PreSonus HD9/HP4PACK Four-Person Headphone Monitoring Bundle 15 Inch Subwoofers then connect its individual XLR

then connect its individual XLR or 1/4-inch outputs to available mixer or PA inputs

and damped fabric surround

40 cubic feet gross internal volume

These options provide flexibility for systems using conventional speakers

PreSonus HD9/HP4PACK Four-Person Headphone Monitoring Bundle 15 Inch Subwoofers then connect its individual XLRThe PreSonus HD9 HP4PACK is a studio headphone monitoring bundle built for sessions where up to four people need to hear the same source. It combines one HP4 four channel headphone distribution amplifier with four HD9 closed back monitoring headphones. This setup helps musicians, producers, podcasters, and recording guests monitor together without relying on a single headphone output. The HP4 accepts a stereo line level source from compatible mixers,