PICKING CAPACITORS

[Hoerninger]

Steve Bench:

The Sound of Capacitors - Capacitor Linearity **Expanded**
http://greygum.net/sbench/sbench102/caps.html


____________
Peter

[scott fitlin]

well im a carbon freak
capacitors on a oil carbon base improved my sound considerably.

the vintage equipment (in my opinion) has more character than modern stuff.
a friend of mine replaced all resistors that were carbon based with metal films. we compared and now hes soldering everything back.
but technicaly it measured better. but the old amp lost its soul.
the 1801 poweramp by bose.

in speakers and also cd players ive got improvements.
i dont understand what you mean by grade
the specifics should be the same but the brands are different.

this is also the case with coils. remove the ferriet/iron core and make them bigger. so teh centre is air.

ME TOO! I LOVE CARBON COMPOSITION, has a certain sound.

Capacitors? I agree, some of the vintage items have a sound that is special, IF they haven't worn out or shifted too terribly.

In my crossovers hi frequency sections, I replaced two metallized film caps, with modern remakes of an old style film cap, MUSTARD CAPACITORS! typically, these are used for musical instrument amplifiers, and offer a unique coloration characteristic I find quite desirable. Makes the highs sound creamy, and sweet. Very much the way certain tube amps sounded, as well as a few SS designs.

www.sozoamplification.com

[Hoerninger]

An Improved SPICE Capacitor Model by Steven M. Sandler.

I hope that this simple subcircuit will help to separate fact from fiction, and may also find itself as auseful tool in the selection of capacitors for switching power supply designs.

http://www.aeng.com/pdf/Capacitor.PDF

Improved Spice Models of Aluminum Electrolytic Capacitors by Sam G. Parler, Jr.
www.cde.com/tech/impedance.pdf
____________
Peter

[Hoerninger]

Lynn Olson, 2002:
Towards perfection - building a better Capacitor:

http://www.nutshellhifi.com/library/capacitor.html
___________
Peter

[jcrobso]

http://waltjung.org/PDFs/Picking_Capacitors_1.pdf

http://waltjung.org/PDFs/Picking_Capacitors_2.pdf
______________
Peter

I remember reading them very carefully back then. Nice to read them again.
I think that a lot of high grade audio caps we have today are a result of these articles in Audio.

[1audiohack]

In the "Towards Perfection - Building a Better Capacitor" article I take exception to a couple of statements;

Aluminum is notoriously easy to oxidize, acquiring a film minutes after it's removed from an acid-etch cleaning bath.

Many aluminum alloys are easily oxidized, pure aluminum happens to be very corrosion resistant, it's just not very strong.

although relaxation and re-orientation of the grain structure might be possible as well. For transformers, the cause is fairly obvious: the stress of winding the wire fractures the grain structure of the wire at each bend around the winding former, and it takes weeks or months for the winding stresses to be relieved.

Well, no, first off virtually all copper wire is pulled down to size, pre-stressed before it's even spooled. One very curious property of copper wire is that if you take a length of it (single strand) and measure it's diameter end to end and then stretch it, and measure it again you will find that it reduces in diameter from end to end with astonishing precision, no thin spots, no lumps. This is in part due to the fact that copper has a body centered atomic stucture... I have tried to figure out how to explain in print how these bodies are bound together and the complex way they distribute strain forces through the structure unlike the lattice structures of steel and will have to find some pictures if anyone is really that interested.

Suffice it to say that copper does not have a grain stucture that seperates and then heals, it's more like a "chinese finger" (the woven cable type like you pull wire with) when you pull on it, it changes dimension without suffering any damage. Like that yet with another dimension added to it.

[Progneta]

A while back I talked to some individuals who told me to try some oil caps. In short I never did......Well after digging through my shop I found some old JAN radio stuff. I found that the caps were the perfect value for the hi freq portion of my 2-way setup (Altec 288 and 515b). They are from the 60s so I put them on my LCR meter and found they are reading perfect. So I rigged up my setup with the oil caps w/ a bypass cap and YAHOOO does it sound good!!!! I am still experimenting with different caps but oil caps give me a real life sound....beautiful!....scrap the low cost caps ehehehhe...... I do want to try some Duelund CAST-Cu Copper/Paper-in-oil caps....but the wife factor gets in the way........maybe when she is gone I will have them scheduled for delivery! hahaha

-G

[jcrobso]

In the "Towards Perfection - Building a Better Capacitor" article I take exception to a couple of statements;



Many aluminum alloys are easily oxidized, pure aluminum happens to be very corrosion resistant, it's just not very strong.



Well, no, first off virtually all copper wire is pulled down to size, pre-stressed before it's even spooled. One very curious property of copper wire is that if you take a length of it (single strand) and measure it's diameter end to end and then stretch it, and measure it again you will find that it reduces in diameter from end to end with astonishing precision, no thin spots, no lumps. This is in part due to the fact that copper has a body centered atomic stucture... I have tried to figure out how to explain in print how these bodies are bound together and the complex way they distribute strain forces through the structure unlike the lattice structures of steel and will have to find some pictures if anyone is really that interested.

Suffice it to say that copper does not have a grain stucture that seperates and then heals, it's more like a "chinese finger" (the woven cable type like you pull wire with) when you pull on it, it changes dimension without suffering any damage. Like that yet with another dimension added to it.

Copper wire is made by pulling it through a die, the molecules realign in the process.
However the more you work copper the harder it gets, so it must be annealed.
Annealing is done buy heating up the wire and then let it very slowly cool back to room temp.

[1audiohack]

Copper wire is made by pulling it through a die, the molecules realign in the process.

UhUh, there are no molecules in metal, nothing in the structure is that large!

All the rest,, yup.

[jcrobso]

UhUh, there are no molecules in metal, nothing in the structure is that large!

All the rest,, yup.

Some people are just so picky.

[Hoerninger]

http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf

____________
Peter

[Hoerninger]

"John Curl is one of the most respected circuit designers ..."

Read more about amp design including dielectric absorbtion:
http://www.parasound.com/pdfs/JCinterview.pdf
____________
Peter

[tomt]

I think that a lot of high grade audio caps we have today are a result of these articles in Audio.

the jung-marsh article had a huge influence.

Some people are just so picky.

'crystal structure'

oil caps give me a real life sound....beautiful!....

vitaman q does a (musical) body good -

[Mr. Widget]

John Curl...

Thanks Peter...

I just read it. A very interesting read.

I must admit, I am a bit of a fan. I have several of his pieces... reading about the thought and process behind his work is enlightening.


Widget