Compression drivers had to "pull" on the voice coil. I can easily see a small engineering group establishing a standard that positive going current pulls in all drivers, woofers or horn drivers. JBL chose to go all coils the same, Altec chose to have woofers different from their compression drivers. Ain't it that simple, after all?
I still hold that since I can't be sure that every one of my vinyl and digital disks, and each and every cut on same, are outputting absolute polarity, then I can't also pretend it makes a difference if my woofers Woof or Moof.
David F
San Jose
... or foow/foom, ... fwiw.
Speaker Guy:
The only twist on all that is that JBL knew the RED post was negative, so when they used their drivers in their own enclosures they wired them accordingly so that a positive charge moved the speakers forward. I like the first story I heard about this, in that it was simply a mistake in initial production. They had shipped large quantities in the beginning before they even realized they were wired backwards, then decided to keep it that way so that the next batch would be in sync with the previous ones.
Except, the positive signal from an amp went to the Red terminal on the x-over, and the black terminal of the Crossover went to the black of all the drivers. So, after exiting the network, the positive signal out of the x-over went to the speakers Red terminal, which resulted in the speakers moving backward, into the gap. At least, that's how I remember it on the N500, N1200, N2500, etc..
Again, this is as I recall, from 40+ years ago.
Speaker Guy;
I'm not sure why this is so interesting to me... but it is. The old 4560 and those Scoop bass bins from the seventies (they had the single and duel 15 design) were wired so that positive (tip) of the phone plug advanced the speakers forward. Also a 12dB per octave passive crossover network flops the phase 180 degrees. The more recent SR4715 with two 2226H, which I own 4 of, also move forward with positive.
I still think they just made a mistake in the beginning??? I have worked with Altec, Utah, Jensen, Peavey, McCaulley, Eminence, Celestion, Yamaha, Carvin, EV, Community, Cerwin Vega, Oxford, Rola, Community, Grundig, Olson, Weber, Cleveland, Heppner, and several more. JBL is the only speaker I've seen with RED negative.
PS Don't get me wrong... out of all of those... JBL drivers are my favorites. I also really miss the D, K, & E series. I understand the alnico shortage, but liked the "E" series too. JBL should really bring them back!
I just got my Cricket yesterday for Phase checking. What a great unit!!
http://www.musiciansfriend.com/produ...5&src=3SOSWXXA
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