I am trying to set the bias on my Bogner Shiva, but I'm a bit confused about what to do considering what I discovered. I believe I probed the correct pin to determine the plate voltage (it was ~466VDC), but that seems low considering that Bogners supposedly have high plate voltages. Is this the right pin? I assume so...Anyway, the kicker here is that at the bias trimmer's lowest point, my EL-34's are biased at 50mA! :saeek: According to the Weber Bias calc, I should have them set at 38mA for 70% plate dissipation. What should I do?
Help Biasing a Bogner (Need Pros!)
- Thread starter mrid
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Gearjoneser
Gear Ho
Re: Help Biasing a Bogner (Need Pros!)
What power tubes are you putting in, and what came in it?
I ran into this once with my Ecstasy, by putting the suggested Svetlanas in it, then discovered that the current was pretty high at 49mA. I called Bogner and they said that sometimes a nearby bias resistor needs to be changed if the bias point is out of range. Instead, I tried Tesla JJ's, and luckily they biased up perfectly at 36-37mA.
I'd suggest calling Bogner's customer service, since they're always helpful over the phone.
What power tubes are you putting in, and what came in it?
I ran into this once with my Ecstasy, by putting the suggested Svetlanas in it, then discovered that the current was pretty high at 49mA. I called Bogner and they said that sometimes a nearby bias resistor needs to be changed if the bias point is out of range. Instead, I tried Tesla JJ's, and luckily they biased up perfectly at 36-37mA.
I'd suggest calling Bogner's customer service, since they're always helpful over the phone.
Gearjoneser
Gear Ho
Re: Help Biasing a Bogner (Need Pros!)
By the way, how do you like it so far? Besides the bias issue?
By the way, how do you like it so far? Besides the bias issue?
B
Bones
Guest
Re: Help Biasing a Bogner (Need Pros!)
I bet MrID makes sweet love to it. I know how this fool gets with new gear.
I bet MrID makes sweet love to it. I know how this fool gets with new gear.
7th Hell
New member
Re: Help Biasing a Bogner (Need Pros!)
All questions will be answered here:
http://studentweb.eku.edu/justin_holton/tubes.html#tubefaq
Kind of like setting the idle on a car. You don't want things running either too hot or too cold. This insures optimal tube performance in a tube amp.techonly said:
All questions will be answered here:
http://studentweb.eku.edu/justin_holton/tubes.html#tubefaq
