My upgraded model, has following measured results:

Frequence: Extreemely flat Amplitude over the audible spectrum. Minor drop below 100hz (-0.5dB)

2Hz-38kHz (-3dB)

THD (Input, with Agilent 33120A, Measured with Arta, load 8Ohm):

0.085% @ 1/8W (This is already a loud voice if connected to speaker! just 1st harmonic at less then -80dB)

0.19% @ 1W (2kHz -58dB, all the rest 3,4,5kHz less then -85dB)

0.45% @ 5W -(2kHz 50dB. 3khz -70dB, rest less then -85dB

Setting THD to 1%, measure 9.982W, so

Power: 10W @ 8Ohm (below that is not supported! It will distort)

Signal to noise: Can’t well measure it , somewhere better then 95dB, Phono is 10dB less noisy then playing anything (somewhere -80db…)