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Thanks pdf64 and Merlin.
Ver 12 f attached. I'm pondering whether the dwell control could be 250k or 1M? (I suppose 1M is better). If need be, I can put a grid stopper on the 2nd 1/2 grid pin later.
In driving the first 1/2 of the 12AT7 from the buffer stage (as I have shown now), is a grid stopper really necessary? (I have shown one in any event). I guess the voltage swing off the CF cathode is large enough to put surplus charge the 0.1uF coupling cap, and if there is a 1M grid leak at the 12AT7 first 1/2, then you might get problems, but does the low impedance output of the CF stage mitigate that somewhat (or is it irrelevant?). Besides that, there is a 100k cathode resistor right there which may help bleed excess charge to ground (methinks?) - in addition to allowing a signal to be taken off the cathode.
I'll leave the 2nd 1/2 of the 12AT7 bypass to later experiment.
I've also shown 100k on the recovery stage grid (but obviously 47k will provide sufficient impedance bridging as well for minimal noise). I note that the 6G15 has a whopping 250uF bypass cap, but I wonder why? I thought it might be fun to see if increasing it to that ballpark makes any difference.
I'll leave the recovery stage tone stack issues until I get the reverb intensity sorted. (at the moment there's good treble response but not good bass response - and I'm hoping this will balance out more if I can get more drive into the pan)
Lastly, I guess its still okay, with this revised topology, to power the 1st 1/2 of the 12AT7 from the same supply node as the V1 plates?
I appreciate your support. Cheers :-)
Ver 12 f attached. I'm pondering whether the dwell control could be 250k or 1M? (I suppose 1M is better). If need be, I can put a grid stopper on the 2nd 1/2 grid pin later.
In driving the first 1/2 of the 12AT7 from the buffer stage (as I have shown now), is a grid stopper really necessary? (I have shown one in any event). I guess the voltage swing off the CF cathode is large enough to put surplus charge the 0.1uF coupling cap, and if there is a 1M grid leak at the 12AT7 first 1/2, then you might get problems, but does the low impedance output of the CF stage mitigate that somewhat (or is it irrelevant?). Besides that, there is a 100k cathode resistor right there which may help bleed excess charge to ground (methinks?) - in addition to allowing a signal to be taken off the cathode.
I'll leave the 2nd 1/2 of the 12AT7 bypass to later experiment.
I've also shown 100k on the recovery stage grid (but obviously 47k will provide sufficient impedance bridging as well for minimal noise). I note that the 6G15 has a whopping 250uF bypass cap, but I wonder why? I thought it might be fun to see if increasing it to that ballpark makes any difference.
I'll leave the recovery stage tone stack issues until I get the reverb intensity sorted. (at the moment there's good treble response but not good bass response - and I'm hoping this will balance out more if I can get more drive into the pan)
Lastly, I guess its still okay, with this revised topology, to power the 1st 1/2 of the 12AT7 from the same supply node as the V1 plates?
I appreciate your support. Cheers :-)
), so I am over the moon about it. Thanks once again to everybody here for your helpful suggestions and participation.
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