JBL S120P II Powered Subwoofer Service Manual

About this manual

This document is a comprehensive service manual for the JBL Studio Series S120P II Powered Subwoofer. It provides detailed technical information including basic and detailed specifications, amplifier block diagrams, electrical parts lists, PCB drawings, and schematic diagrams intended for professional repair technicians.

The guide also includes instructions for various connection methods (Dolby Pro Logic Line Level, Speaker Level, and Digital Surround modes), a test setup procedure, and an exploded view of the unit. It features specific sections on basic troubleshooting, bulletins, and package details.

What's inside

• Basic Specifications
• Detailed Specifications
• Connections
• Operation
• Basic Troubleshooting
• S120PII Amplifier Block Diagram
• S120PII Exploded View
• S120PII Test Setup and Procedure
• S120PII Electrical Parts List
• PCB Drawings

Specifications

Frequently asked questions

What is the DC offset specification?

The DC Offset at speaker outputs must be between 10 mV-DC and 60.

What is the RMS power rating of the JBL S120P II subwoofer?

The amplifier provides an RMS power output of 400 Watts.

What is the driver size and impedance for this subwoofer?

The unit uses a 12-inch PolyPlas driver with a 4.4 ohm DCR.

How can the low-pass crossover frequency be adjusted?

The low-pass frequency is continuously variable from 50Hz to 150Hz.