These are some of the BIGGEST cassette decks ever made. Were they better than a regular sized deck? In some cases, yes, they were hiding complex mechanical construction and sophisticated electronics to achieve the best possible sound. Let's take a look at the models and the years they were made.
The AKAI GXC-570D was first manufactured in 1975 and it features 3 heads and 3 motors.
The eumig FL-1000 was made in Austria in 1979. This is a highly regarded cassette deck.
The OPTONICA by SHARP RT-6906 from 1981 was a 3 head machine with an extra head for a sophisticated track search system.
The PIONEER CT-A1 from 1979 is a 3 head unit with a complex tape calibration system. Briefly sold as Linear Phase 7000 a company that was recently acquired by PIONEER.
A big and beautiful cassette deck from Norway. This is the TANDBERG TCD 3004 from 1980.
A not so well remembered model is the TEAC A-860 from 1976.
A two-box solution from Technics. This is the RS-9900US from 1977.
Here is something interesting, something you would not expect. This is the 3 head UNITRA MDS-624 from 1983....apparently only a prototype...
Finally, the BIGGEST of them all but never manufactured. The LUXMAN X-3K, only shown as a prototype in 1982. With this system the aim was to completely extract the tape from the cassette and run it on a free and precise tape path.