Recording as hot as possible to maximize SNR was necessary for 16-bit recording but is counterproductive at 24-bit

A widespread outdated practice is recording signals as ‘hot’ as possible — close to 0 dBFS — to maximize the signal-to-noise ratio. This was rational in the era of 16-bit digital recording, where the restricted dynamic range made every bit count and noise floor was a real concern. At 24-bit resolution, the digital noise floor is roughly 144 dB below full scale — far below any meaningful concern. The dynamic range of a typical 24-bit interface (115–125 dB) matches or exceeds top analogue systems, eliminating any practical reason to chase hot levels. Recording at more moderate levels — with the same headroom used in analogue — is now correct practice.

Examples

16-bit recording: noise floor at -96 dB means leaving 20 dB of headroom gives only 76 dB of usable range — arguably too little. 24-bit: noise floor at ~-144 dB means 20 dB headroom still leaves 124 dB of usable range — more than enough.

Assessment

A recording engineer says ‘I always record at -3 dBFS peak to get the best signal-to-noise ratio.’ Is this advice correct for 24-bit DAW recording? Explain the trade-off they are making.