The Keeley BOSS BD-2 Blues Driver
Phat Mod

A Pro-Quality Overdrive Pedal Mod review
by Philip Snyder

A few weeks ago a student of mine picked up a Boss BD-2 Blues Driver pedal at the local chain music store.  I had heard a little about these pedals but hadn't thought much about them... just another Boss overdrive in a different color. Amazingly enough, when I plugged in and played through it there was a significant difference between this pedal and the other overdrives that Boss has offered over the years. This one seemed to react more like a tube amp to the dynamics of my playing. Very organic and very interesting...

Since I had been so impressed with the Keeley Compressor I decided to look into Rob's mod of the Blues Driver. Rob had also been impressed with the pedal and had a few ideas on how to improve what was already a good piece of gear. First off, he went through it and replaced all the cheaply made components with hi-fi ones. Ceramic capacitors were removed in favor of silver mica and tantalum ones. The stock resistors were replaced as well. This boosts the quality of the signal and cuts down on noise... a common upgrade for Rob to perform. The pedal is amazingly transparent for an overdrive and re-building it with high-quality caps and resistors only enhances this.

The next (and possibly the most important for 12-string bassists) thing he does is to add his "Phat" mod which is controlled with a mini-toggle switch. With the switch in the "off" position the pedal acts as a high-quality version of the original. With the switch in the "on" position you get added low-end response. Thus the name "Phat" mod. This is exactly what most overdrives lack and what a 12 needs the most. This feature helps to bring those fundamentals up to the level of the ever-ringing octaves!

The overdrive that the Blues Driver offers is somewhat "grittier" than that of the ultra-smooth Ibanez TS-9 Tube Screamer. I have a Keeley modded TS-9 and I love it... for guitar, but I couldn't get what I needed from it for the 12-string bass. The problem with the TS-9 is that it suppresses the low-end in favor of a mid-range hump, which is obviously bad for bass. The Blues Driver in the Phat mode boosts the lows and helps the bass strings to compete with the octave strings. Let's face it, those octaves can be overwhelming at times and sometimes the fundamentals need a little help. This is not like compression, the pedal is actually boosting the lows. 

The Blues Driver has three controls along with the Phat switch; Level, Tone, and Gain. The Tone control is still very effective when the Phat mode is on. Within just a few minutes I was able to dial in a reasonable facsimile of Tom Petersson's live sound and then by adding a little more gain and rolling back on the tone a touch I got a pretty good Doug Pinnick as well. Not bad at all for a pedal!