"Michael R. Kesti" wrote in message

Tim Perry wrote:

the online spec sheet claims a THD of .007% @ +4 dB
i wonder if its an actual measurement or is derived in some fashion.

Specifications are never measurments. Instead, specifications are
chosen values of parameters that, when measured, are promised to be
no worse than the values specified. When chosing those values,
manufacturers are walking a line between how good they want their
gear to appear on paper and how many manufacturing rejects and/or
customer returns they are willing to tolerate.

FWIW, totally agreed.