Information about the target slopes :
- -1.05dB/octfor this site’s bright timbre target with standard loudspeakers (dome in high frequency and closed or bass-reflex box in lows) and in a mid size room, at a distance of about 3m
- -1.4dB/oct for this site’s balanced target and standard room/distance
- -1.75dB/oct for this site’s warm target and standard room/distance
- -1.75dB/oct with a prefered LF target similar to LFtarget = 205 (AES convention paper 8994) for the Harman slope (see Olive in AES papers)
- -0.8dB/oct above 200Hz for B&K recommendation dated 1974
- -1.5dB/oct above 1.6kHz with LF target = 304 for the Dolby Atmos Music target from 2021
- -1.2dB/octave for best corrections found in Sean Olive’s tests in EVALUATION OF ROOM CORRECTION PRODUCTS (see elsewhere in this FAQ)
- in studios, with more acoustic treatment and nearer listening position, the slope is generally less, ie between 0.8 and 1dB/oct
Another way to estimate optimal target slope is to use target curve calculator.
Hereunder is a graph comparing most target curves :
