Harmonic distortion of audio frequency from Rigol DG1022Z

[@Kazik70]

TDS5000 old and beautiful :)

[@ruhnet]

Looks like the Rigol is doing an excellent job! 👍 Yes it's OK (and good) to use averaging. For a good primer on optimal FFT settings for best accuracy, check out W2AEW's video #65: kzbin.info/www/bejne/pYPJXnymfJuLd9k But I would think that if you are seeing the primary peak at the proper (known) level that the smaller peaks should be mostly accurate. Looks like your 3rd, 4th, 5th, and 6th are the highest harmonics at -58, -56, -54, and -60dBc, so added together those would be around -50dBc, which is about 0.316% THD, which is very good. (I wouldn't take into consideration the second harmonic or any other peaks below -60dBc as their influence is so tiny.)