Ceriatone Forum

British Style => JCM 800 2203, 2204, 2550, 2555 => Topic started by: Jimmy on June 15, 2009, 05:52:46 AM



Title: 6n2p-ev tubes in preamp 2204
Post by: Jimmy on June 15, 2009, 05:52:46 AM
Hello!
I want to install in a Ceriatone 2204 amp in all preamp positions 6n2P-EV tubes. I got a schematic that shows what to do, because the 6n2P-ev tube can only handle 100 Volt in the Cathode follower position. Can someone explain me how to install this?
Thanks



Title: Re: 6n2p-ev tubes in preamp 2204
Post by: cmoore on June 15, 2009, 07:07:53 AM
I really have no idea, but....
Where did you get the drawing from?  Is it a working creation, or just theory?  It seems pretty straight forward.  I guess the idea is to lower the B+ to the preamp so you do not burn up the tube in the cathode follower position.  I guess a 12ax7 can take about 200 volts in the cathode compared to just 100 for the 6N-2P.
Don't mean to waste your time, this is kind of over my head, but why make the change?  Is there some advantage with the octal pre tubes, have you heard this circuit before?
Seems like there should be more info.  For example, what value components do you use to bias the 6N-2P?  What about the rest of the circuit for that matter; like grid/plate resistors and coupling caps?  Do you stick with the same tube all the way through the PI ?
You may already know all of this stuff.  I sure would be interested to know what all of this adds up to.
Thank You and Good Luck


Title: Re: 6n2p-ev tubes in preamp 2204
Post by: Jimmy on June 24, 2009, 12:31:38 PM
So i tried 3x 6n2p-ev Tubes in the Preamp of my Ceriatone 2204. They sound really great! This is what do (see pics): YOu have to solder your tube sockets like the pic shows (6,3Volts) and you have to install the Caps (but i used a 22uf or 100uf instead of the 10uf). It works great!


Title: Re: 6n2p-ev tubes in preamp 2204
Post by: cmoore on June 26, 2009, 06:02:19 PM
What would you say the advantage is in switching to these tubes?
Thank You


Title: Re: 6n2p-ev tubes in preamp 2204
Post by: Jimmy on June 26, 2009, 07:13:32 PM
The 6n2p-ev tube is a better quality high selected ecc83 (12ax7) tube (made for russian millitary/used in MIG 29 plains). This tube sound really amazing and they are cheap instead of the ecc83 tubes.  ;) i switch all amp to them.