Schematic — Jbl N7000

The JBL N7000 (pro model 3105) is a vintage high-frequency dividing network designed to integrate ultra-high frequency (UHF) drivers, such as the JBL 075, into existing speaker systems to provide added "brilliance" in upper frequencies. It typically features a crossover point of 7,000 Hz. Schematic & Technical Composition

The Quest for the Blueprint: Everything You Need to Know About the JBL N7000 Schematic

If you have landed on this page, you likely fall into one of two categories. You are either a vintage audio enthusiast holding a dusty, non-functioning JBL N7000 crossover network, or you are a DIY speaker builder looking to clone one of the most legendary frequency dividers in hi-fi history. jbl n7000 schematic

Components: High-voltage non-polar capacitors and low-loss Orient Core coils. JBL N7000 Schematic Layout The JBL N7000 (pro model 3105 ) is

Unlike modern crossovers that cross at 1.5kHz or 2.5kHz, the N7000 crosses very high. In a three-way system (like the JBL Paragon or Hartsfield), the woofer handles everything up to 500Hz, the midrange compression driver (375) handles 500Hz to 7,000Hz, and the N7000 hands off everything above 7kHz to the tweeter. Complementary Power Transistors : The JBL N7000 employs

Uses an inductor in the serial signal line to roll off the lower driver (like the JBL 375) above 7 kHz. High-Pass Section:

  1. Complementary Power Transistors: The JBL N7000 employs complementary power transistors, which provide a high degree of symmetry and balance to the amplifier's design. This approach ensures low distortion, excellent linearity, and a wide dynamic range.
  2. High-Quality Capacitors: The amplifier features high-quality capacitors, carefully selected for their exceptional electrical properties and reliability. These capacitors play a critical role in filtering and regulating the power supply, ensuring a stable and noise-free operating environment.
  3. Precision-Resistor Network: The JBL N7000 schematic reveals a precision-resistor network, which provides a high degree of accuracy and stability to the amplifier's gain structure. This approach ensures optimal performance, low distortion, and a wide range of tonal options.

Visualizing the Signal Path

Signal Input (+) → L2 (0.30mH) → Midrange Output (+) ↓ C1 (3uF) → Attenuator Switch → L1 (0.20mH) → Tweeter Output (+)