Speeding up a loop to resample it then returning to the original tempo adds authentic grit

A classic hardware sampling technique involves recording a loop at a high tempo (which speeds up the sample, changing its pitch and adding harmonic compression artifacts), then playing the resulting recording back at a slower tempo so it returns to the original pitch. In Ableton, this is done by increasing the project tempo to ~180 bpm while the loops are in Re-Pitch mode, recording the mixed audio to a new track (resampling), then returning the project tempo to the target (e.g., 140 bpm). The resampled audio has acquired subtle artifacts from the speed change that add a vintage, hardware-sampler quality not achievable by merely changing warp modes.

Examples

Target tempo: 140 bpm. Set project to 180 bpm (loops in Re-Pitch, so they play faster/higher). Resample the output to a new audio track. Return to 140 bpm. The resampled file now plays at 140 with the timbral character it had at 180 baked in.

Assessment

Explain the purpose of the ‘speed up then resample then return to original tempo’ technique. What sonic difference does it create compared to simply playing the break at 140 bpm from the start?