https://en.wikipedia.org/wiki/Echoic_memory 4. seconds. It's all you have to discern a 'high-end' component from another one. Try listen analytically to 2 components of your favourite gear. Stop to switch cables and you have lost it. Stop to switch headphones and you have lost it. Stop to compare a DAC vs. another and you have lost it. Stop to compare a DAP vs. another and you have lost it. Stop to compare ... & ... and you have lost it. 4. seconds. Imagine that 90% of the 'audiophile' scene was based on the inability to factually check sound quality within that 3-4 seconds maximum window of opportunity. Imagine everybody despises 'ABX tests"... Imagine an ocean of snake oil... Imagine... P.S.: I just bought me this & this.