Materials have some combination of the four basic acoustical properties: Absorption, Diffusion, Reflection, and Transmission. Materials vary in their performance of those properties with respect to frequency. Cork is absorptive only at relatively high frequencies but is very damped with respect to transmission. A flat cork wall does little if anything to help reflection and diffusion.
Adding a floating layer of sheetrock hung by Z-clips to the adjoining walls, and edge sealed with acoustic caulking will reduce noise transmission between units, and if possible, is strongly recommended.
Within the room, acoustical panels help control unwanted reflections via absorption, as will a heavy carpet. Diffusers, as the name implies, help scatter sound without absorbing it. Bass traps help reduce low-frequency standing waves.
Two to four sidewall acoustical panels, 2' X 4' and a pair of bass traps would probably significantly improve your overall sound . My own preference is Acoustimac for choice, cost and customer service.
Adding a floating layer of sheetrock hung by Z-clips to the adjoining walls, and edge sealed with acoustic caulking will reduce noise transmission between units, and if possible, is strongly recommended.
Within the room, acoustical panels help control unwanted reflections via absorption, as will a heavy carpet. Diffusers, as the name implies, help scatter sound without absorbing it. Bass traps help reduce low-frequency standing waves.
Two to four sidewall acoustical panels, 2' X 4' and a pair of bass traps would probably significantly improve your overall sound . My own preference is Acoustimac for choice, cost and customer service.