Need some info on E88CC/6922

[ebijma]

Hello everybody,

I have a question about the E88CC/6922.
Whats the use of pin 9?
You can see in the picture that it leads to some kind of plate
between the two triodes.
Can i connect it to GND for shielding between the triodes?
Or is it ment to do something else?

Hope some of you knows the answer.

Erwin

 

[leadbelly]

http://www.diyaudio.com/forums/showthread.php?postid=207985#post207985

 

[stormy]

Hi,
Its the internal shield seperating the 2 stages and can be
grounded to reduce cross coupling


regards stormy.

 

[SY]

Whether you want to connect it to ground or not is more a function of what you're doing with the two halves. If they're in parallel (e.g., a phono input stage), all that will do is gve you a stray capacitance. If they're in push-pull, it will do no particular harm nor good. If they're in cascade, it can be useful for shielding against unintentional positive feedback.

 

[fdegrove]

Hi,

Further to what SY just posted, if you use one half per channel and you want high channel separation ground the shield as well.
It can give you an extra 10 db of interchannel separation.

The reason it's there is because the 6DJ8 was designed for cascode services.
Later on they added a neutrodynisation cage on one half as well as in the ECC2000.

Cheers,😉

 

[ebijma]

thanks

thanks for the reply's.

Im going to build a vbigc but want to use just one EE88CC.
So in my case im going to ground pin 9.
Thanks for the advice.

Erwin