(17-04-2020 14:30)onv писал(а):  Если балансный = парафазный, то картридж станет балансным только, если заземлить ему среднюю точку двух противофазно намотанных секций в каждом канале. А раз такого нет, то он не балансный, а просто взвешенный источник. И подключать его логично к дифференциальному взвешенному входу с большим CMRR.

Полностью согласен, однако в литературе.

Balanced line connected by transformers

The conceptually simplest way to connect to a balanced line is through transformers at each end shown in figure 5. Transformers were the original method of making such connections in telephony, and before the advent of active circuitry were the only way. In the telephony application they are known as repeating coils. Transformers have the additional advantage of completely isolating (or "floating") the line from earth and earth loop currents, which are an undesirable possibility with other methods.