|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
69.59.200.72
In Reply to: RE: Distortion tests posted by Doug Schneider on June 21, 2014 at 07:59:13
. . . D.B. Keele used to show the measured HD of EVERY speaker he tested at E-41.2 Hz and A-55 Hz. Occasionally he used B-61.7 or A-440 if he suspected problems in those areas, occasionally graphed THD vs frequency across the whole spectrum, and occasionally showed intermodulation distortion between the low E and A. I don't remember details of his testing regimen, but I do remember some speaker reviews showing up to 40% second harmonic and 53% (!) third harmonic of the low E. No way THAT won't be audible!
Follow Ups:
Funny thing, a VERY high percentage (as in 20-40%) of 2nd harmonic can be inaudible or even pleasant sounding.
Starting with the Abby road album, 2nd and even harmonics were added to 'warm" the sound and guitar amplifiers and even the guitar loudspeakers are set up to have preferably even harmonics.
With natural or machine sounds which are not harmonic in structure (unlike music) , both even and odd harmonics change the timber of sound.
Odd harmonics are dissonant sounding and with both harmonics, it is how far they are from the fundamental which partly governs how audible they will be per masking.
" ... it is how far they are from the fundamental which partly governs how audible they will be ... "
I'd still be interested in the numbers, e.g. how many DB down is the 3rd, 5th harmonic audible, or mess with the sound?
Never trust an Atom, they Make Up everything!
I have explored how low a pure tone I can get out of my system and still have it be relatively undistorted (with no obvious doubling). I do this by experimenting with volume and sine wave pitch and exploring this two dimensional space. At a certain frequency I can adjust the volume to hear a (relatively) undistorted tone with no obvious doubling. By increasing the volume above this point, I begin to hear obvious doubling. At a lower frequency I eventually reach the point where turning up the volume sufficiently to hear anything is already at the point where I hear the doubling. I don't recall exactly where this point was, but as I recall it was around 30Hz with my setup.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: