Tuning your audio equipment is one of the most important things you can do. With an amplified system, if you don’t set your gains properly, you could end up with poor audio. Adjusted the right way, your speakers will sing or scream depending on what you’re looking for. 

A monoblock amplifier is often used to add a single subwoofer to your pre-existing speakers. Thes amps will come with features to specifically shape the sound of your bass. 

Improper tuning can create distortion, which can sound like buzzing, crackling, hissing, whomping, and various other noises that intrude on the instruments of your music. Too low and you’ll be greeted by the hiss of background noise; too high and the music will be accompanied by distortion and clipping. 

NVX VAD17001

A gain level is not a volume knob, it controls the level of power being delivered to the subwoofer. Gain is the ratio between the volume at the input and the volume at the output of an electrical circuit. 

Setting the gain will ensure your sub is getting the right flow of energy without blowing it up. With your volume up to 75%, turn the gain knob up until you hear distortion. Back off on the gain roughly 5-10%.

Subsonic Filter

This filter prevents any frequencies that are not audible to be blocked. This filter is usually set around 20 Hz. It acts as a safeguard to keep from damaging your subwoofer. 

Bass Boost

Can either be displayed at a fixed “on/off” or variable from 0 – 12dB. With a controllable boost, it will give that extra kick to the bass frequency you selected. If it’s fixed, it’ll always give a 12dB boost at 45hz.

Bass Frequency

Variable from roughly 40-100Hz. This is the frequency that will receive the boost. 

Low-Pass Filter

This allows the low frequencies to pass or be allowed to play by setting the “ceiling” of the frequency band. This feature is used mainly for subwoofers. The low frequency spectrum will contain any frequency of about 100 Hz or lower.


This feature ensures that the sound from your subwoofer reaches you at the same time as your speakers. For example, if you are hearing an echo, you should set your phase to 0. This feature is adjustable from 0-180 degrees.

Read On: How to Adjust Amplifier Gains using a Digital Multi-Meter