Seen a couple of mods grounding the grid, which I understand the pp/se mod does, replacing the grid leak with a fixed resistor and a pot. Is there an effective difference between this and running a single el84 SE amp?
Also seen a ppimv for just 2 out of 4 tubes (one of each push pull pair) for 36 watt. Again, what is the effective or theoretical difference between an 18watt and a 36 watt with two tubes with two tubes' grid connected to ground? Any experience/ explanations / drawbacks appreciated thanks.
Power switches/ se mods
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chaliapin
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Re: Power switches/ se mods
Any experience of either of these mods?
Looked at the half power switch for 36-18 watt switching the cathode, but isn't grounding the grid easier? Don't have to worry about the cathode bias etc. What's the drawback, am I missing something?
Looked at the half power switch for 36-18 watt switching the cathode, but isn't grounding the grid easier? Don't have to worry about the cathode bias etc. What's the drawback, am I missing something?
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Daviedawg
- Superior Amp Tech
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Re: Power switches/ se mods
The TH30 switches the cathodes of one of each pair of EL84 out of circuit. I repaired and ran one for a year or so.
Dd
Edit. Sorry not quite that simple. See schematic.
Dd
Edit. Sorry not quite that simple. See schematic.
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