JBL Century L100a woofers

[Inspector34]

Looking for replacement woofers for my JBL Century L100a speakers, will the 128H woofers from the L112 be a suitable replacement?
Thank you so much for your time..

[Anthony L100]

Hi Inspector, and welcome! Although the 128H would physically fit, the L100As run the 123A woofer full range as it has a smooth rolloff. The 128H needs to be crossed over in the 1000Hz region so wouldn't really be suitable without crossover mods. Also, you would lose that "voicing" that makes the L100 what it is:D. Why not try and source a pair of 123A-3s, they seem to come up regularly on e-bay and have your L100As sound just like they should.

[boputnam]

Why not try and source a pair of 123A-3s, they seem to come up regularly on e-bay and have your L100As sound just like they should.Not exactly...

The 123A-3 is a negative transducer. The 123A-1 is an unusual (for JBL) positive transducer (cone out on + voltage).

If you swap in the 123A-3. you need to cross wire it (RED to Black, BLK to Red) to maintain the cabinet phasing JBL intended. Then, "your L100As sound just like they should." :applaud:

[Anthony L100]

Not exactly...

The 123A-3 is a negative transducer. The 123A-1 is an unusual (for JBL) positive transducer (cone out on + voltage).

If you swap in the 123A-3. you need to cross wire it (RED to Black, BLK to Red) to maintain the cabinet phasing JBL intended. Then, "your L100As sound just like they should." :applaud:

Yes Bo, good point, having had a look through the tech manuals I now see L100As used the 123A-1 in the earlier models, and 123A-3 in the late version.

[boputnam]

Yea, and if you mean the Tech Sheets, you'll see that the 2213H, found in the 4312 series can be directly swapped-in for the 123A-3 (wire "by color"), and for the 123A-1 (by cross-wire). Works fine.