Orange Drops Priced Outta Sight!

[kheper]

Cornell-Dubilier DPP series:
http://www.mouser.com/Cornell-Dubilier/ ... gfZ1z0yjkz

http://www.mouser.com/ds/2/88/DPP-26740.pdf

[kheper]

Kemet PFR Series Polypropylene Film/Foil, Radial:

http://www.mouser.com/Kemet/Passive-Com ... w3Z1z0wx8w

http://www.mouser.com/ds/2/212/KEM_F3036_PFR-123965.pdf

These caps may not be suitable for hi-fi though. That's all from Mouser...

[dcriner]

These caps may not be suitable for hi-fi though. That's all from Mouser...

What exactly makes a cap unsuitable for hi-fi?

[kheper]

These caps may not be suitable for hi-fi though. That's all from Mouser...

What exactly makes a cap unsuitable for hi-fi?

I'm not exactly sure. I never used them. That's why I remarked "may not be suitable", but:

"electrical ballasts, televisions, video and telecommunications"

I read something about them being used for "surge suppression" too. Who knows? They may sound great.

[Shannon Parks]

Good research, Joe - thank you. I like those Panny ECQPs.

Shannon

[kheper]

No problem. Mouser stocks a few of the Xicon PD series, too.

http://www.mouser.com/Xicon/Passive-Com ... s8Z1yztqfz

[Geek]

I use the Panasonic ECW(x) almost exclusively. They sound good, they're reasonable and my supplier (Digikey) carries them

[dcriner]

Orange Drops no longer exist, except as a name - well, there may be some original new-old stock still stashed here and there. Sprague, the U.S. manufacturer of Orange Drop caps, etc., was bought out by Vishay over 20 years ago. Vishay is nominally headquartered in Pennsylvania, but if you want to know where their products are manufactured, you'll have to phone them - their website is mum.

[Shannon Parks]

I use the Panasonic ECW(x) almost exclusively. They sound good, they're reasonable and my supplier (Digikey) carries them

Same here, Geek. I use them heavily in my Budgie designs.

Shannon

[dcriner]

I often read that Brand X caps "sound great." On what basis? I guess my ears aren't very well calibrated - actually, I know they are not

Caps can have measurable capacitance, leakage, and effective series resistance. Also, voltage rating. What else? But, "How they sound?" Is that quantifiable?

There are many stages within an amplifier or receiver. Can the "sound" of a cap in one stage be discerned from another stage? How?

[Gingertube]

Kemet PFR Series Polypropylene Film/Foil, Radial:

http://www.mouser.com/Kemet/Passive-Com ... w3Z1z0wx8w

http://www.mouser.com/ds/2/212/KEM_F3036_PFR-123965.pdf

These caps may not be suitable for hi-fi though. That's all from Mouser...

Polypropylene Film/foil are excellent for HiFi - I use them all the time.

First - the dielectric.
It used to be Polyester => PolyCarbonate => Polypropylene => Polystyrene in order of performance. (Performance here including stability of value, lower dielectric absorbtion etc.)

PolyCarbonate has disappeared from the market in recent years and been replaced with Polyphenylene Sulphide (PPS).
There is some argue ment that the PPS is so much better than PolyCarbonate that it is even better than Polypropylene, certainly it has superior value stability vs temperature, BUT it is generally not available in higher voltage ratings.

Most Poly caps are "metalized", that is metal is "sputtered" onto the film dielectric, this is a way to get high capacitance per volume as the metal layers are very thin.

Film/Foil is where the metal layer is actual real metal foil. It tends to make the capacitor larger than the "metalized" version but is reputed to be superior for HiFi. This is my experience as well, certainly I use ONLY polypropylene film/foil caps in my HiFi builds.

Having messed about with both Solid State and Tube HiFi at high and low voltages I can give you one big hint on getting good audio performance from a capacitor.
Consider that a capacitor is basically parallel plates with a dielectric betwen them. The plates have an electric field between them and as a result there will be a force tring to make the plates move mechanically. The dielectric prevents this. Weird things happen when the electric field reverses due to mechanical hysteresis in the dielectric.

If you have significant DC across the cap such that the electric field never reverses with the AC signal then you will find that you probably won't be able to tell the difference between a cheap metalized polyester and the most expensive film/foil poyproylene audio "jewellery".

If however there is no signaifcant DC component and the field is reversing with AC signal most of the time, then the difference will stand out the like the proverbial canine testicles.

I redesigned the front end of my Solid State preamp to make sure I had enough DC across the input coupling cap such that the field never reversed. That allowed me to use a 50 cent component instead of a $20 "special".

Cheers,
Ian

[Geek]

I was looking at the datasheets for some PPS caps and their leakage make them completely unsuitable for grid coupling caps, unless they've had a good thousand hour break-in at Vmax

[kheper]

Kemet PFR Series Polypropylene Film/Foil, Radial:

http://www.mouser.com/Kemet/Passive-Com ... w3Z1z0wx8w

http://www.mouser.com/ds/2/212/KEM_F3036_PFR-123965.pdf

These caps may not be suitable for hi-fi though. That's all from Mouser...

Polypropylene Film/foil are excellent for HiFi - I use them all the time.

Of course. Most here (I suspect) use Orange Drops. I was referring to the manufacturer's description in the data sheet for the Kemet PFR series of polypropylene film/foil caps. (See my original post.)

"electrical ballasts, televisions, video and telecommunications"

In the data sheets for other polypropylene film/foil caps, "good frequency response", etc. are mentioned. As I admitted. I never used the Kemet PFR Series, so I have NO idea how they sound.

Film/Foil is where the metal layer is actual real metal foil. It tends to make the capacitor larger than the "metalized" version but is reputed to be superior for HiFi. This is my experience as well, certainly I use ONLY polypropylene film/foil caps in my HiFi builds.

I redesigned the front end of my Solid State preamp to make sure I had enough DC across the input coupling cap such that the field never reversed. That allowed me to use a 50 cent component instead of a $20 "special".

Cheers,
Ian

Amen to the above. You do not need to shell out for a boutique cap, If you are satisfied with a cheap(er) cap.

[Shannon Parks]

Every cap has a purpose. For me in commercial design, the Panasonic ECWs are excellent due to fantastic performance, cost, voltage and capacitance choices, and most importantly, availability. For the diytube designs, I like having the Orange Drops as the main coupling caps as they've been about the cheapest film & foil cap on the planet, highly available and an American classic that most everyone from the guitar guys to datasheet EEs can respect.

A great manufacturer means a lot to the process, too - take electrolytic caps for example. I worry about some of these boutique coupling caps meeting the same standards.

Shannon