@johnss with all the discussion on the RIAA curve, would suggest real vinyl philes consider the following; test your LP playback set up and see if the playback response is flat according to the RIAA spec.
theres more to this
Thanks for the write up. Its nice to see this level of interest.
Most digital multimeters fall off starting at a few KHZ and at 20 KHz are down as much s 40dB. Get an old HP AC Voltmeter and check it against an oscillator. The meter should not deviate over the audio range.
Used HP, Tektronix, Heathkit. eico and other test equipment are less than 10 cents on the dollar. An oscillator and meters come first Then you can just watch the music and see how much power you are using, your headroom, noise, lots of things.