|RMS Power Output (Watts x Channels)||100 x 4|
|Peak Power Output (Watts x Channels)||—|
|Power at 2 Ohms (Watts x Channels)||120 x 4|
|Bridged Power (Watts x Channels)||240 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||20-20k Hz|
|THD at Rated RMS Power||0.1%|
|Signal to Noise Ratio||75 dB|
|Low-Pass Crossover Frequency||32-320 Hz|
|Low-Pass Slope (dB/octave)||12 dB/octave|
|High-Pass Crossover Frequency||32-320 Hz|
|High-Pass Slope (dB/octave)||12 dB/octave|
|Bass Boost Frequency||N/A|
|Speaker Level Inputs||RCA|
|Preamp Outputs||1 pair|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
Overview: The JBL GTR-104 is part of the GTR Stadium series of high-performance amplifiers. This full range Class D 4-channel amplifier will accept both high-level and low-level inputs. Class D amplifiers are highly efficient and compact, generating lots of power without drawing much current or generating heat. The GTR-104 includes Clari-Fi, an audio restoration feature that improves the sound of compressed digital files. The amp also includes a cabin-mounted control panel to give you amplifier control at your fingertips. The unit comes with spare fuses, speaker wire-to-RCA adapters, and mounting hardware.
Power Output: The GTR-104 delivers the following power output:
- 100 watts RMS x 4 at 4 ohms (<0.1% THD+N)
- 120 watts RMS x 4 at 2 ohms (<0.1% THD+N)
- 240 watts RMS x 2 at 4 ohms bridged (<0.3% THD+N)
Clari-Fi: Clari-Fi is a proprietary technology that analyzes compressed digital music files and improves them in real time. Using a predictive algorithm that restores audio content that is lost during the compression process. Clari-Fi provides extra bandwidth, especially in the high frequencies, widens the sound stage, and gives vocals a natural warmth not found in compressed files.
Control Panel: The amplifier comes with a wired control panel that provides numerous features not typically found with amplifiers. It has Bluetooth technology, and an omni-directional microphone for accepting and ending phone calls from your cell phone. Party Mode lets you pair multiple Bluetooth devices for streaming music from anyone’s phone. The control panel also lets you activate the Clari-Fi feature. The panel is 4-7/16″W x 15/16″H, and has a 19.5-foot cable. It can be flush- or surface-mounted with the supplied brackets.
ADAS: The GTR-104 has an interface for the Advanced Driver Assistance System (ADAS) that can override the audio source input to deliver a message or other audio from a connected ADAS accessory. On the amplifier, you can designate which speaker the ADAS signal is output: Front left, front right, rear left, or rear right.
Protection Circuitry: The amplifier features protection circuitry for thermal overload, over- or under-voltage (<9V or >16V), and short circuits. The LED on the top of the amp glows red if the amp goes into protection mode.
Controls: The GTR-104’s controls are located on one side of the amplifier. The rotary controls require a small screwdriver (not included) to make adjustments. The amp controls include:
- Gain: The rotary gain controls let you match the amp’s input sensitivity to the output of the source unit. The input sensitivity range of the amplifier is 0.2V and up for a low-level input, and up to 20V for speaker-level input. There are separate gain controls for the front and rear channels.
- Input Level: The Input Level switch lets you select the type of input you are using. For high-level input, there are two settings: Hi1 and Hi2. If the audio system fails to play with an amplifier connected to its output, or you get a “speaker disconnected” message on your factory stereo, set the switch to the Hi2 position. The Hi2 position includes a circuit design to fool this type of factory system into “seeing” a speaker connected to its output.
- Crossover: The amp features switchable crossovers that can be set to low pass (LPF), high pass (HPF), or Full Range. You can adjust the cutoff frequency of the crossover from 32Hz to 320Hz using the rotary control. There are separate crossovers for the front and rear channels.
Connections: The JBL GTR-104 uses set screw terminals for the +12V power, ground, and speaker outputs. The screws can be tightened/loosened with a Phillips-head or flat-head screwdriver (not provided). The amp connections include:
- Power/Ground: The +12V Power and Ground terminals will accept up to 4-gauge wire. It is recommended that you use 4 AWG power wire to the battery, with an in-line 60A fuse (or higher) installed no more than 18″ from the battery terminal. A 4 AWG ground wire (minimum) is also recommended, and attached to a metal area close to the amplifier.
- Remote Turn-On: The Remote turn on wire connects to the supplied plastic 2-pin Euro or Phoenix connector. The connector has tiny set screws to tighten the wire, and requires a precision screwdriver (2.4mm or 3/32″). The connector has “IN” and “OUT” terminals, allowing you to daisy chain the turn-on signal to another amplifier, if needed.
- Speaker Outputs: The amp features screw terminals for connecting four speakers. There are markings on the terminals for bridging the amplifier.
- Speaker-Level Input: The amp includes four bare wire-to-RCA adapters for connecting the amp to a factory radio or aftermarket head unit without preamp outputs. You should attach each speaker wire from the head unit to an adapter and plug the adapter’s RCA plug into the amp.
- Line-Level Inputs: The amplifier is equipped with two pairs of RCA inputs for connecting stereo RCA patch cables from the head unit to the amp.
- Pre-Out: A third pair of RCA jacks is provided to output the audio signal to a second amplifier, if desired.