheap capacitors I came to realize that certain types of "improved" and expensive capacitor seemed to sound better, I'm referring primarily to teflon dielectric types - they're never cheap but milspec surplus seem to work about as well as the exotic brands. (Russian made surplus teflons offer a lot of bang for not so many bucks.)

In many cases these were gifted to me for various reasons - so there was no economic incentive for me to hear an improvement, and in the face of a fairly strong desire not to spend more on this already expensive hobby.

Electrolytics are even more complex to discuss as although there are lots of well understood performance downfalls - why is it that no one explains why some well respected brands of large value electrolytics generate huge amounts of distortion at very low signal voltages? (Low impedance cathode bypass for example)

My preference runs to:

Teflon/foil
polystyrene/foil
paper in oil/foil
polypropylene/foil (sometimes in oil, like tuna.. )
metalized polypropylene

Yes, the advertising copy associated with exotic capacitors is pure bunk, however most of these capacitors are made by well regarded capacitor manufacturers and actually represent nominally above average capacitor performance in DF/DA and other areas. It would be great to get good quality caps without paying for the name, but sometimes it is hard to know what you are getting, and for that reason I often fork over relatively big bucks. My fav over the last 4 yrs has been the teflon based Vcap which wins in my system for transparency over a lot of other equally expensive capacitors.

Make yourself a little test jig and actually listen to a bunch of capacitors, you may or may not find you hear any difference. Should you not hear any difference just use the cheapest thing you can get.

[ray_moth]

Mike, have you read Morgan Jones's Valve Amplifiers? He goes to some lengths to exlain this subject and it's worth reading.

[anatech]

Hi ray_moth,
I can't disagree. That book should be a must read for DIY people. It doesn't matter if you don't use valves, the ideas are presented clearly and the book is a very easy read.

Hi kevinkr,
I agree with what you are saying. Often times it's more the capacitor family that is important. Not the name on the outside. The bang for the dollar comes into play as well. $200 dollar caps are just plain silly, even if they may seem to sound better. Even $20 for a smaller cap is outside what I'll spend.

Paper in oil/foil caps. I don't trust them. Sorry.

Foil tends to handle higher currents well, so they are for power supplies or speaker crossovers mostly. Nothing wrong with film as long as it's thick enough and is not carrying higher currents. They may open if used in zobel networks or for supply bypassing.

One last point. Often, newer electrolytic caps may be better quality. I find that the larger case volume is a better cap for the same value. That is a generalization that may not always hold.

Are your findings similar Kevin?

-Chris

[kstagger]

I've just started using cheap Russian Teflons and honestly I prefer them over MIT RTX, Auricap, Wima, Wondercap, etc. Another inexpensive cap I prefer to use is the Obbligato stuff.

[TubeHead Johnny]

IMHO:

The brand name isn't important. What matters is the dielectric.

Poly F/F are a nice balance between cost/performance, although higher value/voltage units can be very large.

Metalized types tend to sound too bright, even after many hours of break-in.

For compensation networks, polystyrene is the best. Mica I avoid as well....they tend to sound harsh.

I my experience, oils seem to roll off the treble.

[kevinkr]

Originally posted by kstagger
I've just started using cheap Russian Teflons and honestly I prefer them over MIT RTX, Auricap, Wima, Wondercap, etc. Another inexpensive cap I prefer to use is the Obbligato stuff.

Yeah, they are very good, and the price of admission is right. Removing the metal can around them reportedly is a revelation, but alas I am too cowardly to try it..

I find the RTX bright and harsh sounding, and I don't think it is just revealing the short comings in the amplifier circuitry it is connected to - I think it is adding something to the sound. I will say it was an absolutely huge improvement over the CDE WMF types I used previously.

I've heard good things about the Obbligato as well. For X-O I find the Clarity SA Cap to be hard to beat. It's sold by a lot of vendors, but I generally get mine from Madisound.

[kevinkr]

Originally posted by anatech
Hi ray_moth,
I can't disagree. That book should be a must read for DIY people. It doesn't matter if you don't use valves, the ideas are presented clearly and the book is a very easy read.

Hi kevinkr,
I agree with what you are saying. Often times it's more the capacitor family that is important. Not the name on the outside. The bang for the dollar comes into play as well. $200 dollar caps are just plain silly, even if they may seem to sound better. Even $20 for a smaller cap is outside what I'll spend.

Paper in oil/foil caps. I don't trust them. Sorry.

Foil tends to handle higher currents well, so they are for power supplies or speaker crossovers mostly. Nothing wrong with film as long as it's thick enough and is not carrying higher currents. They may open if used in zobel networks or for supply bypassing.

One last point. Often, newer electrolytic caps may be better quality. I find that the larger case volume is a better cap for the same value. That is a generalization that may not always hold.

Are your findings similar Kevin?

-Chris

Re: The paper in oil, the only ones I have used in recent years have been Jensen brand or other brands oem'd by Jensen, and they have been very reliable in the 10 or so years I have used them. Frankly I have seen physically small mylars that had higher leakage current than these. So far no problems, but I much prefer the "sound" of teflon to these paper caps which sound a bit slow and euphonic to me..

My general experience matches yours very well in fact as do my opinions. Nothing to disagree with here..

Your comments on the electrolytics parallel my recent experience, and I tend to use the 63V rating in Nichicons almost exclusively now because they have a much lower loss tangent angle than a comparable lower voltage cap, and the larger physical case sizes in the higher voltage ratings are even better in most cases. I still prefer any BG in the audio path if I can get my hands on one, for supply use I generally stick to the Nichicon as mentioned...