Other brand EL34 safe bias point?

[Andre Oliveros]

hey guys , i was wondering i own a new set of svetlanas for my old marshall wich its in the bench since forever, so this tubes are branded with a "28" number which the page that i bought them says thats the bias point number, does anyone knows if them are safe to run in the mark V? im just wondering because i will love to try the EL34 just to hear if them suit for me better than the 6L6's thanks guys

Dre.

 

[domct203]

That "28" is only relative to the voltages used by the supplier when he matched the set. The only way to know if they are safe in your amp is to take a bias reading while they are in your amp. Mesa's are biased on the cooler side, around 40% of the tube's max plate dissipation, but the Class A sockets in the MKV are considerably hotter IME.

I would not put them in the MKV without taking a bias reading.

Dom