My ADA is one of my most beloved pieces of gear. It’s analog flanging is pretty much unmatched by any device since. I’ve never heard a plug-in or digital emulation that came close. If you ever have a chance to buy one and the price isn’t insane…DO IT! There was also a re-issue products briefly in the 90’s but I don’t have any first hand experience playing one. Classic bucket brigade circuitry.

Especially cool to integrate with an analog synth since it also has voltage control!

Here’s a pic of my ADA: