So you’ve finally made the plunge and bought yourself a cool new car. And, as one would expect, it came with a cool new radio. How do you retain that new OEM radio, and still build a killer aftermarket audio system around it? If you have an Audiomobile dealer nearby, it’s actually quite easy.
Because of products like the Audiomobile LDQ4, you can have your cake and eat it too. The LDQ4 is a small, but very high performance OEM interface that also doubles as a powerful line driver. At just $179.95, it also makes opening your wallet as easy as opening your options to all the aftermarket system upgrades you want.
The Audiomobile LDQ4 will accept input signal from virtually any OEM system. Gain is individually adjustable for the front and rear channels, and a two/four-channel switch allows you to drive the unit with four channels of input for full fading capability, or use only two channels of input with four channels of high performance audio output. Additionally, a wired remote level control can adjust the output level of the rear channels if you are using them to drive a subwoofer amplifier.
The inputs of the LDQ4 accept amplifiers rated up to 350 watts and feature fully-balanced differential circuitry for low noise and optimal amplifier compatibility. If your OEM radio does not have a remote-turn-on lead, the LDQ4 can be turned on by the DC offset found on the output of most BTL-type amplifiers, and a remote output function can be used to turn on multiple amplifiers. Another feature built into the LDQ4 is a specially engineered internal turn-off delay which eliminates the potential ‘pop’ noise when the system is turned off.
The output of the LDQ4 is truly high performance. Typical THD is less than 0.05%, and because the converter uses its own switching power supply, it can provide up to 9.5 volts of clean output signal to your amplifiers. Great output voltage is only useful when the output impedance is low enough to prevent ground loops, and in that regard, the LDQ4 has a very low output Z, at less than 50 ohms. This is a purpose-designed product, engineered by folks who understand car audio and the daily challenges faced in install bays around the world.
Should you only need two channels, there is also a two-channel version available with the same features, minus the remote level control function.
ON THE BENCH
I fire up my trusty Audio Precision analyzer and put the LDQ4 through its paces on the test bench. I’m happy to report that in every case, the unit actually exceeds the published performance specifications. Signal-to-noise measures well and frequency response is flat from below 10 Hz to well over 60 kHz. The measured output impedance is only 37 ohms, which is simply excellent. The signal-sense turn on works exactly as advertised, and the remote output terminal easily has enough current capability to trigger a typical Bosch or P&B relay. The wired rear channel level control provides 12 dB of level adjustment.
The Audiomobile LDQ4 is a high performance, high-to-low signal adapter, a true line driver, and the proper way to interface quality aftermarket audio gear with your vehicle’s OEM system. It’s a purpose-designed product that delivers, which is something Audiomobile has been known for since the beginning. If you own a newer car where retaining the OEM radio is your only option, check out the LDQ4 and the other Audiomobile processors at a dealer near you.