Fly Line Review: Scientific Anglers Amplitude Smooth – Infinity Taper

I’m feeling spoiled. Genuinely spoiled. Putting a new fly line on a reel is such a great feeling. It is a magical feeling that left me feeling, like I said, spoiled! A quality new fly line makes such a difference over an old, cracked, beaten, and heavily used fly line. Don’t believe me? Here’s what I HAD.  It had been used hard in some urban fishing and repeatedly on small streams where it came in contact frequently with various types of trees and was stripped/dragged past countless rocks.

See, I told you it was beaten up. Honestly, I probably should have replaced this line quite a while ago – but as I’ve spent most my time fishing heavily with either a 3wt or an 8wt replacing this line was not urgent. Now, I’m wishing I had done it earlier. Like I mentioned a quality line can make all the difference in casting, fishing, and overall enjoyment.

I replaced my old line with the new Scientific Anglers Amplitude Smooth with AST Plus Infitinity taper WF 5wt line.  Side note: I recommend swapping lines while at a fly shop instead of doing it while in the passenger seat while your dad’s buddy is driving with you to the river – but I did manage to do it with no issues which was an awesome surprise.

So, you might be asking, “What is AST Plus?” Well, let me tell you. The AST stands for Advanced Shooting Technology.  The Plus, well, that is the new and improved version. In simpler terms its the new slickness additive that Scientific Anglers adds to the line to increase slickness (nearly 70% slicker than the closest competitor, according to their website). This slickness, or reduction in friction, makes it easier to cast and last longer than ever before. SA claims that line can last over 862% longer than the closest three competitors! That is definitely an impressive stat for a fly line! Here are my thoughts and experience with the Amplitude Smooth line:



This line is smooth! That is something that I really enjoyed on my last few trips using this line. I have been using textured lines and I found that stripping streamers with a smooth line feels so much better on my fingers when compared to the textured lines rubbing over my fingers. After a couple hours of fishing streamers on this line I didn’t notice any discomfort – which definitely is a good thing! This also combines to make a much more quiet experience. Having fished textured lines and the smooth version on mountain streams this summer, I found this line to be extremely quiet and more enjoyable.

Easy to Cast:

I was super impressed with the castability (I don’t know if that is a real word or not, but let’s go with it, k?). I spent time throwing a couple of different styles of flies to see how the presentation felt with this new line. I threw some decent sized (size 4 with an 20mm articulated shank) mouse patterns, some weighted streamers, a wind resistant bass fly, and some dries.  I was impressed by the ability to launch these heavier and more wind resistant flies and also with the delicacy that this same line presented some dry flies (although if I was throwing “big” streamers and mice much more than I currently do, I might recommend a slightly more aggressively tapered line). I was able to generate some distance with some roll casts in a difficult to cast area. This line was so easy to cast.

Color Change:

There are a lot of lines that are multi-colored. This is a big plus, in my humble opinion.  I really like being able to tell where I am in my fly line by knowing what color of line I am holding. This gives me a better perception as to distances being cast, how far the fish is running, and where tapers are changing in the line. This particular line comes in two tri-color options: Bamboo-Buckskin-Camo and Optic Green-Mist Green-Bucksin. (These colors go from Running Line – Rear Tapers/Belly – Front Taper or Back – Middle – Front End/Tip if that makes more sense).  The Front Taper is roughly at 10 feet, the Belly and Rear tapers go from around 10 feet to 50 feet and the running line is from 50 feet to the end at 90 feet.



This particular line is meant to be a general, “jack of all trades” style line. That is hardly a complaint, I get it. This line is meant to be used in as many as possible different situations. It is for lack of a better way to explain it, this line is the “5wt rod” of fly lines. It does pretty much everything and can be used in most circumstances. It wasn’t designed to specifically chuck the heaviest nymph setups or the biggest streamers, but it is meant to do a great job at helping us accomplish the majority of regular casting duties that we as fly fishermen tend to find ourselves trying to accomplish. There are definitely times and places for general do everything lines and very application specific lines. Like I said, that’s hardly a “Con” of this line, but it is important to know.

Overall, I really like this line and I can’t wait to see if I can validate the longevity claims for this line! I know I’ll be using it regularly to throw some hoppers to trout and some small-to-medium sized streamers for some bass.  A new fly line is a great way to invest some money into having a better experience on the water! Tight lines and wet nets, my friends!