Pioneer CT-91

The CT-91 is less remembered than its subsequent CT-93 version.

If the Reference Master Mechanism and motors are the same (but probably somewhat revised from the CT-A9 1980s biggie), the main differences lie in the electronics and absent functions : no Super Auto BLE and no Dolby S !

Super Auto Ble is Pioneer's tape analysis system for automatic bias & eq settings - manual on the CT-91 and rather compared to the CT-A1.
The erase head also was here a basic ferrite but the rest was kept the same for the next version :
cast-iron transformer, honeycomb copper-plated chassis, honeycomb feet, single-crystal oxygen-free copper wiring, select componentry and three-piece honeycomb cassette stabilizer (as in Sony's contemporary TC-K990ES).
The rec/play heads are Laser Amorphous - as in the CT-A9D revised version of the CT-A9.

The original version was the japanese T-818 - non Elite, of course.