JBL 136A Woofer
1973-1975
The 136A was a massive 15" professional-grade woofer with an Alnico V magnet, designed for the most demanding applications. It served as the foundation of the legendary L200 Studio Master system, delivering effortless bass and exceptional dynamics.
Specifications
| Nominal Diameter | 15" (38cm) |
|---|---|
| Magnet Type | Alnico V |
| Voice Coil | 4" (100mm) edgewound aluminum |
| Cone Material | Reinforced paper |
| Impedance | 8 Ω / 16 Ω versions |
| Power Handling | 100W continuous |
| Frequency Response | 35 Hz - 800 Hz |
| Sensitivity | 94 dB/W/m |
| Weight | 12 kg |
Key Features
- Massive Alnico V Magnet: Large Alnico magnet structure for high flux density
- 4" Voice Coil: Oversized voice coil for exceptional power handling
- High Sensitivity: 94 dB efficiency for dynamic, uncompressed sound
- Professional Grade: Built to studio monitor standards
Applications
- L200 Studio Master (1973-1975)
- Professional studio monitors
- Cinema sound systems
Historical Context
The 136A was derived from JBL's professional cinema and studio monitor drivers. Its exceptional sensitivity and low distortion made it ideal for the L200, which was essentially a domesticated version of JBL's professional monitoring systems.
The 15" diameter provided moving area equivalent to multiple smaller woofers, allowing effortless reproduction of bass frequencies at realistic levels. This "effortless" quality - the sense that the speaker isn't straining even at high volumes - became a hallmark of JBL's large-format systems.
Documentation
- JBL Loudspeaker Components 1979 Catalog - Contains 136A specifications
- JBL Thiele-Small Parameter Manual (PDF) - Technical reference for woofer parameters