On a linear scale, a change between two values is perceived on the basis of the difference between the values. Thus, for example, a change from 1 to 2 would be perceived as the same amount of increase as from 4 to 5.
On a logarithmic scale, a change between two values is perceived on the basis of the ratio of the two values. That is, a change from 1 to 2 (ratio of 1:2) would be perceived as the same amount of increase as a change from 4 to 8 (also a ratio of 1:2).
So a linear pot increases the volume evenly over its entire range of travel.
A log pot increases the volume to a lesser and lesser extent over it's range. So towards the top of it's range, turning the knob up a little only makes a very small increase to the volume, thus giving you finer control at louder volumes. For this reason log pots are often chosen for volume controls.
So I'd recommend you get a log version. The Alps Blue Velvets are reasonably priced and I think they're available from HiFi Collective and familygate on ebay. You'll also need a controller board and they're not cheap.
Source: Apple TV 4K - DAC: Beresford Bushmaster Mk II - Preamp: CI AudioPLC-1 Mk II - Power Amps: Musical Fidelity 550K mono blocks - Speakers: Wharfedale Opus 3 - Cables: Mark Grant etc - Misc: Belkin PF30 mains filters.