Scientific Anglers Amplitude Smooth MPX

Power Meets Finesse—Now in a Silent, Slick Package.

The Amplitude Smooth MPX is a best-in-class all-purpose fly line designed to do everything a trout angler could ask for—and do it quietly. Built a half-size heavy with a front-biased taper, it loads modern fast-action rods with authority while still allowing for delicate dry fly presentations when it counts.

This line features SA’s AST Plus slickness additive, making it one of the slickest, longest-lasting coatings on the market—but in a smooth finish that slides silently through guides (no textured “zip” like the original Amplitude series). Whether you’re throwing hoppers, chucking nymph rigs, or punching into wind, MPX handles it.

🎯 Why We Like It

• Half-size heavy taper = quick rod loading

• Smooth coating for stealthy presentations

• AST Plus = extreme durability and slick shooting

• True do-it-all line for dry flies, nymphs, and small streamers

• Welded loops for fast leader swaps

🛠️ Tech Specs

• Taper: Weight Forward, MPX profile (front-loaded)

• Core: Braided multifilament

• Coating: AST Plus (smooth finish)

• Application: Freshwater

• Loops: Welded front and rear

🧠 Pro Tip:

If you liked the original SA MPX but want less noise and more stealth, this line is your upgrade. Pair with a 5wt fast-action rod for ultimate all-day, all-conditions performance—from dries to buggers.