Capacitors

[bpribadi 0]

Collect some info about capacitors. Everybody is welcome to add

 

European Abbreviation for plastic capacitors:

http://www6.head-fi.org/forums/archive/index.php/t-2718.html

MKP = metallized polypropylene

FKP = metal foil and polypropylene

MKT = metallized polyester foil

MKS = metallized polyester

MKC = metallized polycarbonate foil

FKC = metal foil and polycarbonate

MKI = metallized polyphenylene sulphide

 

ALE = aluminum electrolytic

TAP = tantalum

 

Some knowledge about dielectrics:

http://www.americancapacitor.com/Diel.htm

 

Picking Audio Cap:

http://www.capacitors.com/picking_capacitors/pickcap.htm

 

Sanyo OS-CON:

http://www.semicom.co.uk/manufacturer/sany...n_products.html

Edited October 21, 2004 by bpribadi

[heady 0]

Thanks bpribadi.

 

Perhaps we should have list of shops where we can get particular type of caps from, etc, and make it a sticky as well?

 

[bpribadi 0]

That would be helpfull

[jtfoo 0]

Some tolerance that I can think off.

 

K = 10%

J = 5%

H= 3%

G=2%

 

Not too sure of the rest of the alphabet.

[arj 0]

sorry for my ignorance here...

 

What is the function of a capacitor in amps. and how does a particular capacitor will affect the sound re-production? thanks.

 

\p.s: learning to become DIYer

[jtfoo 0]

Most basic use for audio is in usually two places.

 

1. Power supply reservior. Usually eletrolytic, use to store charges. It smoothen the the DC line by reducing ripples too.

2. DC decoupling aka DC blocking cap. usually placed at input or output of the signal line to block DC. Your headphone or speaker don't like DC as it can kill them.

 

There're other uses for caps in audio, like bypassing power cap(item.1), filtering, crossover in speaker. But simple diyers like me, bypassing is as far as I go.

[domi33 0]

May be somedoby could add comments on which types are preferable for power supply reservoir and which types for DC blocking. I read in parts catalog some ELNA where excellent for liaison, but can't remenber their type.

[bpribadi 0]

Too lazy to click the links heh....

 

For reservoir, only Electrolyte is suitable because of their size of capacity.

 

For bypass FKP, MKP, MKS, Tantalum, Solid Aluminium (OS-CON).

 

For AC coupling, Polystyrene, Polypropylene, Paper Oil.

Edited October 21, 2004 by bpribadi

[huangyong 0]

domi33,

normally, Elna Cerafine Caps are used in Power Supply.

btw, Nichicon's (Gold fuse??) caps are not bad for power supply too.

[heady 0]

huangyong, it is Nichicon FineGold and I like their sound in the CMOYs I built.

[hacknet 0]

i`d like to ake a correction to bpribadi,

 

other caps can be used as reservoir caps. at the moment, my powersupply is 33% electrolyte and 66% MKP. it is possible to use any kind of capacitor as long as proper precautions and measures must be taken to ensure sufficient filtering and voltage stability. as MKP caps come in small values, one can employ things like chokes to aid in the process.

 

another thing i think was mistaken, the DC blocking caps are known as coupling caps. de coupling caps are used in the power supply to lower noise floor and hash.

 

 

for coupling, i`m a fan of stacked aluminium capacitors...

[jtfoo 0]

another thing i think was mistaken, the DC blocking caps are known as coupling caps. de coupling caps are used in the power supply to lower noise floor and hash.

hacky boy,

 

Just do a search on DC decoupling on google. Or take a look at some national chip amp datasheet,e.g TDA7294.. DC Decoupling cap aka DC blocking cap aka ac coupling.

 

You should also know why the decoupling cap on the power supply are also known as bypass cap. It just the word, your choice to decribe which portion as it function, to decouple something or bypass another thing.

[bpribadi 0]

other caps can be used as reservoir caps.

 

You are right, any cap can be used.... but, is it make sense to use small size cap for reservoir?

 

my powersupply is 33% electrolyte and 66% MKP

 

First let me ask, that percentage is by quantity of the caps of by the total capacity ?

 

The MKP in your PS is acting as bypass capacitor not as reservior. I use MKP, MKS, Tantalum, Elco, etc. in my PS, but they are put there for different purpose theoriticaly. Let say you parallel 1 uF MKP with 1000 uF Elco, don't tell me you use the MKP for reservoir purpose

 

What I mentioned above is in general, according to the characteristic of every caps. In fact, you can use any cap for any purpose if you think it is make sense

[hacknet 0]

33% and 66% percentages of values.

MKP was used as the backbone of the reservoir caps because of its low ESR and low noise.

Edited October 22, 2004 by hacknet

[hacknet 0]

there was this great debate on if DC blocking caps were called coupling or decoupling caps. technically, coupling caps are deemed as caps which connect or couple 2 stages, in a tube amp, possibily a driver stage to the ouputstage or a preamp to the power amp, in this case, the amp to the cans.

 

the consenses that the chappies came to was it should be called coupling caps as the importance of the cap was coupling of stages and its main duty was to couple the AC signal between stages. i guess it can be called DC de coupling caps although many of us all it coupling caps...