The GML 9500 is a two band parametric equalizer in the form of a rack mountable piece of gear that will take up three rack spaces. It has XLR connections in the back and is an all analog, tube based EQ.
If you have any experience with parametric EQs in the past I would say that you shouldn't have too much trouble operating the GML 9500 . It has pretty straightforward parameters and everything is easy to find and use. The unit has two bands - one for low frequency and one for high frequency. Each band has a switch to choose between a number of set frequency bands and then each has a knob for both boost and attenuation. There is also a bandwidth knob that applies to both bands as well as another switch for attenuation selection. I don't have the manual for the GML 9500 but unless you are a beginner you don't really need it.
The sound quality of the GML 9500 is absolutely pristine. These are some of the warmest and cleanest EQs I've ever used and is really what I have come to expect from the GML brand. This being said, I do feel that this EQ is best suited for some things rather than others due to its thick sound that comes from the tubes in this thing. I only use it on a few things because it doesn't always work to add the huge thick sound that this offers to a signal. However, for the things that I do use it for like drums and electric guitars it really works flawlessly.
I've been using the GML 9500 for about two years and it is definitely an EQ that has something special to it that distinguishes itself from the rest of the pack. This EQ is designed for professionals and because of this it has a huge price tag, so unless you are a professional or a home studio with a big budget, its hard to imagine too many home studios having one of these. If you are looking for top notch tone from an EQ, the GML 9500 will give you that and then some...overall, the GML 9500 is just a great piece of gear.