How to create this kind of wave gradient effect

Question

I'm attempting to create a similar effect to the one in the image below, however everything from the increasing size, to the smooth gradient across all the objects is proving to be difficult.

I've tried blending and then replacing the spline but the distance was not equal and I couldn't scale the size horizontally. Also, I tried to give each individual object its own gradient as well as tried to make a clipping mask, but both results weren't successful.

I'm relatively new to illustrator and graphic design, so I would really appreciate the insight.

Answer 1

You could use a blend.

Here's the blend I made in outline mode. I made one ellipse and duplicated them, stretched some and squished others making sure they were all equidistant. I edited the spine manually to make the curves. You need to watch the handle lengths as these impact on the spacing of the blend.

Fill each of the four pieces

Alternatively, you could Expand the blend, ungroup and convert to a compound path. Then add a gradient at an an angle.

Answer 2

This isn't really much different than what other's have posted..

... but I did want to point out that you can merely add a new fill via the Appearance Panel to the group created by expanding the Blend and assign the gradient to that fill. This allows you to dive into the Group and further edit the strokes as strokes. Meaning you can change their width or profile more easily.

In other words, you don't really need to expand the strokes themselves, just the Blend.

Answer 3

Maybe another way to do it :

I start with some lines with strokes to build it

Then, i select all and go for this pathfinder (you may add stroke and ungroup the result)

Delete the unwanted part, chose a stroke profile

And finally, Outline the strokes to add the gradient

The problem with this method is if you need rounded shapes, instead of pointy ones.