Rare Vintage Find : "Norman Laboratories electronic crossover - amplifier System 12"


Just had two of these gifted to me.  Can find VERY little info.  Check 'em out.
FRONT IMG-0315 — ImgBB (ibb.co)
REAR IMG-0316 — ImgBB (ibb.co)

  • The company was in Norman OK, and is know for speakers, many say they are fine.
  • Heck, I'm not even completely sure what are or do.
  • I think these came as part of a speaker system.  Would each one be good for a L/R pair or just one side?
  • Wondering if they can be used as a crosser for a two-way speakers and a passive subwoofer?
  • I think they came from a university surplus, either electronics or music department.

Mainly I just wanted to show them off given their rarity.  I cannot find any other pictures of the crossover/amp, and only one of the speakers.  The speakers looked crazy unique & cool. See Link for five pictures:  NORMAN LABS 12-B SPEAKERS Photo #453801 - Canuck Audio Mart

Would appreciate any info folks may have.  I'm thinking the best use might be to reunite them with someone who has the speakers but no crossovers.

Enjoy and discuss among yourselves.
gemoody

Showing 1 response by imhififan

This is my guess:

The two RCA "input" connect to a preamp L and R output.
The RCA jacks marked "amp" output low-pass signal (32, 100 or 200Hz)  to two external power amp channels to drive L and R woofer.
The two external power amp channels outputs connect to "right amp" and "left amp" spring connectors via speaker cables.
The left and right tweeter will powered by the internal amp.

Wonder what do the 4 "calibrate" buttons and knobs do?
I guess it is to set the gain of internal power amp to match the external "woofer" amps.