Initially sold for ¥49,800
Budget version of the SPX90 in a table-top form. Music Technology introduced it by writing "The latest signal processor from Yamaha may be aimed primarily at guitarists but the small studio owner might prefer to look at it as an adaptation of the SPX90." In facts, while removing the sampling features found on the SPX90 and the ability to use a remote, the REX50 introduces a stereo input and a few distortion effects.
Even if the amount of controls seems very restricted, only 8 very mushy buttons, programmability is very detailed given it was a very cheap unit. Every effect can be customized, and changes can be saved to memory to be recalled later. Very good delays, usable distortions.
The overall aspect and the fact that is a very basic plastic box built around a PCB is reminiscent of the Sinclair ZX80. Yet it's larger than you'd expect and the weird shape makes it hard to stack it with anything else. Considering the quickly rising prices on the used market of SPX90 racks, the REX50 could be a great alternative.