Teac X-1000R
Teac X-1000M
Teac X-1000
(1981 - 1985+)

Along the ultimate X-2000 series, the X-1000 recorders were the penultimate consumer reel-to-reel decks to be manufactured - although the format was rapidly dying, these sold very very well.

Although the R version is the most common, the M should be the most desirable : M stands for Master and that means half-track recording at 38cm/s. The S version (more often named simply "1000") is an R without auto-reverse but with type II dbx ! All three available in silver or black, with or without a wooden enclosure, and all weighing... too much !

The dbx system allowed for a stunning 100dB s/n ratio and dynamic capabilities which only CD could surpass - or so we were told ;-)
Darwinistic evolution oblige, all three are part of the elite of open tape recorders... TEAC oblige, too.

The X1000M was the last consumer reel-to-reel recorder to remain available, with the X-2000M which outlived it by a few years.

Btw, I own a NOS black X-1000RW :)

X-1000R
4-track autoreverse, 6 heads, dbx type 1
X-1000M
2-track with 2 & 4-track replay, 3 heads, dbx type 1
X-1000
4-track, 3 heads, dbx type 2

Speeds
9,5 & 19cm/s: 1000R & 1000
19 & 38 cm/s: 1000M

X-1000RW = 1000R + wood case
X-1000BL = 1000 in black + wood case

TZ-650 = acryl transparent cover
RC-100 = wired RM (1000R)
RC-90 = wired RM (1000 & 1000M)

A very informative Audiokarma thread.