Kenwood - KT-1100SD - KX-780 Hi-fi set - Multiple models

(rare collector's items)
The Kenwood KT-1100SD is a high-quality Japanese FM stereo tuner from the mid-1980s, designed for serious hi-fi enthusiasts. It belongs to Kenwood’s better “audiophile” tuner lineup and is still respected today for excellent FM reception and sound quality.
Description

Produced around 1984–1987 in Japan, it is:

quartz synthesized digital FM tuner
FM-only model (no AM)
designed for high sensitivity and DX reception
built heavier and more seriously than many later digital tuners

Main specifications:

FM range: 88–108 MHz
Sensitivity: 0.95 µV
Signal-to-noise ratio: 86 dB
Distortion: 0.15%
Selectivity: 70 dB
Weight: 4.6 kg

Special features:

Wide/Narrow IF bandwidth switching
Variable audio output
Multipath outputs for oscilloscope alignment
Voltage/de-emphasis switching
Gold-plated outputs on some versions

Many enthusiasts consider it one of Kenwood’s hidden-gem tuners because of:

very strong reception
clean analog-like sound
upgrade/modification potential
Sound quality

Compared with average 1980s tuners:

noticeably more sensitive
quieter background noise
excellent stereo separation
strong performance in weak-signal areas

Among tuner enthusiasts, Kenwood KT-series tuners are highly respected.

The Kenwood KX-780 is a respected mid/high-end 3-head cassette deck from the golden era of cassette hi-fi, produced in Japan around 1985–1987. It sits above ordinary consumer decks and is still appreciated today by cassette enthusiasts for its sound quality and recording features.
Description

Main features:

3-head design (separate erase, record, playback heads)
Dolby B and Dolby C noise reduction
Manual bias adjustment
Real-time tape monitoring during recording
Full logic soft-touch controls
LED peak meters
Auto search/index functions
Microphone inputs
Timer recording capability

Technical highlights:

Frequency response:
up to 20–23 kHz with metal tape
Wow & flutter:
around 0.05%
Signal-to-noise:
up to 74–75 dB with Dolby C
Weight:
around 5–6 kg

The KX-780 was considered a serious enthusiast deck when new, priced around:

$355 USD in the mid-1980s
about 698 DM in Germany.
Sound quality

This is where the KX-780 stands out.

Compared with normal 2-head decks:

better recordings
more accurate monitoring
cleaner high frequencies
stronger stereo imaging

Period lab reviews praised:

extremely flat playback response
very good Dolby implementation
high-quality transport control system.