GRAND TOURING SERIES II ® gto75.2 II gto75.4 II gto755.6 II gto301.1 II gto601.1 II gto1201.1 II car audio power amplifier owner’s manual THANK YOU for purchasing a JBL Grand Touring® Series II amplifier. In order that we may better serve you should you require warranty service for your new amplifier, please retain your original purchase receipt and return the enclosed warranty registration card.
INSTALLATION WARNING: Playing loud music in an automobile can hinder your ability to hear traffic and permanently damage your hearing. We recommend listening at low or moderate levels while driving your car. JBL accepts no liability for hearing loss, bodily injury or property damage resulting from the use or misuse of this product. IMPORTANT: To get the best performance from your JBL Grand Touring® Series II amplifiers, we strongly recommend that installation be entrusted to a qualified professional.
APPLICATIONS – GTO301.1 II, GTO601.1 II AND GTO1201.1 II The GTO subwoofer amplifiers are single-channel amplifiers. There are two sets of terminals to make it easy to connect multiple woofers. Either set of (+/–) terminals may be used when connecting woofers. NOTE: For simplicity, Figures 2 and 3 do not show power, remote and input connections.
APPLICATIONS – GTO75.4 II + – + – The GTO75.4 II can be set up for stereo 4-channel, 3-channel or bridged 2-channel operation, as shown in Figures 6 through 8. + – NOTE: For simplicity, Figures 6 through 8 do not show power, remote and input connections. NOTE: Minimum speaker impedance for stereo operation is 2 ohms. Minimum speaker impedance for bridged operation is 4 ohms. GTO75.4 II (partial end panel) – + Figure 6. GTO75.
APPLICATIONS – GTO755.6 II Subwoofer Rear Right Front Right – – – + + + The GTO755.6 II can be configured for 6-channel, 5-channel or 3-channel operation, as shown in Figures 9 through 11. Input Mode Switch: • Use INT (internal mode) to send a signal from the front and rear inputs to the subwoofer. • Use EXT (external mode) when sending a dedicated signal to the subwoofer inputs; e.g., if your source unit has a subwoofer output. – + – Subwoofer Rear Left Front Left Figure 9.
INSTALLATION AND SETUP SETTING THE CROSSOVER(S) Determine your system plans and set the crossover mode switch accordingly. If you plan to use the GTO75.2 II or GTO75.4 II to drive full-range speakers, set the crossover mode to FLAT and skip to “Setting Input Sensitivity.” Initially set the crossover frequency control midway. While listening to music, adjust the crossover for the least perceived distortion from the speakers, allowing them to reproduce as much bass as possible. SETTING INPUT SENSITIVITY 1.
INSTALLATION AND SETUP To Neon Power Supply To Neon Power Supply Figure 13. Installing neon tubes in a JBL GTO amplifier.
SPECIFICATIONS GTO301.1 II • 204W RMS x 1 channel at 4 ohms and ≤1% THD + N • Signal-to-noise ratio: 77dBA (reference 1W into 4 ohms) • 294W RMS x 1 channel at 2 ohms, 14.4V supply and ≤1% THD + N • Dynamic power: 320W at 2 ohms • Effective damping factor: 6.39 at 4 ohms • Frequency response: 10Hz – 302Hz (–3dB) • Maximum input signal: 4.7V • Maximum sensitivity: 75mV • Output regulation: .098dB at 4 ohms • Dimensions (L x W x H): 11-5/8" x 12-5/16" x 2-3/8" • Fuse rating: 1 x 30A GTO601.