lewm
I think you switched things inadvertently, the 30 ohm input is 18.27 xf, I prefer the 10 ohm setting which is 20.68 xf
actual #s from FRT-4 specs:
3 ohm input: xf 35.84; gain 31db, .3mv = 10.8mv, impedance load 37 ohms
10 ohm input: xf 20.68; gain 26db; .3mv = 6.3mv, impedance load 110 ohms
30 ohm input: xf 18.27; gain 25db; .3mv = 5.4mv, impedance load 141 ohms
100 ohm input: xf 10.55; gain 20db; .3mv = 3.3mv, impedance load 423 ohms
I think you switched things inadvertently, the 30 ohm input is 18.27 xf, I prefer the 10 ohm setting which is 20.68 xf
actual #s from FRT-4 specs:
3 ohm input: xf 35.84; gain 31db, .3mv = 10.8mv, impedance load 37 ohms
10 ohm input: xf 20.68; gain 26db; .3mv = 6.3mv, impedance load 110 ohms
30 ohm input: xf 18.27; gain 25db; .3mv = 5.4mv, impedance load 141 ohms
100 ohm input: xf 10.55; gain 20db; .3mv = 3.3mv, impedance load 423 ohms