Total harmonic distortion (English Wikipedia)

Introduction to the Basic Six Audio Tests: "Since the sum of the distortion products will always be less than the total signal, the THD+N ratio will always be a negative decibel value, or a percent value less than 100%."
"Raising the Bar for Rub & Buzz Defect Detection". Audio Precision. Retrieved 2024-12-12. High-Order Harmonic Distortion (HOHD…) – A classic method for rub & buzz detection, HOHD uses the THD (Total Harmonic Distortion) ratio but only of harmonics above the 10th, 10-35, 20-200, etc., which is a simple way to account for frequency masking effects. … Rub & Buzz Loudness … Applies a psycho-acoustic loudness model to the residual signal to calculate the perceived level of the rub and buzz

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"39/41B Power Meter Glossary" (PDF). %THD-F … ratio of the harmonic components … to the voltage … of the fundamental alone. … %THD-R … ratio of the harmonic components … to the total voltage … including the fundamental and all harmonics.

Skvarenina, Timothy L. (2018-10-03). The Power Electronics Handbook. CRC Press. ISBN 978-1-4200-3706-7. In the opinion of some, [THD_F] exaggerates the harmonic problem. … [THD_R] is used by the Canadian Standards Association and the IEC.
Gross, Charles A. (October 20, 2006). Electric Machines. CRC Press. ISBN 9780849385810 – via Google Books.

Nachbaur, Fred. "THD Measurement and Conversion". Fred's Vacuum. Retrieved 2024-06-05. This number indicates the RMS voltage equivalent of total harmonic distortion power, as a percentage of the total output RMS voltage.

Blagouchine, Iaroslav V.; Moreau, Eric (September 2011). "Analytic Method for the Computation of the Total Harmonic Distortion by the Cauchy Method of Residues". IEEE Transactions on Communications. 59 (9): 2478–2491. doi:10.1109/TCOMM.2011.061511.100749.
"IEEE Standard for Harmonic Control in Electric Power Systems". IEEE STD 519-2022 (Revision of IEEE STD 519-2014): 1–31. 2022. doi:10.1109/IEEESTD.2022.9848440. ISBN 978-1-5044-8727-6.
"On the definition of total harmonic distortion and its effect on measurement interpretation". IEEE Transactions on Power Delivery. 20 (1): 526–528. January 2005. doi:10.1109/TPWRD.2004.839744. It has been shown that THD_F is a much better measure of harmonics content. Employment of THD_R in measurements may yield high errors in significant quantities such as power factor and distortion factor
Baptista, José MR; Cordeiro, Manuel R.; Machado e Moura, A. (2003). "Voltage Wave Quality in Low Voltage Power Systems" (PDF). Renewable Energy and Power Quality Journal. 1 (1): 117–122. doi:10.24084/repqj01.317. Two equations exist to calculate the THD…
Faventi, R.; Hopper, H.; Torrente Rodriguez, M. (2014). "Low power transmission plastic gear trains: Which parameters affect the subjective acoustic quality?". International Gear Conference 2014: 26th–28th August 2014, Lyon. pp. 208–218. doi:10.1533/9781782421955.208. ISBN 978-1-78242-194-8.

Baptista, José MR; Cordeiro, Manuel R.; Machado e Moura, A. (2003). "Voltage Wave Quality in Low Voltage Power Systems" (PDF). Renewable Energy and Power Quality Journal. 1 (1): 117–122. doi:10.24084/repqj01.317. Two equations exist to calculate the THD…

"RTA Window". www.roomeqwizard.com. Retrieved 2024-12-12. HHD (higher harmonic distortion for harmonics from the 10th up to at most the 50th)

Section 11: Power Quality Considerations. Bill Brown, P.E., Square D Engineering Services.

Elliott, Rod (2009). "Valves vs. Transistors (Part 1)". Elliott Sound Products. Retrieved 2024-12-12. [Crossover distortion] may barely register on a distortion meter, so the figures looked excellent. Unfortunately … listeners could hear the distortion - it was plainly audible, and sounded dreadful.

IEEE 519 and other standards (draft): "distortion factor: The ratio of the root-mean-square of the harmonic content to the root-mean-square value of the fundamental quantity, often expressed as a percent of the fundamental. Also referred to as total harmonic distortion."
"Total Harmonic Distortion of a square wave". September 11, 2012. Archived from the original on 2012-09-11.

AEMC 605 User Manual. "THDf: Total harmonic distortion with respect to the fundamental. THDr: Total harmonic distortion with respect to the true RMS value of the signal."