Family Hoof
Well-known member
I'm worried about noise in mic preamp power supply that gets the +24V and +48V phantom from the same 24VAC transformer secondary. I would've liked to use a dual secondary (48VAC center tapped) transformer for isolation between the two supplies but could not find one that fits in a 1RU chassis. The 48V comes from a doubler which taps the AC before it gets to the full wave rectifier for the 24V supply. I'll try to post the schematic in The Lab when I have a legible copy drawn.
Is extra noise really something to worry about? Should I use an external supply with the center tapped trafo instead?
Also, as the subject of this post says, feel free to discuss other ways to reduce audible noise and hum in a linear DC power supply. I know about using IEC inlets with EMI shielding and that it's good to filter out any DC offset before the trafo primary. Any other fun tips?
Thanks!
Is extra noise really something to worry about? Should I use an external supply with the center tapped trafo instead?
Also, as the subject of this post says, feel free to discuss other ways to reduce audible noise and hum in a linear DC power supply. I know about using IEC inlets with EMI shielding and that it's good to filter out any DC offset before the trafo primary. Any other fun tips?
Thanks!