first attempt at phono preamp, will this work?

[av-trouvaille]

Well, once started searching this came along, with attached schematic of a tubed capacitor multiplier:
http://www.wduk.worldomain.net/forum/showthread.php?t=704&page=3

To the right of the schematic you will notice the ripple killer as discussed in the previous posts. Before the ripple killer and after the choke is the stage of capacitor multiplication.

The description of James_D on 30th April 2006 encouraging the diy'er is:
‘ Post 22: Be prepared for it not to work!!! I haven't built a Class A2 series reg before so I'm not 100% confident that I have it right - on paper it appears sound but that doesn't mean I haven't got it wrong!!!
And post 26: the series reg is basically a capacitance multiplier circuit as in terms of reducing hum ripple it is as effective as a cap the value of the cap connected to its grid multiplied by the voltage gain of the valve. James’

Have fun, Arjen.

 

[Shoog]

I messed about with simple silicone cap multipliers with both a Zen amp and a preamp. In both cases it introduced a definite sonic signature. I removed it from the preamp, but had to leave it in the Zen.
Personally if I had the choice I would leave well alone.

Shoog

 

[av-trouvaille]

Shoog, could you elaborate some on the nature of the sonic signature?

Arjen.

 

[Shoog]

We are talking 5 yrs ago so not really. If I had to hazrad a guess it would be bloated.

Shoog

 

[fdegrove]

Hi,

Think impedance and you'll likely understand why capacitance multipliers using valves aren't all that popular.

It's the same problem with valved regulators be that series or shunt.
You want to isolate the circuit from the mains supply, you want capacitance without the sonic signature of electrolytics...

Tell us what you want to achieve and I'm sure people can help.

Ciao,