Hi,
I have at home 2x 220µF/63 V Capacitors which I want to use fpr the splitted cathode (2x 100 Ohm) of the 4 EL84.
Is this enough, or is it a must have to bring there 100V capacitors.
How high is the voltage swing there?
Best
Hans-Jörg
Max voltage of the Rocket power amp cathode bypass capacitor
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Re: Max voltage of the Rocket power amp cathode bypass capacitor
the voltage for the bypass caps is plenty. I don't know what you are running in your amp. but just guessing, a 100ohm resistor for a pair would be a bit hot. just depends on what voltages you have.
I would probably look more at 125 to 130ohm for a cathode resistor for a pair of EL84s. If you have fairly higher voltages, i'd use a 150ohm resistor for the pair.
Some amps do run 100ohm for a pair of EL84s, but thats going to proably have them running pretty hot. You might find the amp may sound good, if you get tubes that can handle that. But if you use the 120 or higher, then you will probably be able to use a more varity of brands of tubes.
I would probably look more at 125 to 130ohm for a cathode resistor for a pair of EL84s. If you have fairly higher voltages, i'd use a 150ohm resistor for the pair.
Some amps do run 100ohm for a pair of EL84s, but thats going to proably have them running pretty hot. You might find the amp may sound good, if you get tubes that can handle that. But if you use the 120 or higher, then you will probably be able to use a more varity of brands of tubes.
Re: Max voltage of the Rocket power amp cathode bypass capacitor
Hi,
I understand. I (will) have there around 300-320VDC with a 275VAC secundary into the GZ34 (should hit 310-315V).
I mentioned the 100 Ohm per pair becaus the schem shows 50 Ohm for 4 EL84.
But you might be right to raise them a bit (like my 18 Watt Marshall clone - 130 Ohm there).
But I can use the 2 x 220µF. How high gets the Voltage there.
The problem is very simple: I have 2x63V Cs axial they fit like a shoe.
And I have 2 x 100V but radial. So they will probably touch the bottom plate.
So what to do? Technikal are there some possibilitys but would be 63V enough with around 300V on the plates (almost Rocket values)?
Thank you
Hans-Jörg
I understand. I (will) have there around 300-320VDC with a 275VAC secundary into the GZ34 (should hit 310-315V).
I mentioned the 100 Ohm per pair becaus the schem shows 50 Ohm for 4 EL84.
But you might be right to raise them a bit (like my 18 Watt Marshall clone - 130 Ohm there).
But I can use the 2 x 220µF. How high gets the Voltage there.
The problem is very simple: I have 2x63V Cs axial they fit like a shoe.
And I have 2 x 100V but radial. So they will probably touch the bottom plate.
So what to do? Technikal are there some possibilitys but would be 63V enough with around 300V on the plates (almost Rocket values)?
Thank you
Hans-Jörg
Last edited by hans-jörg on Wed Nov 28, 2012 11:50 am, edited 1 time in total.
Re: Max voltage of the Rocket power amp cathode bypass capacitor
63V is more than enough.
For a pair of EL84s you won't even reach 20V.
For a pair of EL84s you won't even reach 20V.
Re: Max voltage of the Rocket power amp cathode bypass capacitor
Thank you.
I never read more (with my volt meter) than 20V at speaker lug. But didn´t try with all way up and hard strokes. So there could be a lot more than 20VAC.
I had once a small shaping capacitor (100V) in an Attenuator which expoloded on full range ... (There was a Dumble clone in the entry)
But this could also been a classical "Monday cap". The second one is still in and alive (100V too).
Best
Hans-Jörg
I never read more (with my volt meter) than 20V at speaker lug. But didn´t try with all way up and hard strokes. So there could be a lot more than 20VAC.
I had once a small shaping capacitor (100V) in an Attenuator which expoloded on full range ... (There was a Dumble clone in the entry)
But this could also been a classical "Monday cap". The second one is still in and alive (100V too).
Best
Hans-Jörg