On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47*pm, Larry Jaques wrote:
On Thu, 02 Dec 2010 14:10:40 -0500, Bill
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, *wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). *The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.

Total harmonic distortion in fluors? *New one on me.

Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.

So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?


Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.

What _I_ want to know is if the phases are linear in my light
fixtures. Dat's impotent!


'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)

I think I prefer a 60 cycle hum to Dijon.

--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams