"Free Sound 4" is an energetic audio piece characterized by a dominating bassline that drives the track, setting a rapid tempo in line with the classic 'bpm' speed found in hardtechno music. The bass is distinct and slightly distorted, adding a raw edge to the rhythm and contributing to the overall hardcore theme. There's a hard and gabber-like intensity to the sound, indicating a trend towards the harder end of the electronic music spectrum. Amidst the heavy, pulsating beats, a melodic element peeks through, providing a touch of contrast and complexity to the otherwise relentless sonic assault. The track is devoid of any pauses, creating a mesmerizing, non-stop flow. It's a sound that's hard, loud, and designed to invigorate the senses.