Overdrive Special, Steel String Singer, Dumbleland, Odyssey, Winterland, etc. -
Members Only
Moderators: pompeiisneaks , Colossal
talbany
Posts: 4696 Joined: Tue Mar 28, 2006 5:03 am
Location: Dumbleland
Post
by talbany » Mon May 11, 2009 4:49 pm
If I recall I have 434v on the plates. When I did the voltage chart it was pretty much in line with what others were getting.
It is biased at around 40ma.
Tom
I know everybody has there magic # at where they bias there tubes...
For me Iv'e found the 6L GC have a smoother transition into grind if they are biased @ 70% max plate dissapation... @ 40ma to me is a bit on the cold side.. Try running them up to around 48... Give that a try and see if you like it better...
http://www.webervst.com/tubes1/calcbias.htm
Tony VVT
Structo
Posts: 15446 Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon
Post
by Structo » Mon May 11, 2009 4:51 pm
Thanks I will.
I was going by what many here said about the D amps liking the bias a bit towards the cool side.
But you are right, I should experiment with the setting.
Tom
Don't let that smoke out!
Structo
Posts: 15446 Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon
Post
by Structo » Mon May 11, 2009 4:57 pm
Wow, according to the top calculator on the Weber page, my 6L6's should be biased at 61ma for 70%!
Tom
Don't let that smoke out!
talbany
Posts: 4696 Joined: Tue Mar 28, 2006 5:03 am
Location: Dumbleland
Post
by talbany » Mon May 11, 2009 5:07 pm
Tom
That sounds like class A.. Your amp is Class AB.. Try that..
Tony VVT
Structo
Posts: 15446 Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon
Post
by Structo » Mon May 11, 2009 5:09 pm
I did.
I have class AB, 6L6GC, 343v = 61.2ma
If I move down to the next calculator I enter 343v and 61ma it comes up at 20 watts, but it also lowers the bias to 58ma.
If you look at the bias charts down below for a 6L6GC, at 350v it lists 60ma for 70%.
Tom
Don't let that smoke out!
talbany
Posts: 4696 Joined: Tue Mar 28, 2006 5:03 am
Location: Dumbleland
Post
by talbany » Mon May 11, 2009 5:11 pm
If I recall I have 434v on the plates. When I did the voltage chart it was pretty much in line with what others were getting.
It is biased at around 40ma.
I thought you said the voltage was 434...
The charts below are for Cathode bias amps...
Tony VVT
Structo
Posts: 15446 Joined: Wed Oct 17, 2007 1:01 am
Location: Oregon
Post
by Structo » Mon May 11, 2009 7:29 pm
talbany wrote: If I recall I have 434v on the plates. When I did the voltage chart it was pretty much in line with what others were getting.
It is biased at around 40ma.
I thought you said the voltage was 434...
The charts below are for Cathode bias amps...
Tony VVT
Ah geez, not enough sleep last night....
Yes 434v
Sorry
Tom
Don't let that smoke out!