Blues had a resurgence in the early 1990s with the likes of Gary Moore and Eric Clapton having big hits with their blues albums. Boss realized the need for a pedal that could produce a bluesy vintage tube amp tone and in 1995 they came up with the Blues Driver. The BD-2 was been a success from it first went on sale and it's still one of the best selling Boss pedals today. One of the pedals main features is that the level of distortion is proportional to the picking strength.