Since i have no idea what's the output impedance of my preamp i want to measure it.
I tried potentiometer method.
Line input, level scale set to 0dB.
I replaced 100k termination resistor with 100k potentiometer, generator (600Ω output) 2.2Vpp
Output:
Without termination and with 100k - 1.9Vpp
Drop to 0.9Vpp with potentiometer set to 5Ω
With 1k termination - 1.9Vpp
Drop to 0.9Vpp with potentiometer set to 15Ω
Changed input level to 1Vpp
Output:
Without termination and with 100k - 0.8Vpp
Drop to 0.4Vpp with potentiometer set to 2.88Ω
With 1k termination - 0.8Vpp
Drop to 0.4Vpp with potentiometer set to 23Ω
Right now what i measured gives me 15-23Ω impedance range.
Is this method gives proper results?
How i should properly measure it?
Should i measure it with 100k terminating resistor and additional potentiometer load?
I tried potentiometer method.
Line input, level scale set to 0dB.
I replaced 100k termination resistor with 100k potentiometer, generator (600Ω output) 2.2Vpp
Output:
Without termination and with 100k - 1.9Vpp
Drop to 0.9Vpp with potentiometer set to 5Ω
With 1k termination - 1.9Vpp
Drop to 0.9Vpp with potentiometer set to 15Ω
Changed input level to 1Vpp
Output:
Without termination and with 100k - 0.8Vpp
Drop to 0.4Vpp with potentiometer set to 2.88Ω
With 1k termination - 0.8Vpp
Drop to 0.4Vpp with potentiometer set to 23Ω
Right now what i measured gives me 15-23Ω impedance range.
Is this method gives proper results?
How i should properly measure it?
Should i measure it with 100k terminating resistor and additional potentiometer load?