The Univox UEQ-1 is a unique effects processor, consisting of a real spring reverb and a seven band graphic equalizer. I believe that this was originally made for acoustic instruments, but I've only used it with an electric guitar and it's definitely more than suitable for any instrument that you'd like to use with it. On the side of the unit, it's got 1/4" connections for both hi and lo input, for hi/lo output, with a switch to choose between the two, and also a jack for a footswitch to engage or bypass the reverb. It has a built in power cord and isn't rack mountable as it sits in it's own casing that looks like a guitar amp head.
The configuration of the Univox UEQ-1 isn't too difficult to follow. The seven band graphic equalizer is straight forward enough, covering frequencies between 100 Hz and 7 kHz. It's got a dB range of 12 either way. The reverb section is also pretty easy to understand, with parameters for depth, tone, and volume, as well as a switch for turning the reverb on, which can also be done with an optional foot switch. I haven't seen the manual for the UEQ-1, nor do I think one would be necessary.
While I haven't used the graphic equalizer much on this, the reverb on the Univox UEQ-1 is awesome. I've only used it with electric guitar, but it sounds great for getting some spring reverb in place of the reverb you'd find on your amp. It's more than an effective reverb, as it's definitely comparable to a high quality spring reverb found on an amp. Even if you do have built in spring reverb on your amp, this has it's own color and brings it's own thing to the table...
The only Univox UEQ-1 that I've seen is the one that we have at the studio that I work at. It's from the 1970's, although I don't know how many of them were made since they seem rather rare. I don't really know how easy it would be to find one of these, but if you could find one at a reasonable price it would more times than not be worth it. The Univox UEQ-1 a nice asset to have around any studio.