Sony always made excellent equipment but by the 1970s it truly excelled and started to produce really first-class products. Its domestic equipment verged on professional grade and after it entered the professional arena its equipment was second to none, for example its professional DAT and 1" videotape recorders were used by broadcast stations across the world because they were state-of-the-art and their quality was excellent (so too was their serviceability).

I still own quite a number of Sony devices but I'd like to specifically mention my Captain 55/ICF-5500M AM/FM/SW receiver, my two ICF-2010† and a ICF-2001D† AM/FM/SW receivers and my 100W per channel stereo amplifiers from that era and they all still work perfectly.

What's remarkable about these devices is that their build quality is excellent, in fact they've essentially been fault-free and not needed any maintenance for 50 years despite being in regular operation since I purchased them.

Of particular note is that none of the potentiometers (volume pots, etc.) has gone noisy/scratchy over this time which is quite a remarkable achievement really. Likewise, I've not had to replace any electrolytic capacitors either. (Incidentally, the pots that Sony used in their equipment around that era use a composite conductive plastic that has remarkably good durability—ipso facto my ones are still 'scratch-free'.)

When I bought these devices I had no difficulty in obtaining service manuals for them from Sony's service department for a nominal cost. Unlike these days, the service manuals are excellent and they come complete with comprehensive circuit diagrams. The circuit diagrams for the radios are printed in two colors—important info is overprinted on the black circuit diagram. I still have those manuals despite never having had need to use them because the equipment is so reliable. (When it comes to servicing equipment young people these days haven't a clue how much better manufacturers treated owners back then.)

BTW, whilst both receiver models have excellent performance, the ICF-2001D is exceptional. For a domestic appliance its performance specifications were close to or on par with many communication receivers of their day. It has a FET RF stage with excellent crossmodulation figures on all bands and good IF bandwidth skirts for adjacent channel interference rejection. In fact, some shortwave hackers and AR operators considered the radio so good that they replaced the original IF filter with a proper mechanical filter which definitely put the receiver into the professional class. Another very unusual feature was that the receiver also has an excellent synchronous detector which works remarkably well—if one has interference on say one sideband of an AM signal then one just switchs the sync detector to the other and the interference disappears.

Tragically, Sony is no longer the company that it once was. Gone have most of the high-tech consumer products, gone have comprehensive service manuals, and so on. After Sony's founders Masaru Ibuka and Akio Morita died in the late 1990s the company completely changed direction. It greatly reduced tech manufacturing and development and bought into the US media/movie business. Many owners of this older Sony equipment would now argue that the highly engineering minded founders if still alive would never have allowed this change in direction.

For many, myself included, Sony is now perceived as nothing more than a pariah company with nothing other than profits in mind—profits made on the end of DRM (remember the Sony virus?).

Great shame that once great tech company is no more.

†https://www.cryptomuseum.com/spy/icf2001d/index.htm

https://radiojayallen.com/sony-icf-2010-an-all-time-classic/

Edit: on that first link there's mention of Sony's smaller ICF-7600D. I also used have this receiver too but only the 'D' version. It was a good receiver but didn't quite have the performance of its bigger brother. I used it whenever I was traveling internationally. It was a great companion when in countries where I couldn't speak the language and wanted news.