Finding out about vintage technology brings me back happy memories, especially learning about unusual technology such as the DCC 18-bit player! The way I see it, digital sound is great but nothing beats the full analog sound wave recording of a reel to reel tape machine or a jukebox vinyl player. It's a shame how so many bits of old technology have been forgotten about, but it's good to know that there are people out there who are trying to revive the good old days of classic technology by infusing it with modern tech (see. mechanical typewriter connecting to the internet).

With that being said, I leave you now with five bits of old technology you may or may not have heard before or even knew existed:

Philips Digital Compact Cassette (DCC)
Launched in the early 1990's, right about the same time Sony launched their mini-disc, the DCC is very similar in size to a regular compact cassette though the DCC had a much sleeker design with the tape itself sliding out of the top and the metal slider protector covering the sprocket holes of the cassette.
The DCC 18-bit player was able to play regular compact cassettes also, though new recordings could only be made into blank DCC's as they wouldn't record into the regular audio cassettes. The Digital Compact Cassette system recorded audio in the early variant of MP3, the MP1 format. The Digital Compact Cassette was somewhat of a miss and hit, though there are pre-recorded albums available in the DCC audio format that you can get unused (even shrink-wrapped!). It's worth mentioning also that Phillips released a portable version of the DCC 18-bit player recorder, which was much chunkier in size than Sony's mini-disc. With that said, the sound quality of a Digital Compact Cassette was actually very good.

8 Track Tape Cartridge
The 8 Track tape is another audio format that was short-lived, and perhaps that was because of its size and inconveniences like having to hit a button to change tracks! The 8 track tape slightly smaller than a cigar box, runs at 3.5 inches per second (IPS) and uses a regular 4-channel quarter-inch tape with each channel divided into 2-channels, hence 8 track. Inside an 8 track cartridge, the tape is on a reel which could hold almost 12 minutes.
The tape is pulled from the center of the reel and moves clockwise around a plastic roller, a foam pressure pad and pinch roller before going back on the outside of the reel again. This meant you couldn't rewind 8 track tapes, though you could fast-forward them. The playing mechanism of an 8 track tape machine works by having the playback head move right into the cartridge and pushing the tape right against the foam pressure pad. To change tracks, you press the selector button which then moves the playback head down into the individual channels/tracks. When it comes to buying 8 track tape cartridges, there are plenty of them around.

What was also somewhat inconvenient about the 8 track tape is how album tracks had to be split up. Because of the loop inside the tape and different album track lengths, the album tracks had to be rearranged differently to fit on an 8 track tape. There were several 8 track players made such as the Wien 8TD4 and Wien 8TD3, JVC Nivico, Pioneer HR-99 and Shibuya 66. You can also pick up quite cheaply recordable 8 track cartridges as well as a cassette adapter for your 8 track player to play regular compact cassette tapes.

Sony Elcaset
Next up is the Sony Elcaset and record player which came out in the mid 1970's during the golden era of the audio cassette and the reel to reel machine. The idea behind the Elcaset was to essentially get the excellent quarter-inch reel to reel tape sound inside a handy compact cassette. Because of its peculiar size, the Elcaset resembles very much a hybrid between an audio cassette and a video cassette. The Sony Elcaset player itself was very much similar in size to a Pioneer SX 3600 receiver.
The Sony Elcaset tape is much thinner and fragile and has a similar formulation to video cassette tape. The Elcaset runs at twice the speed of a compact cassette (at 3.5 inches per second) and works slightly different as the tape gets pulled out into the machine by a single capstan, whereas with a compact cassette the tape gets pushed against the cassette itself. Also, with the Elcaset the tape comes out of the top of it. It's a shame the Sony Elcaset never took of because the Elcaset sound quality is quite impressive! As far as I know, no pre-recorded albums were recorded using the Elcaset format.

Sony D-88 Mini CD 
The Sony Mini CD and pocket D-88 Discman player both came out in 1988 taking the music world by storm. The D-88 player itself was smaller than a regular 5-inch (12 cm) CD, while the CD itself was 3-inch (8 cm). The Sony D-88 came with a battery pack though it could be plugged into mains too. The appealing thing about the Sony D-88 is that not only it was the smallest Discman ever made but it could also play both mini CDs (8cm) and 12 cm CDs.
If you've owned a Sony D-88 or seen one playing 12 cm CDs, the 12 cm CD quite literary sticks out from the side of the player while the exposed CD would spin at 480 revolutions per minute (RPM). The Sony D-88 was definitely groundbreaking and Sony followed up the trend of unusual music players with the Sony WM-10 Walkman and Sony PS-Q7.

VHS PCM adaptor
Before DAT machines (like the Tascam 238) and CD burners came along in the late 1990's, we had Pulse Code Modulation (PCM) adaptors which plugged into a conventional VHS recorder to record CD quality digital audio on a plain simple VHS (or Betamax) tape. You could record up to 8 hours of pure CD quality audio on a single VHS tape, which at the time was very cheap to buy compared to buying a very expensive Digital Audio Tape (DAT) magnetic tape.
The DAT recorder actually does have a very good sound to it and professional recording studios in the late 1980s and early 1990s had always one of these DAT machines. A 3-hour DAT tape recording 32 kHz at 12 bits could hold 6 hours of recording. At the time, Sony was the main player (no pun intended!) in the PCM adaptor game with the PCM-F1 adaptor, which connected to the SL-F1 or the SL-2000 Portable Betamax videocassette recorders. The VHS PCM adaptor faded into the halls of history as it wasn't a very portable solution, but even today seeing one of these upclose brings me back happy memories!