Bias on EVH 5153 STEALTH

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RG955TT

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Has anyone checked their bias setting on the test points on the back of their Stealth amps? Just wondering what its reading, mine shows 28 mA, how is it reading bias from all 4 tubes? and what should it set at? There is ZERO info in the manual for this, they just say take it to a tech which is BS since there's an adjustment pot and test points right in the back of the amp. Any help would be appreciated, or if anyone would mind checking theirs (super easy, no panel removal, just put multi-meter on red and black test points. Thanks very much
 
I heard first run was 90 mA for all 4 of the Wing C tubes/22.5 per tube.
 
Yes but I have no way of knowing what the test point is reading. I find it hard to believe all 4 tubes are at 28mA total, maybe each but how is it reading this?
This is the only 5153 with test points on the rear panel.
 
hoping to hear about this as well. Someone once mentioned that you pull either the two out or the two inner tubes and test the pair but I don't know if that applies to this amp.
 
Not on the Stealth. How Fender could give you external bias points and external bias adjustment and not give any info on where to set it or what its actually measuring is beyond me
 
Contact Howard Kaplan (the amp designer) by going to either the 5150III Facebook page or go into TGP and PM him. He hangs out both places regularly and answers most questions in less than a day on the Facebook page.
 
If there are 4 bias test points that would indicate that it is one per tube. 28ma would suggest that it is reading one tube. If all 4 of the readings are within 5ma I wouldn't worry. It seems like a low bias to me at 28 but maybe that is how that amp is designed........to run cold.
 
One set of test points (black & red) and one adjustment pot both on rear panel
 
Yep, you better ask Howard, he will help you for sure.
Keep us posted!
 
its probably just using one tube, assuming you have matched tubes ,its approximate...that said just play it and adjust with your ears then check reading if its in the range leave it.. also the range of the pot is probably very minimal//
 
They probably wouldn't have you tapping into the plate and reading for current, but rather the control grid which you would check for voltage. Just a thought. Might be worth a look.
 
Would be great if EVH/Fender at least gave some minimal info on this. Whats the point of having the test points and adjustment w/zero info on what its reading or what it should be set at
 
I think the standard is set around 32 at least mine was when I had it checked a couple of years ago.
 
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