[holdemxpert]

I recently inherited this amp, which was shipped across the country to me, no users manual and cant find one online.
 
 It came with 6 tubes. 3 were in plain white boxes marked 1, 2, 3 (which I assume was intended to correspond to the positions on the amps deck, front to back?).
 
1- Ken-Rad 6SN7GT  VT231
2 and 3 - Sylvania 6SN7GT  VT231
 
The other 3 are electro-harmonix 6SN7EH in original boxes "Made in Russia".
 
 
Are these tubes all the same and placement doesnt matter, or if there is a difference am I correct that the order would have the Ken-Rad in the front?
 
(The headphones that came with it are Sennheiser HD650s.)
 
Thanks in advance

 

[diego]

That amplifier uses 6sn7s in all positions. The first socket is for the input tube and the other two are for the output tubes so it is better to use identical tubes on those sockets.

 

[holdemxpert]

Thanks Diego. Is there any reason he would have had a Ken-Rad and two Sylvanias? He never bought anything electronic without a reason!

 

[Frihed89]

Probably because the KenRad was being used as the driver.  It will add a little more than bass to the Sylvanias.  This is a nice amp, but don't use it to drive current hungry headphones.  Be careful in that regard.  Stick with something that is relatively high impedance.  At the time these were made the Senn 650 was the headphone of choice, but anything with a rated impedance of around 100 ohms or more will probably be fine.
 
Good luck.