Mesa Blue Angel

[stu]

I just read on Sound Source regarding a Mesa Blue Angel that "you can even use 6L6's in place of the 6V6's as the amp is self-biasing. This can provide more clean headroom if you need it - this is how the amp is set up right now. Self biasing allows you to put any set of tubes in the amp without having to go see an amp tech - this saves you lots of money over the life of the amp and makes quick tube changes in a pinch a lot easier!" Is this true?

 

[musicbox]

absolutely. enjoy it!

 

[stu]

musicbox: I am really nervous about doing it since there is nothing stated in the manual. Can you give me any specific info as to how this won't damage the amp?

 

[musicbox]

No, unfortunately I'm not that well versed in tube circutry. Scan through the Blue Angel Appriciation thread, and you'll find atleast a couple other users enjoying the increased headroom and tightened bottom end found with 6l6 tubes.

My understanding is that the Blue Angel is cathode biased, which means that the biased is not set and cannot be adjusted, it just does so automatically. This is what is refered to as Class A. Keep in mind this is not the same as the fixed bias in a Dual Rec. You cannot simply swap your 6l6 out for 6v6 in a your dual rectifier which is a class A/B poweramp. Because the amp is 'Class A', or some other factor, merely switching a tube out for one that is VERY similare in the way it runs has no negative effect on the amp.

This is not technical fact, and I beg someone to come and lay down the law. What I do know for fact is that this is very safe, and I've been running my Angel with this configuration for 4 months now, usually with the volume pushing 2:00 oclock. If you really don't believe me, call or email a Mesa tech. They'll tell you the same.

SWEET !!

I'm using Ei EL84s, Ei 12AX7s, NOS JAN Phillips 6L6WGBs, & a NOS JAN Phillips 5AR4 in my 4x10....very nice!

I tried the same thing (with the 6L6-for-6v6 tube swap). I heard about it on a forum, got a pair of GT 5881s (rated at about #5), put them in place of the 6v6s.

I got the same results as musicbox: enhanced, tighter bottom end, more top-end shimmer, no flabbiness when pushed into overdrive, more volume and headroom. The power with the 6L6s is about the same as the 4xEL84 setting now. Also, to me it sounds sweeter now somehow- definitely my favorite sound with the amp now.

I don't know if the 6v6s are "warmer" than the 6L6s... less treble response, I'd say, but it's not like 6L6s have too much of a cutting sound. Although, maybe the 5881s are warmer than typical 6L6s?

yep, I did it too. Sounded good.

Though just for your general knowledge the reverse isn't true, a 6L6 amp cannot take 6V6s without drastic modification.