Wrong as drawn
MIGHT work if shorting pot placed across the XLR pins, *after* the 300 ohm resistors R5 and R6 but still the proper way would be to wire it as a non shorting volume control.
Transformer secondary end to end, "ground" and wiper to pins 3 and 2 respectively.
1k pot value is fine there.
MIGHT work if shorting pot placed across the XLR pins, *after* the 300 ohm resistors R5 and R6 but still the proper way would be to wire it as a non shorting volume control.
Transformer secondary end to end, "ground" and wiper to pins 3 and 2 respectively.
1k pot value is fine there.
It is a drawing error. With the pot on the right side of the 300ohm resistors it will work perfectly.
No, its not. Its the complete wrong pot type in this application.
If you wish to adjust a symmetric 600 Ohm line then its necessary to put a symmetric 600 Ohm balanced attenuator into it, which reflects always on in- and output the constant 600 Ohm.
As this method is very oldfashioned and out of style, nowadays we put those kind of pots shown here with different values between the voltage amp tube stages.
Thats good design practise. Or maybe on the input of the circuits. But never on the outputs.
If you wish to adjust a symmetric 600 Ohm line then its necessary to put a symmetric 600 Ohm balanced attenuator into it, which reflects always on in- and output the constant 600 Ohm.
The circuit provides a perfect balance, an acceptably low output impedance and does not overload the amplification stage.
It does not have a constant input impedance but does it really matter?
Sorry but you are wrong.
It stays a balanced output for the very good reason that it´s floating, completely unreferenced to ground, it comes from the secondary of a transformer.
If it drives a true balanced input, either active or best, a transformer, it works as intended.
It stays a balanced output for the very good reason that it´s floating, completely unreferenced to ground, it comes from the secondary of a transformer.
If it drives a true balanced input, either active or best, a transformer, it works as intended.
Its not any longer a balanced output
It is balanced. Only i/p o/p impedance is not constant. Does it matter?
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