MXR Custom Shop CSP099 Phase 99

  • By Ian Garrett @tonereport
  • January 09, 2014

The MXR Phase 90 is one of those classic pedals everyone should own, or at least try out. Recordings from Pink Floyd to Van Halen and countless more have been made using the Phase 90.  MXR has made several versions of the pedal over the years, with older versions commanding a high price in the used market.


The new Phase 99 from MXR’s Custom Shop is the latest version of the Phase 90. The 99 comes in the same size enclosure and features not one, but two separate Phase 90 circuits. Pick a speed, slow or fast, or have one cascade into the other. In addition, you get the choice between regular or “vintage” Phase 90 tones with the flip of a small toggle button.   Another toggle lets you choose between parallel or series – with its own corresponding LED.



Phase is one of my favorite modulation effects, and I generally prefer it before my dirt pedals. But it can work well after dirt as well – try both, there’s no right or wrong way just what works best for your rig. The Phase 99 has all of the tone of the original Phase 90, only it gives you two speeds from which to choose. For a different twist, it offers two outputs. Run the second output to a second amp in stereo, and use the two different speeds for a wide, spatial effect.   


If you don’t run two separate amps but want to have both phase circuits engaged at the same time, an internal switch makes this possible. Then use the sync button situated between the two speed knobs to toggle through speed 1, speed 2 or both.



With two speeds to choose from, I found the sync button awkward to use. I’d prefer a second stomp switch instead, to allow a user to change speeds on the fly.  In order to keep the Phase 99 to its compact dimensions, as well as to keep costs in check, this likely wasn’t a realistic option. 


TONE:  4 out of 5 STARS

I’m a big fan of the classic Phase 90 tone.  At slower speeds, it adds a nice mellow effect, and it has a really haunting sound when used with some added reverb and delay. At faster speeds it adds some chewy grind, and in a pinch it can be used to create a vibe effect, or even a faux-Leslie simulator.  Having the vintage mode is a nice option, too; the effect is more subtle, making it more useful for some. 



Unlike other Phase 90 pedals I’ve owned in the past, there’s a nice sparkling effect to the orange paint job of the Phase 99, making it appear a little higher end.   The rest of the pedal is solid MXR construction, running on either a 9v battery or an external 9v power supply and true bypass.


VALUE:  3 out of 5 STARS

If you don’t already have a Phase 90 pedal, but wished you had the option to choose between two speeds in one box, then the Phase 99 might be right up your alley.   Otherwise, I’m not convinced this is an option that has been frequently requested.  Also, having two smaller speed knobs in close proximity to one another means you can’t change speeds with your feet like on the basic Phase 90.  In some ways, I find this pedal a bit limiting.  With that being said, if you run stereo amps (and I do), there’s no denying two phase circuits running at different speeds simultaneously is a pretty cool effect.



The Phase 99 Is a worthy update to the venerable Phase 90. If you’re looking for a little more versatility in your phaser but still want that classic tone MXR is known for, this should be on your short list.

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  1. george

    Hi folks !!!!!!  I like all your devices !!!  TNX !!!!!!!!!!!!!!!!!!!!!!!!!!!!