Last update01:00:00 PM GMT

Font Size


Menu Style


The Lost Subwoofer Series

  • Prev
  • 1 of 4
  • Next

THE LOST SUBWOOFER SERIES: Whatever happened to JBL's Triple Chamber Bandpass Subwoofer otherwise known as the TCB-4688? 

 I personally installed several of these boxes "back in the day". This sub was an amazing piece of technology. The 4688 was mainly marketed in the Cinema series and didn't really make it into the install or touring market. I plan on writing about "The Lost Subwoofers" more often. Speaker enclosure designs are almost as interesting as the history of flight. Even today many sound guys wake up in the middle of the night with a sub design dancing in their head. I saw an episode of "Myth Busters" that involved blowing the windows out of a car with a servo-driven sub. Back to the 4688.... This was a monster of a sub. 3 chambers with two of JBL's 18" vented gap drivers sandwiched into the center chamber. I took one apart back in the 90's and took pictures and measurements. The 18's are so tightly squeezed into the center chamber it is almost like they built the boxes around the drivers. I have actually removed them for reconing a few times. 


Lower your stage volume

LED Lighting

Change your sanctuary with color

History of Audio

Check out the latest history article

Analog vs. Digital

Embrace the digital age

Go Green »

Green Business
Use green technology

Tech Volunteer Resource Book

The Soundman's Bible

Soundmans-Bible-cover-hpThe Soundman’s Bible is a must have resource guide for every church A/V volunteer.

This guide outlines everything from connector types, microphone placement, mixing techniques,

speaker placement, to safe rigging practices. This is a simple to understand guide that is written for

the church volunteer. Every church sound booth should have this guide available for quick reference.

The Soundman’s Bible is a big book of really great technical information.

Purchase your copy today!

Individually for $19.95

Buy Now


In 10 packs for $149.95

Buy Now