Channeling causes mixed extraction in one shot, leading to sour and bitter notes together. Better puck prep is often the fastest quality upgrade.
Break clumps before tamping
Use a thin-needle WDT tool to distribute coffee evenly throughout the basket.
Focus on corners and edges where density differences often form.
Keep basket fill and headspace consistent
Inconsistent dose headspace changes flow resistance and flavor balance.
Stick to one basket and one dose target while learning your process.
Tamp level and calm
A level tamp matters more than brute force. Press evenly and keep wrist alignment steady.
Avoid knocking the portafilter after tamping, which can crack the puck.