Vintage Speaker Maintenance - QLS-1 Woofer Recap and Base Repair
Capacitors are like small batteries, they hold an amount of charge in the dielectric material they are made of. Much like a battery, they are not forever and electrolytic capacitors in particular dry up over time requiring replacement. There are a plethora of other types of capacitors, such as film that don’t need replacing unless they test poorly. The QLS has both types in its crossover, film caps separating the upper frequency and the large “can” electrolytic capacitors make up the circuit for the woofer. The film capacitors still test fine so I chose to leave them alone for now, as I had enough to work on. The crossovers in the QLS are located in the lowermost cavity of the speaker, in the bases. Taking the woofers out will expose the bolts holding the two parts of the tower together. I unhooked and marked all of the leads going from the circuit up to the drivers and proceeded to separate the cabinet. After removing the bolts and laying the speaker on its side, a quick knock wi...