JL Audio MV400/4i

Features
Digital Signal Processing
Connections
Specifications

Features

MVi Amplifiers: This JL Audio MVi-series amplifier is equipped with a 24 bit/48 kHz, triple-core AKM AK7738 digital signal processor (DSP) that allows you to configure and tune the amplifier inputs and outputs as needed. Using JL Audio's free TüN software on your computer, tablet, or smartphone, you can configure the amplifier from the driver's seat. (Using TüN software with your tablet or smartphone requires downloading the app from the Apple App Store or Google Play and adding the optional VXi-BTC Bluetooth Communicator.)

Controls: The MV400/4i 4-channel full-range Class D amplifier does not have traditional control knobs and switches for setup. Instead, the input sensitivity, crossover, equalization, polarity, etc. settings are configured using the TüN software.

Mounting: The keyhole slots on the flanges make vertical mounting easier (with the connections pointed downward), maintaining the amp's IPX2 rating.

Digital Signal Processing

AKM DSP: The AKM AK7738 Digital Signal Processing engine, when partnered with JL Audio's TüN software, gives you control over the configuration and settings of the amplifier. It is equipped with high-performance AKM A/D and D/A converters and offers independent tuning for each of the eight output channels (four amplified and four line out).

TüN Software: The free TüN software lets you configure, tune, and control your MVi amplifier from your laptop computer, tablet, or smartphone. The TüN software is available for Windows PC and Apple computers. TüN Mobile is available for iPad and Android tablets, while TüN Express works with iPhone and Android smartphones. Using TüN software with your tablet or smartphone requires downloading the app from the Apple App Store or Google Play and adding the optional VXi-BTC Bluetooth Communicator. The software allows saving up to ten tuning profiles for the amplifier.

Note: We strongly suggest you plan to use the full TüN program on your laptop or tablet. TüN Express on your smartphone offers a much more basic set of controls for the amp, detailed below.

TüN Input/Output Configuration: The audio signal for each of the eight outputs (four amplified channels and four line outputs) is independently set. Any of the four RCA inputs, or a combination (sum) of inputs, can be routed to a given output. The input level (gain) is also set in the TüN software.

TüN Tuning: Each output channel is independently tuned using TüN's equalizer, crossover, time alignment, polarity, and output level settings. The left and right channels can be linked together (default) or tuned separately.

• Equalizer: The 10-band EQ can be graphic or parametric. Each band is adjustable from -12 dB to +6 dB in 0.1 dB increments. The graphic EQ bands are fixed at 31 Hz, 62 Hz, 125 Hz, 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4 kHz, 8 kHz, and 16 kHz. The Q (width) is also adjustable in the parametric EQ.
• Crossover: Each channel has both high-pass and low-pass crossovers. When using the low-pass with a subwoofer, the high-pass can provide a subsonic filter. The crossover points can be set to any frequency, and the slope options range from 6 dB/octave to 48 dB/octave (12, 24, and 48 dB/octave Linkwitz-Riley and 12, 18, 24, 36, and 48 dB/octave Butterworth).
• Time Alignment: The output delay of each channel is variable in 0.02 ms steps. (Equivalent to approximately ¼".)
• Polarity: The polarity of each channel can be reversed (0° or 180°).
• Output Level: The output level of each channel is adjustable relative to the other channels in 0.1 dB steps.

TüN Express: Using the TüN Express App on your smartphone offers much less detailed control:

• Input: The only input option is 2-channel or 4-channel. The input channel assignments are fixed; you can't specify what input channel is routed to a given output channel. You also cannot combine two input channels for a single output channel. The input level (gain) is adjusted for each pair of inputs used.
• Equalizer: TüN Express offers no EQ function.
• Crossover: Each pair of output channels has both high-pass and low-pass crossovers. The slopes are independently adjustable (12 dB/octave or 24 dB/octave) and the crossover points can be set to any frequency.
• Time Alignment: TüN Express offers no time alignment function.
• Polarity: TüN Express doesn't offer the option of reversing polarity.
• Output Level: The output level of each pair of channels is adjustable relative to the other channels in 0.5 dB steps.

Power Output: The MV400/4i power specifications are as follows:

Connections

Power/Ground/Turn-On Terminals: The MV400/4i features a removable plug with screw clamp terminals for the power, ground, and remote turn-on cables. This allows you to pre-connect the wires to the connector, then plug it into the amplifier. The +12 volt and ground terminals will accept up to 4-gauge wire. (JL Audio recommends 4-gauge minimum.) The remote turn-on terminal will accept up to 10-gauge wire. (JL Audio recommends 18-gauge minimum.) The included 3mm and 2.5mm Allen wrenches are used to tighten/loosen the clamps.

Note: The amplifier is not equipped with a fuse. An external 40-amp fuse or circuit breaker (not included) must be installed on the power wire. If this is the only amplifier connected and a wiring kit is used with a fuse other than 40-amps, the original should be replaced with a 40-amp fuse.

Speaker Output Harnesses: Two pair of speaker outputs are connected to the amplifier, channels A/B and C/D. The plug on each set of wires mates to an included 10" speaker harness. The other ends of the harnesses have no terminal, just bare wire.

Signal Input: The amplifier has two pair of stereo RCA inputs that accept either pre-amp or speaker-level signals. When using a speaker-level input signal, use a speaker wire to RCA adaptor (sold separately) to connect the amplifier to the source unit via speaker wires. The signal inputs are configured using the TüN software. If one pair of inputs is not used, leave the factory cover installed.

Line Output: There are two pair of RCA output jacks, also configured using the TüN software. Leave the factory covers installed on any unused outputs.

USB: A Type B USB port is provided for connecting the amp to your computer and interfacing with the TüN software. A 6' Type A to USB-B cable is included.

JLid-COMM: This RJ-45 port is used to connect optional accessories:

• Bluetooth: VXi-BTC Bluetooth Communicator for wireless communication with Apple or Android smartphones and tablets
• Hub: MVi-HUB network Hub for connecting up to six MVi series amplifiers (ten with two MVi-HUBs); allows synchronizing DSP controls
• Remote: DRC-205 digital wired remote control; adjust output levels and DSP presets

Specifications

• Frequency Response: 12 Hz - 24 kHz (+0, -1 dB)
• Input Voltage Range (RCA inputs): 250mV - 16V RMS
• RCA Output Voltage: 4 volts RMS (maximum)
• Signal-to-Noise Ratio (20Hz - 20kHz):
  • At 1 watt: 80 dB
  • At rated output: 99 dB
• Damping Factor:
  • 50 Hz @ 4Ω: >100 dB
  • 50 Hz @ 2Ω: >50 dB
• Standby Current Draw: 2.4 mA