input coupling capacitor VALUE & BRAND for mono LM4780

[nickthevoice]

Hello !

I have many questions !

I built mono gainclone with LM4780 Peter Daniel KIT with 50K ALPS volume control. (my source is CD player)

*I want add coupling capacitor but what VALUE 1uF or 4.7 uF or 2.2uF ?
and what BRAND ? (easy available in Canada). SOLEN 250v Metallized Polypropylene sounding great or not ?

*I view many people put WIMA MKP 470pF capacitor to ground after the coupling capacitor it's noise filter ???

*it's great idea to add ZOBEL filter with WIMA cap on this amp or not ???

*what's the best resistor type for upgrade sound quality of this KIT ?
exemple: change all for 1% tolerance or change for all carbon film ???

thanks in advance !!!

nicK

[nickthevoice]

okay you need exemple :

if I create Gainclone LM4780 only with two brand.

HOLCO or DRALORIC for ALL resistor
and
ELNA Cerafine & ELNA LPO for ALL capacitor.

the result will be what ? better sound Q than original DIY kit ?

thanks !

nicK

[ygg-it]

May be usefull to read:

Input Capacitors for Headphone Amps by Warren Young

http://tangentsoft.net/audio/input-cap.html
http://web.engr.orst.edu/~brownth/CouplingCap.pdf



Use the following formula:
C> 1/ (4* PI* R)

[danielwritesbac]

Originally posted by nickthevoice
Hello !
. . . I built mono gainclone with LM4780 Peter Daniel KIT with 50K ALPS volume control. (my source is CD player)
. . .I want add coupling capacitor but what VALUE 1uF or 4.7 uF or 2.2uF ? and what BRAND ? (easy available in Canada).
. . .I view many people put WIMA MKP 470pF capacitor to ground after the coupling capacitor it's noise filter ???
. . .what's the best resistor type for upgrade sound quality of this KIT ?
nicK

One input filter cap is documented by Audiosector, and that's Blackgate N 4.7uf. Since that's a "known good" then I'd find one.
Other capacitors can provide a different variety; however, pricepoint doesn't relate to success, and brand doesn't relate to success.
The most expensive method is to make random selections. If you do that, try a small collection of "favorites" because that's closer to a "known good" than a random selection.

RF cap: The capacitor that you often see added in parallel to the input impedance resistor, is to block RF. That can be helpful to restrict the amplifier to ampifying only audio. As for myself, I use a 3 cent ceramic 330pF.

Best resistor types (as in "known good" components) are documented at the Audiosector web site.

Best, in of itself, means "application specific" not brand nor price.

If you continue to have trouble, suspect an impedance mismatch between amplifier and source. Use a preamp/buffer to fix that.

[nickthevoice]

THANKS !!!