Yamaha SPX 900 Effects Processor #01215 (Vintage)

Classic late 80s digital effects unit, with 90 dB of dynamic range. From the owner's manual:

"The Yamaha SPX900 is a highly sophisticated digital reverberation and effects system which offers 50 preset effect programs including accurate simulations of natural reverberation and early-reflections, delay and echo effects, gated effects, modulation effects, a versatile compressor, a harmonic exciter, multiple effects which function as several Yamaha SPX900 units in one, freeze (sampling) programs and others.

With a sampling frequency of 44.1 kHz, it delivers full, flat frequency response from 20 Hz to 20 kHz for exceptionally clean, “transparent” effect sound. The preset effect programs can be edited, re-titled, and stored in any of 49 RAM user memory locations. Individual two-band parametric EQ and dynamic filter parameters are provided for each effect program for precise tonal tailoring. In addition to the basic effect and EQ parameters, the Yamaha SPX900 offers a list of “internal parameters” which provide exacting control over the effect sound.

The Yamaha SPX900 is also MIDI compatible, with a MIDI in terminal that allows MIDI selection of effect programs, and a switchable MIDI THRU/OUT terminal. When switched to OUT, edited programs stored in internal RAM can be dumped to a MIDI data recorder or other data storage device. Programs thus stored can be reloaded when necessary via the MIDI in terminal.

As an extra touch of convenience the Yamaha SPX900’s input and output terminals can be switched to match -20 dBm or +4 dBm line levels + providing compatibility with a broader range of sound equipment."