The other big one - the rich, very rich amateur's deck. Adorned with cool frills like PPM meters, a notable example of elegance in design AND the same build quality as any explicitly professional deck.
The TC-880-2 was (and still is) a half-track recorder/player, could spin tape at 19 and 38cm/s, had (and still has) four F&F heads, DD motors, Closed-Loop/Dual-Capstan, a real-time counter (at 38cm/s), Uniphase trickery and 36kg on the balance.
According to my japanese tech report from 1978, frequency response of the TC-880-2 skyrockets at 50Khz with no attenuation at all.
Sold in Japan under the TC-8750-2 moniker for the royalty-like sum of 550,000¥.
For the sake of comparison, the big TC-756-2 cost 180,000¥ and the monster TC-9000F professional half-track only 260,000¥ !
Unlike other big Sonys, the TC-880-2 was only available as half-track - prestige oblige. It also was clearly planned as a two-box item (drive + electronics) but finally put in a single enclosure.
I have no idea of the production run : the highest serial numbers spotted so far are #10 500 (UK) and #10 544 (DE).
According to Sony's fairly logic s/n system, the 5-digit serial starting with a 1 denotes professional destintion.
This means there were very few made, all in one run in 1974, the bulk being quietly sold until the last samples got discounted circa 1979/1980 and as late as 1982 for the US.
If we assume 600 were made, there must be very few surviving samples...
What is oft forgotten about Sony is that its early successes came from tape recorders : Sony's TapeCorders (...TC) always sold well, were well reviewed and found their way into many a studio, whether audio or... video.
Sony quickly became the undisputed leader in the video field - a position still held today since the era of 2" video.
Sony's early digital audio decks (whether PCM or integrated) became worldwide standards, just like the PCM-3324 and PCM-3348 became worldwide industry standard, just like DAT became a professional standard, just like the professional Betacam became a worldwide standard, just like DV became a worldwide standard and this time for both consumer and pro sides of the market.
No matter how you hate hearing that, all the news you're watching on TV and all the video masters that hold movies (and their soundtracks) and the vast majority of albums recorded throughout the 1980s and 1990s were done, edited and mastered on Sony tape equipment, whether DASH or DAT PCM, DV-Cam, Beta SP or DigiBeta.
Anyway - Sony's big "pro-sumer" open-reel may not have been marketed as much as the likes of TEAC, Akai or Technics but they were just as good.
Sometimes even better :)
Problem is : Sony never really cared to advertise about them, busy as it was cornering the real professional market !