What’s the best audio effect to start with when learning audio programming?

If you're getting into audio DSP, a surprisingly good first effect to build is panning.

It seems simple, but it introduces a lot of core ideas:

• Turning mono into stereo
• Gain scaling for left and right channels
• Linear vs equal-power panning
• Real-time processing

It’s easy to implement, but it forces you to think about signal flow and stereo space, which are fundamental in audio programming.

From there you can extend it into things like auto-panning, LFO modulation and stereo widening.

Curious what others started with when learning DSP.
Was panning your first effect or did you build something else?