I intend to run a SE amp and a PP amp in the same chassis using a Fender Dual Showman power transformer.
Is it worth installing a diode in each power supply filter string as they branch from the reservoir ( both amps will be in use together)
SE and PP amp circuits sharing reservoir capacitance
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Malcolm Irving
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Re: SE and PP amp circuits sharing reservoir capacitance
I don't think there is a need for a diode. Reservoir needs to be big enough for both amps (add the uF usually used for the SE to that for the PP). If you are thinking of tube rectification - watch out not to exceed the maximum capacitive load of the rectifier tube.
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Stevem
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Re: SE and PP amp circuits sharing reservoir capacitance
With both output sections share the same Ot?
How are you planing to drain the power supply down when to switch to SE mode?
In PP mode your plate voltage will be about 430 volts and in SE your going to drain out atleast 100 volts by my figuring!
Recto tube wise a 5U4 is good for 40 UF and 5AR4 is good for 60 UF of filtering.
How are you planing to drain the power supply down when to switch to SE mode?
In PP mode your plate voltage will be about 430 volts and in SE your going to drain out atleast 100 volts by my figuring!
Recto tube wise a 5U4 is good for 40 UF and 5AR4 is good for 60 UF of filtering.
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Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: SE and PP amp circuits sharing reservoir capacitance
I'll be using separate output transformers and output jacks, bleeder resistors in each filter chain.
I'd heard that using a diode may help in less interaction when both chains are in use...
The plan is to utilise the tone of the overdriven PP section feeding into my Palmer PDI-03 then into the SE amp feeding the speaker.
I'd heard that using a diode may help in less interaction when both chains are in use...
The plan is to utilise the tone of the overdriven PP section feeding into my Palmer PDI-03 then into the SE amp feeding the speaker.
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Stevem
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Re: SE and PP amp circuits sharing reservoir capacitance
If the total number of gain stages for each section is different then one of your speaker jacks can not be grounded to the chassis it will need to float.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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martin manning
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Re: SE and PP amp circuits sharing reservoir capacitance
Might get around that some way, but good point.
Re: SE and PP amp circuits sharing reservoir capacitance
The signals should be in phase - all jacks are isolated from the chassis to which the circuit is grounded at one input.