JBLメーカーGTH400-20107の使用説明書/サービス説明書
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GTH400-20107 06/03/98 15:49 Side 26.
GTH400 GTH400 6/5/4/3 CHANNEL AUTOMOTIVE POWER AMPLIFIER OWNER’S MANUAL GTH400-20107 06/03/98 15:49 Side 1.
T able of Contents 1. Introduction ...................................................................................... 3 1.1 Features .................................................................................... 4 1.2 About Installation ....
3 1. Introduction Thanks for purchasing your new GT series automotive multichannel ampli- fier. Your GT series amplifier will easily connect to virtually any car audio system, whether it is factory installed or one purchased separately. The GTH400 includes an abundance of unique features which are described in this manual.
4 1.1 Features Theory of Operation – Virtual Center Image Enhancer JBL’s breakthrough “Virtual Center” circuitry is the result of the understanding of how the human ear responds to timing, frequency, and amplitude cues to determine the apparent direction of a sound source.
5 2. Installation and use Refer to the “Crossover Frequency Adjustments” and “Speaker-Level Input Impedance Adjustments” sections of this manual to see if you will need to make alterations to their factory settings. 1. Disconnect the negative cable from the battery.
3. System Design Using the GTH400 3.1 Speaker Requirements When used in the non-bridged mode a group-channel of the GTH400 can easily drive two 2-ohm speaker loads. When only one speaker is connected to the left and right outputs of a group, virtually any conventional speaker may be used.
7 3.2 Typical Applications The diagrams on pages 8 & 9 show the most common basic system configurations of the GTH400. One or more of these building blocks may be combined to form elaborate system designs. The GTH400 uses the terminology “Group 1,” “Group 2” and “Group 3” to indicate the three main signal paths within the amplifier.
8 L L R L R + L – Application 4 3-Channel Bi-Amplified 4-Channel Input (Fading Subwoofer) L L R R GR 1 GR 3 GR 2 Group 1 Group 2 Group 3 Input Mode L L L+R Group 2 Input – GR 2 – Group 3 Input .
9 4. Installation and Use 4.1 Controls and Connectors 1. Preamp-Level Input Connector – Use these connectors for line (pre- amp) level inputs to the amplifier. 2. Preamp-Level Output Connector – Use these outputs to send signal to additional amplifiers.
10 to use in conjunction with a high- pass filtered input signal to create a bandpass crossover (for a midrange or midbass driver). Set the switch to H (high) to activate the high-pass filter for use with satellite speakers or tweeters on an amplifier group.
11 + - + - + - Buffer Buffer Buffer Buffer Buffer Buffer 1 2 3 1 2 3 1 2 3 1 2 1 2 1 2 3 1 2 3 1 2 3 1 2 3 CH. 1 L IN CH. 1 R IN CH. 2 L IN CH. 2 R IN CH.
12 4.2 Internal Adjustments Speaker-Level Input Impedance Adjustments The speaker level inputs of the GTH400 come factory set with 100k ohm input impedance. This will provide the lowest distortion operation from the speaker outputs of most modern head units by reducing the power the amplifier in the head unit must deliver to practically nothing.
13 Custom Chip Construction Regardless of whether you build or buy it, the necessary resistor network has the following configuration: • Each resistor in the package has the same value.
14 Under-Dash Remote Installation 1. Set the GTH400 remote in the installation location and mark two mounting screw hole locations. 2. Set the GTH400 remote aside and drill two pilot holes using a 1⁄16"- (1mm) bit. Be careful not to drill into any of the car’s components.
15 FACE PLATE DASH PANEL SPACER PLATE (INCLUDED) FACE PLATE Cassette/CD Tuner CD Player or Changer CD Input Cassette/CD Preamp Output Antenna Input Power Antenna Power Antenna Relay Blue w/White Strip.
16 is heat- and oil-resistant whenever running wires through the engine compartment. All wire-to-wire connections should be soldered and insulated with heat shrink tubing, or connected through a high-quality insulated crimp-on connector or secure set-screw-type terminal blocks.
