Screen Grid Resistor values on early Mark amps

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MK IIB

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Hi folks.
Does anyone know why Mesa nearly always used 5% tolerance 470 ohm (Gold band) carbon comp screen grid resistors in the 60 watt(2 x 6L6) amps but mostly always used 10% tolerance(Silver band)for the 4 x 6L6 (Non Simul Class)100W amps?
I've got 10% tolerence 470 ohm CC's screen grid resistors in my Mark 2B 60 watt amp as it's all I could get at the time and was wondering if this would make any difference or cause any problems?
From looking at gut shots etc Mesa nearly always used this configuration so it must mean something or does it?
Any help is much appreciated.
Thanks folks.
 
You can do your own "tolerancing" if you are concerned. Buy a bunch of them and measure them with an ohm-meter (multi-meter). Any that are within 5% of 470ohm (446.5 - 493.5) are 5% resistors. The 5% or 10% applies to the batch - all it tells you is that a big bag of those resistors will measure within the tolerance of the value stated.
 
jhreid said:
You can do your own "tolerancing" if you are concerned. Buy a bunch of them and measure them with an ohm-meter (multi-meter). Any that are within 5% of 470ohm (446.5 - 493.5) are 5% resistors. The 5% or 10% applies to the batch - all it tells you is that a big bag of those resistors will measure within the tolerance of the value stated.
I get that.What I'm wondering is why Mesa choose the 5% ones for 2x 6l6 amps and 10% for 4 x 6L6 amps?
 

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