I want to create an isolation, impedance matching, balancing transformer for a DI box. I want it to work on Audio frequency and use a toroidal ferrite core.
The input is an electric guitar, so it needs 1M Ohm input impedance. The output is a line-in so it needs about 2k Ohm impedance.
I attempted to calculate the required turns using this, but I am baffled as it seems that only the ratio matters.
If it indeed is so, how many turns should I use? What determines the frequency range of the transformer?
If I am wrong(probably I am), then please explain how exactly.