17 • The GTH400 will draw as much as 60 amps from the vehicle’s electrical system, enough to overload conventional vehicle wiring. Therefore the +12 volt power supply must be taken directly from the positive side of the battery. Do not connect to the vehicle’s fuse block or to a wire feeding other accessories.
18 background noise levels in the system low. • To adjust a system using a single GTH400, start with all three of the amplifier gain controls fully counterclockwise and the Imaging Enhancer Remote set to “Bypass” mode. Some head units have additional output level controls or switches.
19 position for driver-optimized sound stage. 5. Proceed to push and pull the Rear- Ambience knob to hear the effects of “Driver” and “All” modes. You should hear imaging coming from the middle of the dashboard when the knob is pushed in (“Driver” mode).
20 and off, or does not work at all, a problem in installation or an abnormal electrical condition is indicated. Check speaker wiring for short circuits or impedance loads significantly below 2 ohms (4 ohms in bridged mode). Check the power supply voltage at the input of the amplifier to be sure that it is normal; between 11 and 16 volts.
21 7. In Case of Difficulty Power-on light does not come on • Head unit not on; turn the head unit on. • Ground wire is disconnected or defective; check for continuity with an ohmmeter between the amplifier’s ground terminal and a known chassis ground point.
22 Power light is on, but no sound is heard • Defective head unit or signal processor; from some or all of the speakers check each component for proper wiring and operation. • Defective GTH400; If there is audio signal present at the inputs of the amplifier and there is no output, the GTH400 may be defective.
23 8. Specifications GTH400 35 Watts x 4 + 70 Watts x 2 (4 ohms, 0.05% THD) 50 Watts x 4 + 100 Watts x 2 (2 ohms, 0.08% THD) 100 Watts x 2 (Bridged 4 ohms, 0.08% THD) + 70 Watts x 2 (4 ohms, 0.05% THD) 100 Watts x 2 (Bridged 4 ohms, 0.08% THD) + 200 Watts x 1 (Bridged 4 ohms, at 0.
24 9/64" (3.5mm) in 4 places 9/64" (3.5mm) in 2 places 25/64" (10mm) drill in 2 places UP UP Remote Control Drilling Template Power Requirement 11 to 16V DC Negative Ground Fuse Size 30.
25 Staple or clip your original bill of sale here. ▼ GTH400-20107 06/03/98 15:50 Side 25.
デバイスJBL GTH400-20107の購入後に（又は購入する前であっても）重要なポイントは、説明書をよく読むことです。その単純な理由はいくつかあります：
JBL GTH400-20107をまだ購入していないなら、この製品の基本情報を理解する良い機会です。まずは上にある説明書の最初のページをご覧ください。そこにはJBL GTH400-20107の技術情報の概要が記載されているはずです。デバイスがあなたのニーズを満たすかどうかは、ここで確認しましょう。JBL GTH400-20107の取扱説明書の次のページをよく読むことにより、製品の全機能やその取り扱いに関する情報を知ることができます。JBL GTH400-20107で得られた情報は、きっとあなたの購入の決断を手助けしてくれることでしょう。
JBL GTH400-20107を既にお持ちだが、まだ読んでいない場合は、上記の理由によりそれを行うべきです。そうすることにより機能を適切に使用しているか、又はJBL GTH400-20107の不適切な取り扱いによりその寿命を短くする危険を犯していないかどうかを知ることができます。
ですが、ユーザガイドが果たす重要な役割の一つは、JBL GTH400-20107に関する問題の解決を支援することです。そこにはほとんどの場合、トラブルシューティング、すなわちJBL GTH400-20107デバイスで最もよく起こりうる故障・不良とそれらの対処法についてのアドバイスを見つけることができるはずです。たとえ問題を解決できなかった場合でも、説明書にはカスタマー・サービスセンター又は最寄りのサービスセンターへの問い合わせ先等、次の対処法についての指示があるはずです。
