Hello!
A fellow friend is interested in building another Dynaco ST-70 after seeing online posts from the forum recently.
He is interested in having another Dynaco ST-70 wire the output tubes in class A triode, do you think Paul Hynes CCS1A / Z100A good for the output stage per channel (2 x EL34)?? Output transformer and power transformer will remain the same for Dynaco ST-70.
He is operating the output tubes at 440v.
CCS1A Constant Current Source
Z100A shunt Voltage Regulator
Thanks!
A fellow friend is interested in building another Dynaco ST-70 after seeing online posts from the forum recently.
He is interested in having another Dynaco ST-70 wire the output tubes in class A triode, do you think Paul Hynes CCS1A / Z100A good for the output stage per channel (2 x EL34)?? Output transformer and power transformer will remain the same for Dynaco ST-70.
He is operating the output tubes at 440v.
CCS1A Constant Current Source
Z100A shunt Voltage Regulator
Thanks!
If you're intending to have a CCS feed a voltage reg, then have that regulated voltage feed the whole amp, this will take a lot of monkeying around to get right.
Your decision to triode wire and stay in class A is good.
You'll have to figure out how much voltage compliance you need across the CCS, then set your voltage regulator accordingly. The CCS is going to have to pass enough current for the amplifier, plus what the regulator needs to keep regulating.
Once you've worked that out, you'll have to decide if the PT can handle what you're asking, as well as whether there's enough regulated voltage available for your output stage.
Thankfully you aren't operating the stage in class AB, as then you have to set the CCS to the maximum current the amp will draw on peaks, plus regulator operating current, then your regulator cooks that heat off at idle and your power transformer cooks itself to death.
Your decision to triode wire and stay in class A is good.
You'll have to figure out how much voltage compliance you need across the CCS, then set your voltage regulator accordingly. The CCS is going to have to pass enough current for the amplifier, plus what the regulator needs to keep regulating.
Once you've worked that out, you'll have to decide if the PT can handle what you're asking, as well as whether there's enough regulated voltage available for your output stage.
Thankfully you aren't operating the stage in class AB, as then you have to set the CCS to the maximum current the amp will draw on peaks, plus regulator operating current, then your regulator cooks that heat off at idle and your power transformer cooks itself to death.
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