03-05-2016, 11:15 PM
For 20,90 pushpull, 77 to 111 with 45 pushpull 125CT series is optimal. Though many xfmrs will work, they won't work correctly. The voice coil of these speakers is around 0.7 ohms and it needs to be converted with 1:10,000 ratio to present the needed impedance. 125C has many various ratios. Most other xfmrs are created for 8 ohm coils.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.