The make up of the Ibanez LF-7 Lo-Fi is generally quite easy to understand as the parameters are straight forward and there isn't anything too out of the ordinary here. The pedal has knobs for drive, lo cut, hi cut, level, and mode, which can be put on either guitar, drums, or mic. As you can probably tell just by looking at it, everything is pretty self explanatory and I don't believe that manual is needed for this reason.
The Ibanez LF-7 Lo-Fi pedal is really just a glorified EQ pedal with some other helpful parameters. It cuts out certain frequencies which give it that 'lo-fi' type of sound. You do have control over these frequencies to a degree with the hi and lo cut parameters. As I mentioned before, I've only used the pedal with electric guitar, but judging by the available modes, the pedal is able to adapt to a few different applications. I do like 'lo-fing' my sound as much as the next guy, but I really don't feel like I need to have this pedal around to achieve this sort of sound.
The Ibanez LF-7 Lo-Fi is a discontinued pedal as far as I know, but they are easily found if you want to get one used. I don't believe that this is a necessary pedal in any situation, but it does make it easy to get some lo-fi effects in a hurry. I think that I can get some pretty similar sounds by simply using the EQ on my amp or guitar, but this does provide more versatility for sure, and at a very cheap and reasonably priced. If you think you might be interested in a pedal of this nature, I'd recommend checking it out as you don't have too much to lose even if you buy it and decide it isn't for you.