Emulation

SynthBuilder runs on either 68k or x86 processors running the NeXTSTEP operating system. Previous is an open source NeXT Computer emulator which emulates the 25MHz 68040 processor and a DSP [3]. Installing the NeXTSTEP operating system requires several steps involving multiple floppy disk and CD images. However, the hard drive image containing the entire system is compressible to about 60 MB, and easily downloadable from the internet [4]. The SynthBuilder application is archived at NeXTComputers.org [5]. The Piano patch is part of the Sondius example collection, available from the CCRMA website [6].

The Piano patch has three different configurations. This makes it portable between NeXT computers with a single DSP, non-NeXT computers with a single DSP, or a Frankenstein box with 8 DSPs. The last configuration offers 3 voices for regular notes and one for high notes beginning at E7. The high notes are modeled using modal synthesis. The NeXTcube is only capable of one voice and uses the regular model for all notes. Unfortunately, the emulator is also limited to one DSP, so the Frank configuration cannot be allocated in its entirety. If I remove the regular note synthesis subpathes, I can then hear the high notes modal synthesis. There in no MIDI support in the emulator and all MIDI input elements must also be removed. The emulation of the 68040 processor results in performance comparable to that of the real hardware which, by today's standards, is quite sluggish. Nonetheless, the Previous emulator offers some key advantages.