Resistor between line out and GND: what for?

[chaparK]

Good day,

I was looking at a few output stage schematics and noticed on all a resistor between the line out and the ground, just before the output connector.

This resistor has always a large value, 10K or 100K, and is the last component of the output stage.

What's the purpose of that resistor?

[Ken Newton]

That resistor is there to provide a sure path for current to charge the output coupling capacitor to the operating D.C. bias voltage of the output stage during power up. The reason this resistor is typically large is because it provides a long RC time constant so that the output cap. doesn't charge too fast, and doesn't significantly load down or distort the amplifier output.

[chaparK]

Originally Posted by Ken Newton

That resistor is there to provide a sure path for current to charge the output coupling capacitor to the operating D.C. bias voltage of the output stage during power up. The reason this resistor is typically large is because it provides a long RC time constant so that the output cap. doesn't charge too fast, and doesn't significantly load down or distort the amplifier output.

Good day Ken,

Thanks many times for taking the time to explain and for sharing your knowledge, it makes now perfect sense .

Cheers

Nick