Emulating the FATSO

The FATSO is often used to warm up digital recordings. The FATSO emulates Tape saturation, does high-frequency compression, creates low-frequency harmonics, and does leveling compression.¹ Marc Daniel Nelson says the warmth circuit is basically like a de-esser.²

For the first process, try something like Satin or Wow Control.

For the second process, try something like the high-frequency limiter on Limiter 6.³ Empirical Labs call it a dynamic low-pass filter, which I could make in Volcano 3.¹

For the third process, try something like a low-mid band with Saturn 2 using one of its transformer modes.

Finish it off with a leveling compressor like MJUC or Pro-C 2.