This paper is intended to give an overview of signal processing required for digital magnetic recording tape drives. It discusses modulation codes, write equalization, read equalization and finally a Viterbi or maximum likelihood detector used with a (1-D) equalizer in contrast to a traditional Peak detector.
Brahim Lekmine, Brahim Lekmine,
"Recording channel and data detection in magnetic tape drives", Proc. SPIE 2604, High-Density Data Recording and Retrieval Technologies, (15 January 1996); doi: 10.1117/12.230054; https://doi.org/10.1117/12.230054