Hearing Damage Timer dBA dBC — dBA (−10 dB offset applied) Current SPL level dBA NIOSH (3 dB) — OSHA (5 dB) —
RT60 Estimator Audience (seated) people Floor Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) Ceiling Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) Front Wall Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) Back Wall Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) Left Wall Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) Right Wall Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) Speech intelligibility: — Music suitability: — 125 Hz 250 Hz 500 Hz 1k Hz 2k Hz 4k Hz RT60 empty (s) — — — — — — RT60 occupied (s) — — — — — —
Treatment Sizing Additional absorber area (m²) needed to reach a target RT60 Target RT60 s Material Concrete/brick (unpainted) Concrete/brick (painted) Plaster (smooth, hard wall) Plaster (rough / sprayed) Drywall / gypsum board Glass (large pane, mounted) Wood floor (hardwood, on joists) Vinyl / linoleum floor Carpet (thin, on concrete) Carpet (medium, on foam pad) Acoustic foam (25 mm / 1 in) Acoustic foam (50 mm / 2 in) Suspended acoustic tile Heavy curtain / drape Upholstered seating (area) Perforated panel (25 mm air gap) 125 Hz 250 Hz 500 Hz 1k Hz 2k Hz 4k Hz Area (m²) — — — — — —
Air Absorption ISO 9613-1 approximation Distance m Temperature °C Humidity % 2 kHz — 4 kHz — 8 kHz — 16 kHz —
Sub Polarity Check Sub-to-top distance difference m Crossover frequency Hz Phase offset — Enter values to check polarity.
Crossover Reference Crossover Sub slope Top slope Typical use 80 Hz LR24 −24 dB/oct −24 dB/oct Club / small venue 100 Hz LR24 −24 dB/oct −24 dB/oct Medium venue PA 120 Hz LR24 −24 dB/oct −24 dB/oct Festival / large PA Custom notes