The images for this post come from the original 1981 japanese brochure plus some from a Stereo Sound Best Product section and a january 1982 Stereoplay magazine.

A mint TA-E900 here.

TA-E900
(july 1981 - 1985)

The real big one, albeit a logical evolution of the TA-E88, by way of a prototype called... TA-E89 ! Sealed and potted modules (quite fashionable then :), dual-mono structure, super-select componentry, 99,99% pure copper, non-magnetic chassis, deported ALPS pots and selectors et al.

The E900 is electrically 95% an upgraded TA-E88 with an even simpler signal path (thanks to the modules) and minor circuit revisions ; even the sentence written at the back is identical to the one that was written on the E88 ! A little Sony twist is however present: the MC input is directly made for the PS-X9 and/or XL-55Pro and the 5,5Ohm input will be a problem with other moving coil cartridges - and that part of the circuit is potted in a module so no tweak possible! Well - if one could spend 15,000DM in 1982 for a TA-N900 and TA-E900 trio, I guess a PS-X9 didn't represent much of an addition to the final bill !
Also noted by Mirko Essling, the TA-E900's specs are slightly inferior to those of the original TA-E88's so, probably, Masaru Nagami's motto "only better sound matters" came in line here. It really isn't by much anyway but surprising nevertheless.

With the exception of the TA-D900 filter and, to a lesser degree, the TA-N900 monoblocks, Sony didn't sell that many of the other ESPRIT units and the E900 preamp is an x-rare object nowadays, the SE-P900 filter being even more difficult to find - perfection always comes in small quantities.