Macintosh Quadra

Quadra was the name used by Apple Computer for most of its Macintosh computers built around the Motorola 68040 CPU. The first of these were the Quadra 700 and 900, both introduced in 1991 with a CPU speed of 50MHz. The former was a compact model using the same case as the Macintosh IIci, with a PDS expansion slot, while the latter was a larger case from the Macintosh IIfx with six NuBus expansion slots.

The latter was replaced the following year with the Quadra 950, with a CPU speed of 66MHz. The line was joined by a number of "800-series" machines in a new mid-sized case, starting with the Quadra 800, and the "600-series" pizza-box desktop cases with the Quadra 610.

In 1991 the Quadra AV series was released, consisting of the 800-series Quadra 840av and the 600-series Quadra 660av, at 80MHz and 50MHz respectively. Both included a Motorola 56000-series DSP and a large new connector on the back to interact with it for audio and video processing. The AV models also introduced speech software known as Macintalk Pro and allowed the computer to be controlled through the microphone. However all of these features were poorly supported in software, and the two AV machines were the only ones to ever use the 56000.

The Quadra name was also used for the successors to the Centris models that briefly existed during 1993. Centris was a "mid-range" series of systems between the Quadra on the high end and the LC on the low end, but it was later decided that there were too many product lines and the name was dropped. Just to add to the confusion, several machines of this era were also called Performa

The last use of the name appeared to be for the Quadra 630, which was a variation on the LC 630 using a "full" 68040 instead of the LC's 680LC40, and introduced together with it in 1994. The 630 was the first Mac to move to the IDE based drive bus, whereas all earlier machines had used SCSI.