E88CC preamplifier _ I need diagram

[panterka]

Bye .

I have 3 lamp E88CC Tesla, I would want to build preamplifier on them very, but not I can nowhere find best's diagram on them. I think, that working preamplifier would be best solution in class A, necessarily without transformers on exit.

I ask about help.

pa_nterka1@o2.pl

[Colt45]

search for preamp designs using 'ECC88' or '6DJ8'. E88CC is special version of these.

[fdegrove]

Hi,

Thank Claudio Bonavolta for this little collection:

6DJ8 PRE

Ciao,

[Brett]

Wrong tube for a lineamp IMO/IME; too much gain.

[fdegrove]

Hi,

Wrong tube for a lineamp IMO/IME; too much gain.

Agreed, but this is Poland, the man's probably happy to have a few fine tubes already....

Cheers,

[li_gangyi]

hey...it could be used to make a pretty good headphone amp as well...well maybe it's not his original intention...but just an idea...

[fdegrove]

Hi,

hey...it could be used to make a pretty good headphone amp as well...

It would be a better headphone amp than it would be a linestage for a cd source for sure...

Not that it would be the universal headphone amp either...

Cheers,

[li_gangyi]

but...he needs a pre-amp...not a headphone amp...

[fdegrove]

Hi,

but...he needs a pre-amp...not a headphone amp...

That doesn't really matter....

We have six triodes to work with and are fortunate to have the E88CC which has a shield between the tube halves.

Assuming we use 1 + 1/2 tubes per channel we can build a fine preamp which will have too much gain for a CDP but with the output stage in PP will have sufficient current capability to drive anything from longish lengths of cable to a moderate Zin headphone set.

What comes to my mind is a Morgan Jones headphone amp that uses, IIRC, an anode follower direct coupled into an SRPP or was it a WCF or CCF?.

Anyway, the gain's provided by the first stage, the next is there for current drive.
The latter is always a good thing to have in a preamp especially when you want to drive low impedance loads, even if it's only occasionally.

Having too much gain isn't necesarilly a bad thing, there is a matter of what's too much though.
In this case I feel it passes just about fine and for the following reasons; the E88CC is a medium µ twin triode with a Raeq of 300 Ohm, it has lowish Ri providing low Zo and the spare gain can help dynamic range.

The latter also keeps the stage from having to work too hard which keeps distortion figures low.

Having only 3 E88CCs to work with, that's about the best I can come up with.

There's more that can be said about it but this is basically what you need to keep in mind.

Cheers,

[jevta]

Hi,
I can suggest for make phenomenalny line preamp with both sections E88CC per channel. I have had used last 3 years and after comparated for other line think that is good preamp. This preamp ensure gain 23 . It's glory "Daniel schema". Another, I can say that was hit in last 5 years in Serbia. Most of DIY made own version because is very simple and extra have possibility for future upgrade.
First for discuss is tube. On market have more than 5 manufactures. Many say that Telefunken, Siemens and RCA are for discution what is best but don`t forgot for Philips and Ei and all other like Amperex,Svetlana, Tesla... All my Friends ( momentaly 4 ), audiophile maniacs have had use this preamp. Creation is very simple. Tubes work in parallel mode line stage. Idea this hidden in ultrastabilized anode voltage on 265 V.
Second part for discussion is OP amp in anode circuit for ultrastabilation anode voltage. Many used AD825 or AD711(my favorite) or Burr Brown palete OP series.
Third of course output cap and PS, atenuator all el.parts.
Originaly, PS is seperate from preams