6922

[fdegrove]

Hi,

Sorry to say so but it's nowhere near to star earthing.

With true star earthing every single negative connection receives its own lead to ground.

Cheers

[marjan]

OK, I do understand that this is not a thrue one point stargrounding, but what are the local stage ground points AIKEN article is talkig about then? PS local ground point, preamp stage ground point... , conected on central star ground point?
Are you saying Frank that this is not a thrue star grounding or you are saying that I made a totall mess out of it, useles for this purpouse? Point me to some basic and not permitable erors please.

Thank you for trying to help

rgds
Marijan

[fdegrove]

Hi,

PS local ground point, preamp stage ground point... , conected on central star ground point?

Everyone seems to have his own philosophy on the matter but to me a single earthing point seems to give to best results.

Since this is a MC Headamp I'd certainly recommend implementing it carefully.

Are you saying Frank that this is not a thrue star grounding or you are saying that I made a totall mess out of it, useles for this purpouse? Point me to some basic and not permitable erors please.

Yes, it's not a true star as you're combining a bus and a star ground in one.
This isn't necessarily an error, it will work, only with a little mre effort it can be made better.

Even without chassis as a shield it should be absolutely humfree.

Cheers,

[Zen Mod]

I'm pretty sure that you can find localy some EI ECC88 or even PCC88 for cheap (hehe-NOS);
for heating I recommend you (even for E series ) LM317 in CCS topology, naturally - elevated to some apropriate potential.
FDegrove have right (almost as usually that you must try fet loaded anodes ;
also-sort of Allan Wright's fet based inputs must be even better-if memory serves me well, 88 can sound little on cold side when is driven with smaller Ub and current.

[marijan]

Well. I supouse I`m not going to bother myself anymore with the MC pre section. After I puted transformers in a seperate enclosure, after I completed the second chanal of preamp, and after I implementd three point stargrounding (all high voltage grounds are conected to the minus pole of first HV filter cap with separate wieres, same at the filament section which is star point 2 and same at the signal circuit-see zipp) I don`t feel any need to change anything. This stuf is realy great. Only noise I can heer from the speaker now is one, produced by my Paravichini tube phono preamp-tube noise at silly gain levels. On the friends SS preamp there is allmost total silence at normal or higher listening levels. I`m shure that fet loaded anodes can sound bether or be quieter in this implementation, same for the one point star grounding, but based on expirience by buildng it using original schematics, I can say it`s fubules anyway. Highly recomended.

I need a chasis now.

rgds
Marijan

[marijan]

in test chasis

[fdegrove]

Hi,

Marjan,

Do you remember when exchanged some mail regarding my MC headamp?

If ever you need one for very low output MCs ( some Ortofons are really very low ouput, for instance) , then this one will provide it.

It does sound sweet and has very good imaging if you use very well selected tubes.

I also select the FETs (BF244A) for IDSS and lowest noise.

I assume you haven't seen it yet here so I post a link to it:

MC HAMMER.

BTW, glad to see the HAMPTON circuit turned out to your liking.

Cheers,