If you're looking for a super-versatile Ibanez Tube screamer that can be useful in a wide variety of genres, it's tough to beat the Keeley-modified Ibanez TS9DX Flexi 4x2.
Effects pedal maestro Robert Keeley has made a name for himself for not only his Keeley-branded pedals (the Keeley compressor is legendary), but for his high quality pedal modifications, especially to Boss and Ibanez pedals. Given the popularity and influence of the legendary Ibanez Tube Screamer, it's no surprise that Keeley offers quality modifications to all current shipping Ibanez pedals.
Two of his most popular modification are the TS9 "Baked Mod" and the TS9 "Mod Plus." The "Baked Mod," as its name suggests, offers substantial gain modificatios to a stock TS9 (nearly three times the gain) while the "Mod Plus" offers a qualitative change in the TS9 itself, with a fullter TS808 tone, particularly in the bass frequences. The Keeley TS9DX Flexi 4x2 combines both mods in a single pedal, complete with true bypass. The pedal is named the 4x2 because the 4-way rotary switch combined with the toggle switch offers users 8 total sounds. Not bad for a single pedal.
If used with a clean amp (I tested it with a Carr Rambler), the pedal can be the ultimate blues pedal. With a higher gain amp (I used a Dr. Z Route 66), the pedal can push an already overdriven tone into more harmonically rich overdrive with gobs of sustain. If you're looking for a super-versatile Ibanez Tube screamer that can be useful in a wide variety of genres, it's tough to beat the Keeley-modified Ibanez TS9DX Flexi 4x2. Keeley's modifications take a good pedal and make it more flexible and road-worthy.