JLM AUDIO

I'm adding a JLM Go-Between to my DIY pre amp. I'm using this transformer to power the power supply. It's a 15VA 0-25 0-25 toroid which gives me 50Vac when wired in series. 50 / 15 = 100mA, which I think is well within spec for phantom power.

Without the Go-Between hooked up to the power supply, power supply outputs 50Vdc. When I plug in the Go-Between the voltage at the output of the power supply drops to 32Vdc. When I plug a condenser mic into the pre amp the voltage drops further to 22Vdc.

Do you know what could be causing this?

Thank you.

What power supply are you using to convert the transformer ac to a regulated dc power supply?

Hi Joe,

Thanks for your reply but I have just this second solved the issue! It turns out I had wired the power transformer incorrectly.

I'm using a power supply PCB that 'ruffrecords' produces over on the Group DIY forum.

Thanks,

Matt