the load isn't a "topology", it's a description of the job the tube has to do. because the tube you pick has it's own impedance, which varies with signal like a pot, there will be a relationship to the impedance of the load, which hopefully doesn't vary too much (speakers can do that...). the ratio of the two determines how much power winds up in the load. i can't explain that here in any more detail other than to point you to the many resources there are for it. do a search for calculating loadlines... you know the quiescent plate voltage value:440 VDC. and your swing goes from 17 volts positive to 57 plus and minus 23 (80 volts peak to peak). the dissipation is 100 watts continuous... or, you can find something between 3K and 7k and you will wind up with something useful.?! you don't have to be a math bat. just expect to yank and solder a bunch.
hey flathead! no, i wasn't thinking about that amp at all. i was trying to explain A2 and cathode drive as a way to get a bit more out of a higher mu tube than an 845. the reason for doing that in sound practices way back when, was that there were cheap 845s at the time. cheaper than 300Bs. it was a way to make a triode amp butch, and not spend a fortune. the last "dinosaur" is an interesting circuit... especially when taken to the next level: all dc coupled. but that was a long time ago too... i have done some different things since then.
I´m always fascinated by low parts solution and when no interstageformers are included even more.
Have to make a descent box for my OTL before starting anything else.
A 813/C3g Shade projekt has been on the shelf for a long time therefore the interest in dinosaur and the different aspects of driving transmitting tubes.
Have to make a descent box for my OTL before starting anything else.
A 813/C3g Shade projekt has been on the shelf for a long time therefore the interest in dinosaur and the different aspects of driving transmitting tubes.
And as if by magic...
Common-cathode amplifier design ideas
I think I need to do more research..
Regards
M. Gregg
Common-cathode amplifier design ideas
I think I need to do more research..
Regards
M. Gregg
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As I understand some of the benefits of the grounded grid topology:
1. Wider bandwidth due to reduction of miller capacitance.
2. Does not invert phase.
Due to lower input impedance, you will sometime have a cathode follower driving the tube.
Can a differential tube gain stage be considered as grounded grid if the output of non-invert tube 's grid is grounded ?
Also from the same issue of Sound Practice #6: grounded grid input stage mod for AES SE-1 amp. I'm actually using it on my AES SE-1
Here some commercial products that uses Grounded Grid
Transcendent Sound Grounded Grid Preamp
6moons audio reviews: Wyetech Labs Pearl
BTW. M Gregg If you don't already have back copies Sound Practices ... Joe Roberts sometime have entire collection(CD Format) on ebay.
1. Wider bandwidth due to reduction of miller capacitance.
2. Does not invert phase.
Due to lower input impedance, you will sometime have a cathode follower driving the tube.
Can a differential tube gain stage be considered as grounded grid if the output of non-invert tube 's grid is grounded ?
Also from the same issue of Sound Practice #6: grounded grid input stage mod for AES SE-1 amp. I'm actually using it on my AES SE-1
Here some commercial products that uses Grounded Grid
Transcendent Sound Grounded Grid Preamp
6moons audio reviews: Wyetech Labs Pearl
BTW. M Gregg If you don't already have back copies Sound Practices ... Joe Roberts sometime have entire collection(CD Format) on ebay.
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