Measurement taken off single ended output.
Jumper off (high gain)
Switch 1 ON (50 ohm input impedance)
fc 1kHz
Vin 0.328 mVrms
Vout 1.0 Vrms
Gain 69.7 dB
THD < 0.0002 percent mostly second harmonic
Hello,
I have built and measured multiple iterations of the Pearl 3 Vinyl Pre-Amplifier.
The Capacitance multiplier, cascode, JFETS and feedback loops that include discrete transistors are all fun to dissect and wrap your head around.
The Pearl-3 has two levels of gain; high and very high. Reducing the gain by adjusting the resistor values in the feedback loop has the high cost of increasing distortion.
If you use the jumper to select the P-3 low gain of 50 db's and use a mc cartridge this setting will allow overhead for vinyl clicks and pops.
It was pointed out that the level of gain depends on your system.
The common system gain is summed across a Vinyl Pre-Amplifier, a pre-amplifier and a power-amplifier. The final output is controlled by at least one Volume Pot some where in the chain.
A issue that I see is that most of the gain is in the pre-pre-amplifier not leaving any headroom for clicks and pops on the vinyl. The pre-amp even if it has only a few dB's of gain is still too much and needs a lot of attenuation to avoid overdriving the power-amp.
My vinyl collection is mostly well used over the years and or purchased used. My TT is a DJ workhorse and the cartridge is a mid range mm.