there is a difference as to whether you go to cathode or to ground with the divider and or bypass cap...
you can mix that up to taste as well.
6SJ7 Pentode Operating Conditions
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Re: 6SJ7 Pentode Operating Conditions
lazymaryamps
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Re: 6SJ7 Pentode Operating Conditions
During your experiments did you used a common pot or a 2-3W pot ?
Franco
Franco
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Re: 6SJ7 Pentode Operating Conditions
I used a common pot. I believe I double checked the current on the screens of most sharp cut off pentodes was less than .75 w... ... And with a divider the screens dont run into the same conditions as they would dangling at the end of a series resistance.
lazymaryamps
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Re: 6SJ7 Pentode Operating Conditions
Thanks
Franco
Franco
Re: 6SJ7 Pentode Operating Conditions
Is the pot noisy when rotated?
Is this arrangement suitable for mounting on the front (or back) panel?
How would you characterize the tonal difference of connecting the screen cap to ground vs. to cathode?
Is this arrangement suitable for mounting on the front (or back) panel?
How would you characterize the tonal difference of connecting the screen cap to ground vs. to cathode?
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Re: 6SJ7 Pentode Operating Conditions
I've rigged it inside on a PCB. I didn't want it as a tone control.
I wanted a flexible rig to run a variety of pentode types.
Could be useful as a tweak but once you find the devices optimal
operating point all your doing is emphasizing the less than
optimal tone ... I know theres a lot room here... And finding "The" tone
Doesnt mean perfection. Worth a try
I wanted a flexible rig to run a variety of pentode types.
Could be useful as a tweak but once you find the devices optimal
operating point all your doing is emphasizing the less than
optimal tone ... I know theres a lot room here... And finding "The" tone
Doesnt mean perfection. Worth a try
lazymaryamps
- Kagliostro
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- Location: Italy
Re: 6SJ7 Pentode Operating Conditions
I'm wondering if such a pot will be interesting (I think it can be) in an arrangement similar to the schematic I've posted previously
http://ampgarage.com/forum/viewtopic.ph ... 30#p370157
I think the regulation of the gain can be very interesting as there are two different condition of work of the pentode there
Franco
http://ampgarage.com/forum/viewtopic.ph ... 30#p370157
I think the regulation of the gain can be very interesting as there are two different condition of work of the pentode there
Franco