Stupid question for the bias mod gurus...

[dudleydawson]

...so i picked up my LSC with the bias mod a few months ago. i knew i would need a replacement set of power tubes soon - but i was really hoping to wait it out until the spring (TAX TIME) - but i'm getting all kinds of trouble and need to do it now.

with the holidays here - i'd rather spend the disposable income on the kids then my basement habit... so i'd like to get a set of tubes before i have to bother with picking up a bias probe/multimeter just yet (the setup i'm looking at is ~$80 - that's 2 nintendo games!)

the amp currently has mesa yellow 6L6's... and the literature i got with it says it was set to 65% of max plate dissipation - (37 mA i think).
should i be confident that picking up new mesa yellows will be appropriate?
i know that they are 'factory set' with a lower bias - what i do not know is what kind of range the mesa tubes have - so i want to confident that i wouldn't risk going too far outside the 'normal' parameters...
seems to me that the acceptable tube characteristics which mesa normally considers ok for a 'colder' amp might put me into trouble since i'm running hotter now.

i'm also not committed to Mesa tubes... i plan on dropping Doug's an email to see if they can accommodate me with the little amount of information i have.

i know the right answer.... get the bias probe. but my kids have been pretty good this year...

 

[BobL]

Dudley,
The bias being set for 37ma has no bearing on the issue at all. The bias will change when you change the tubes. I just now posted some info in response to another thread you may wish to read. Regardless, any tube will work as long as you set the bias within the tubes specs when you change them. It's a catch 22 Dudley. Buy the kids the games and live with the tubes you have for a while.