What is it?
The LoC™ 22 is a fully active, two-channel line output converter, designed to convert speaker level signals to line-level signals at its RCA outputs. It also provides a turn-on signal for aftermarket amplifiers.
It features:
- 2 channels of input, up to 40 V RMS per channel (400 watts at 4 ohms), via Euro-block connector
- 2 channels of output, up to 8 V RMS unclipped, per channel, via RCA jacks
- Auto Turn-On, via signal sensing or DC-offset sensing
- Switchable input impedance:
- 20 kΩ or 60 Ω, per channel
- Adjustable Output Level:
- 1 V - 8 V per channel
What makes it special:
- Extremely clean audio performance
- Easy setup
- Compact size
- Affordable
- Incredibly useful
What is it good for? Lots of things!
1) Add a subwoofer to a factory audio system.
The LoC™ 22 is ideal for adding a subwoofer amplifier to a factory audio signal. Unlike passive line output converters, the LoC™ 22 will handle high input voltages and preserve the full low frequency response of the factory signal at all listening levels.
2) Connect any amplifier or processor to a high-power factory audio signal.
The LoC™ 22's super-clean, analog circuitry is ideal for stepping down the level of any full-range factory audio signal that is too powerful for direct input to an aftermarket amplifier or system tuning processor.
The following are maximum input levels for JL Audio amplifiers and tuning processors. Use an LoC™ 22 whenever factory amplifier's output signal exceeds these levels.
JX: up to 10 V RMS (High-Level Inputs)
MX: up to 15 V RMS (High Input Range)
RD/XDv2/Slash v3/HD: up to 8 V RMS (High Input Range)
VXi: up to 16 V RMS
TwK™ 88: 7.1 V RMS
NOTE: If the factory signals require frequency response correction or summing, consider a FiX™ 82 or FiX™ 86 instead.
3) Prevent factory amplifier muting due to high impedance.
The LoC™ 22 features a switchable input impedance, from 20 kΩ (high) to 60 Ω (low). The low position is designed to present a thermally protected low impedance load to factory amplifiers that mute outputs at higher impedances. (It's much like a built-in FiX-LSA-4).
4) Provide turn-on signal to a system.
The LoC™ 22 offers two distinct Auto Turn-On modes:
DC Offset: This is the preferred mode, detecting the small amount of DC current present in many factory audio signals, and switching the +12V turn-on output on/off immediately, as the factory amplifier turns on and off.
Signal-Sensing: This mode is used when factory signal contains no DC offset. It senses the audio signal and, once this signal climbs above a certain threshold, activates the +12V turn-on output. Turn off this is automatic after about 1 minute of no signal detected.
Frequently Asked Questions:
Why does the LoC™ 22 not include a port for a level control knob?
Remote Level is best controlled at the amplifier, and almost all JL Audio amplifiers have level control ports for HD-RLC, RBC-1, or DRC controllers. For this reason, we did not include one in the LoC™ 22.
Why does the LoC™ 22 not offer a bass correction feature to combat the bass limiters found in many factory audio systems?
Bass correction features rely on an estimate of the factory volume setting, based on the signal level present at the inputs of the LOC. This is an inexact method when playing music that is not only dynamic in nature, but also varies widely in average level from one recording to another. We find that these correction circuits can result in erratic bass correction behavior.
A better approach is to find the volume setting at which the factory audio system begins to limit bass, and then set up the audio system's gain structure so that it plays loudly at or below that level. This neatly sidesteps the factory audio limits without any erratic effects. Most factory systems remain linear to about 75% of their volume range, so adjusting the system gains for lots of loud, clean output at 75% volume will accomplish the task.
Can two or more LoC™ 22s be used as summing pre-amplifiers?
This is not the product's design mission and is not recommended. If you have signal summing needs, we recommend that you use a FiX™ 82 or FiX™ 86.
This fantastic little nugget of analog audio processing was designed by JL Audio Sr. Engineer Bruce Macmillan.