PDA

View Full Version : 127a and 127h



midlife
11-07-2009, 08:20 PM
Are the 127a and 127h drivers specs close enough to allow these speakers to be substitued for one another? thanks

Fred Sanford
11-08-2009, 04:26 AM
Are the 127a and 127h drivers specs close enough to allow these speakers to be substitued for one another? thanks

I believe they are, but not the "H-1"...they don't even physically fit in many applications, because the 127A + Hs were often installed sunken into the baffle.

I'll link you to actualy specs if I find them, I did do this research a few months ago...

je

doyall
11-08-2009, 09:02 AM
From http://www.jblproservice.com/pdf/Thiele%20Small%20Parameters/Theile%20Parameters.pdf

MODEL FS QTS QMS QES VAS EFF PE XMAX RE LE SD BI MMS FLUX

127A 25 0.43 7.5 0.46 235.1 0.77 50 4.83 5.2 0.7 0.049 7.5 32 0.85
127H 25 0.43 7.5 46 237.9 0.77 50 4.83 6.6 0.7 0.032 7.5 33 1.07

Except for 2 or 3 items the TS parameters are very close. Whether the items on which they are different are consequential, I have no idea.

BJL
11-09-2009, 09:15 AM
L40 & L40A both used same N40 network.
L50 & L50A both N50