[KonstantinT]

peforms both "power step-down" and impedance matching

Hi, I dare to reactivate this thread.

As far as I know, the voltage ratio of primary/secondary side of a transformer is equal with the square root of the impedance ratio.
For example, if a tranformer increases the impedance from 8 to 120 ohms (ratio=15), then on the secondary side the voltage is almost 4 times higher than on the primary.
Can a "standard" headphone driver stand such high voltage?

Second doubt: We don´t want to have resistors in the signal path (between power amp and phones output) because they decrease sound quality. But a tranformer with ist winded wire is automatically a resistor, isn´t it?

Konstantin

 

[Hz_joe]

peforms both "power step-down" and impedance matching Quote:

Hi, I dare to reactivate this thread. As far as I know, the voltage ratio of primary/secondary side of a transformer is equal with the square root of the impedance ratio. For example, if a tranformer increases the impedance from 8 to 120 ohms (ratio=15), then on the secondary side the voltage is almost 4 times higher than on the primary. Can a "standard" headphone driver stand such high voltage? Second doubt: We don´t want to have resistors in the signal path (between power amp and phones output) because they decrease sound quality. But a tranformer with ist winded wire is automatically a resistor, isn´t it? Konstantin

UHC signature is a step down transformers. It step down voltage to safety level for headphone but increase loading resistance seen by amplifiers. Loading impedance of solid state amplifiers is not criticle when resistance is higher than normal loading impedance.