5.6k/2w is for discharge, right?
that should be ok if you add 10000uF larger cap.
Yes for discharge. I may try a pair of 10000uf/63v caps and see if the power supply is happy.
I'm still learning about DIY amps, what is the purpose of doing this (caps between PSU and amp)? How is this wired up?
You just wire the capacitor in parallel with the power supply. From the capacitor you run your wire to the amplifier board dc power input.
The capacitor reduces ripple, works as energy storage, reduces bus pumping…etc
Not sure about its effectiveness at ripple reduction in this application, but it definitely checks off the other two you mentioned.
I've seen amps with capacitors before and after the PSU but not at the same time. Are they serving the same purpose? Before the PSU it's AC and after the PSU it's DC.
So I found that capacitors (in series) before the PSU are DC blockers and capacitors (parallel) after the PSU are "bypass" for unwanted noise? Can they be used in tandem for an amp with SMPS?
Last edited:
I’m not sure what you mean by using capacitors before the power supply? Do you mean the X and Y type capacitors used to filter emi/rfi on the AC line?
Before the PSU meaning AC mains from the wall to capacitors in series to the PSU AC input.
What is it that you are trying to accomplish? Ive only ever used a dc blocker like this to quiet a noisy transformer in a linear power supply.
You may want to give this article a read to get an understanding of how the dc blocker works
https://sound-au.com/articles/xfmr-dc.htm
https://sound-au.com/articles/xfmr-dc.htm
I am not trying to accomplish anything except understand what a builder of a diy amp is trying to accomplish with their build. I'm personally just at wall AC -> smps -> amp board -> speakers. What are the purposes of these extra parts in between? Why might I want to add them for my builds?
Last edited:
DC blockers are for normal transformers, they block dc voltage generated in ac voltage due use of electronic devices on grid power supply.
They are not applicable on switch mode power supply which rectifie ac voltage to dc and after that on high frequency transfer energy to the secondary side of the power supply. So SMPS is the reason why we have on power supply grid dc voltage due high harmonics of the current which flow to the load.
On old style linear transformer dc voltage produce extra loss on primary of the transformer and unnecessary raise magnetisation. Inductance is short for dc voltage. Torodial transformers have more impact on their work with dc voltage on ac grid.
They are not applicable on switch mode power supply which rectifie ac voltage to dc and after that on high frequency transfer energy to the secondary side of the power supply. So SMPS is the reason why we have on power supply grid dc voltage due high harmonics of the current which flow to the load.
On old style linear transformer dc voltage produce extra loss on primary of the transformer and unnecessary raise magnetisation. Inductance is short for dc voltage. Torodial transformers have more impact on their work with dc voltage on ac grid.
Thank you for that explanation. I won't see any real benefit to adding a DC filter with an SMPS. Having a capacitor(s) in parallel with the amp board and an SMPS would probably see some improvement to the amplifier?