In my first year of uni, I bought my first effects pedal. For reasons now lost in the mists of time, and possibly the mists of (ahem) something more intoxicating, I chose to buy a phaser. It was a Ken Multi MPH-7, purchasable at Maplins for about thirty beer tokens.
It was by any discerning standards a terrible pedal. Made of cheap grey plastic, it was so far from the "true bypass" beloved of FX geeks nowadays that it had a noticeable effect on the sound of guitar even when switched off. Fortuitously though, it somehow sweetened the sound, on or off, and although capable of some fairly extreme sounds, worked best on more subtle settings. It was a great sounding thing.
I lost the Ken Multi a long time ago but I've been meaning to get another phaser for a while. Given what I liked last time perhaps I shouldn't have been quite so snobby, but this time I thought I would get a "proper" pedal rather than some no-name brand, so I was looking at brands like Electro Harmonix, Carl Martin and MXR. I tried a few out but in the shop it was a toss up between the EHX Small Stone and the MXR Phase 90. Eventually I couldn't resist the stronger sound and classic bright orange case of the Phase 90. Amazingly it cost about the same, in real terms, as that cheap Maplins phaser did all those years ago - and this is a US made pedal with a metal case and quality parts.
Unfortunately, once I got it home and tried it with my guitar and amp, I found that it wasn't quite as I had thought. It always distorts - even on a very clean tone. It's not just my gear either; there is lots of discussion on the net about this and there is even a well-recognised "R28" mod that involves cutting a specific resistor out of the circuit and supposedly goes some way to curing this. (I might try this if I can get up the confidence to wire it up to a switch rather than just removing it).
Luckily, where this does work is on overdriven and distorted sounds. Yes, the mid-range push is still there, but now it adds to the sound by making it just that little bit rougher, more distorted. It's very similar to the mild distortion added by a wah-wah, which also works well on crunchy sounds - in fact, it often sounds like an auto-wah, particularly on lead lines, changing the overtones and harmonies as you play. This is unquestionably where I would use it most and from this point of view it's a worthwhile addition.
Given the similarity in tonality, I was curious to find out what the combination of the Phase 90 and my old Cry Baby (a late 70s Jen Super with a white Fasel) would sound like. Turns out - terrible. These two pedals don't play nicely together at all. The similar mid-range boost from both pedals combines to produce an overly harsh, gratingly distorted sound. It might be useful occasionally for certain deliberately unpleasant sounds but I don't tend to go for those.
Lessons: I wish I'd read up about the Phase 90 more before I bought it. The shop try-out wasn't representative enough, but I should trust my ears more because I did catch a bit of these symptoms when I was trying it out. I should have tried more variants (e.g. the "script logo" version). But still, I'm happy with it for now, although I will probably try removing that resistor at some point.