NE5532 subwoofer preamplifier - low-pass filter, 12-24 V

Product Overview

• Amplifier module with low-pass filter for subwoofer applications
• NE5532 operational amplifier with adjustable filter cutoff frequency
• Input level up to 2 V, 10x gain
• Output signals exclusively in the bass range below approx. 200 Hz
• Bipolar power supply of +/- 12 V to +/- 15 V
• Small circuit board with 3.5 mm jack or RCA input

Product Description

The subwoofer preamplifier with low-pass filter processes audio signals by filtering out bass frequencies and boosting them specifically. The module uses the NE5532 operational amplifier, a classic low-frequency amplifier optimized for audio applications. The tenfold gain and adjustable filter cutoff frequency allow the bass response to be adapted to different room conditions and subwoofer characteristics without affecting the high frequencies.

The module accepts signals up to 2 V and amplifies them to up to 20 V; therefore, the output signal must remain within the supply voltage range of the connected subwoofer. The low-pass filter suppresses all frequencies above the set cutoff frequency, typically around 200 Hz. This protects the subwoofer from unwanted high-frequency components and reduces interference caused by near-field effects.

Applications include supporting existing active speaker inputs, for example when an audio interface or amplifier does not provide a dedicated subwoofer output. In home theater setups, the module provides the bass channel from stereo or multichannel sources. The module can also be used as a pre-stage in analog synthesizer setups with low-frequency modules, where preventive filtering prevents sound distortion caused by overloading.

Operation requires a bipolar power supply with at least +12 V and -12 V; a simple single-ended power supply will not work. The inputs are unbalanced (jack or RCA), but the output still requires a power amplifier or an active subwoofer with input sensitivity control. When operating with sources that have higher output power, the input impedance should be checked.

Safety Notice

The module is intended exclusively for building prototypes and for testing and development purposes. It is not intended for installation in the household power circuit or in consumer devices. Observe the required bipolar power supply and avoid short circuits at the outputs. If you are unsure about integrating the module into audio equipment or about the power supply, consult a qualified electrician.

Scope of Delivery

• 1x Subwoofer preamplifier NE5532 with low-pass filter, DC 12V-24V