Technics SU-7700II Integrated Amplifier, Matsushita Electric Industrial

【I've uploaded a recording of the sound produced by this amplifier.
"https://www.youtube.com/watch?v=SxyBVd0SDX4"
You can listen to it from the link above.】

○ Power relay contact cleaning
○ Board cleaning and partial re-soldering of components

This is the Technics integrated amplifier "SU-7700Ⅱ".
It's a late 70s model, just before Matsushita Technics transitioned to New Class A.
After this model, the circuits shifted to using power IC components, marking a transitional period where the sound quality changed significantly. I believe this is the final model in the current mirror series.

The sound tends to be warm and rounded... that's my personal impression.
I feel that recent digital amplifiers (Class D amplifiers) often lack character, but this is an amplifier with a distinctive sound that makes you feel the MOS-FET era.

Regarding the condition, the exterior is in quite good shape.
There's almost no paint peeling on the top panel, and no noticeable major scratches.
(It's nearly 50 years old, so of course there are some minor scratches and corrosion)
It was used and stored in a low-dust environment, and the interior is also clean.

Regarding audio output, the PHONO operation is unconfirmed.
This is because I currently use a digital setup and do not own a record player.
Therefore, I cannot guarantee the PHONO connection.
Also, the subsonic filter operation is also unknown.

Other AUX and TUNER inputs work without any problems.
Both MAIN and REMOTE outputs are also OK.

The volume and tone controls are currently free of crackling.
The switches may have poor contact.
Especially the LOUDNESS switch, sometimes the right channel remains ON even when OFF.
Also, the SP selector has delicate contact, and occasionally only one side will output sound.
Both issues are resolved after 2 or 3 attempts.
(The switches have not been cleaned, so it might be better to clean them)

I will check other operations if you leave a comment.

Output: 60W x 2 (8Ω)
Damping factor: 60 (8Ω)
Impedance: 4-16Ω
Dimensions (approx.): Width 41 x Height 14.2 x Depth 34 cm
Weight: Approx. 8.5 kg