I am planning to build and LCLC PSU filter for a tube PSE amplifier, and I am debated on 'how good' capacitors I should use in each position to achieve the best sonic performance.
My though process:
C2 is connected directly to the anodes, so the current across it is characterized by large/steep swings and the same frequency of the audio signal, hence I want a high performance capacitor in that position: most likely a high grade electrolytic capacitor in parallel to a film one.
On the other end, C1 current swing frequency is limited by L1/L2, hence my deduction is that any decent capacitor should be good in that position.
Any opinions?
My though process:
C2 is connected directly to the anodes, so the current across it is characterized by large/steep swings and the same frequency of the audio signal, hence I want a high performance capacitor in that position: most likely a high grade electrolytic capacitor in parallel to a film one.
On the other end, C1 current swing frequency is limited by L1/L2, hence my deduction is that any decent capacitor should be good in that position.
Any opinions?
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On this matter alone, consider the need to filter higher frequencies. This applies also to L1.
This may sound dubious to you but I can only say different brand/types of same value will have different sound.
You can only find out by trying as this correlates with the circuit that your powering.
You can only find out by trying as this correlates with the circuit that your powering.
From my insatiable urge to muck around all caps will have influence, ironically sometimes cheap caps can sound better can't explain why. What I can recommend hands down is to use a 0.1 to 0.47 uf Mundorf Supreme cap as the first C so it becomes a clclc instead. Why cause the sound of this cap is very very good & it's not expensive given its small value. You can give it a try after you build your Lclc supply.
Besides the small value will not upset the design of your psu.
Besides the small value will not upset the design of your psu.
The impedance of electrolytics is very low compared to valve circuitry impedances, I'd worry about lifetime at temperature, not performance.
@Mark Tillotson
Have you ever had a chance to measure the impedance of any electrolytic cap at 20Khz ?
Have you ever had a chance to measure the impedance of any electrolytic cap at 20Khz ?
36 milliohms reactive for a 220uF cap, ESR on top of that, compared to kohms or 10's of kohms for the valve circuit... probably 80dB difference not including the amp's PSRR.