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In talking about "spoon shaped concave" as Balargue said, I am usually thinking of the side to side concave that is molded in to the kicks, as well as the rise from the bolts up to the tip, more so than overall shape, eg spoon shaped kicks looking down from above, as in pointy looking ends of a board.
I also had a look at the HLC shapes and they sure do have a lot going on there, which is good to see, but I also wonder how many people get a little lost looking at that. What constitutes mellow (low concave), medium and steep (high concave) to different brands?
For a while, I have been trying to work out a fairly even guide to concave of boards, as some people say my boards are extremely flat, with a more regular board feeling very steep to me, then a steep mold feeling ridiculous, so it is all down to personal opinion as to concave and things.
Using an angle finder and measuring side to side, as well as angle of kicks seemed to be the easiest way, but even then, what I measure might not be relatable to others, eg side to side concave under 10 degrees is comfortable, end kicks around 20 works well for me. Some boards are upwards of 24 to 25 in the kicks and 12 to 13 side to side. On the flip side, kicks down around 16 or so feel extremely flat, as does concave under 7 degrees side to side, but these are all just numbers until someone can stand on a board to feel it and then translate it to what they are used to.
At some point I was even going to make up some sort of numbers guide, but then sort of gave up on it, mainly because there can be such differences in anything that is not single pressed.
I do see from the "About" page, that HLC presses all boards individually, so that is also a plus, ensuring everything is more uniform.