I wouldn't know for definite but I doubt it was a Mesa during the early 90s as he favoured Marshall before moving on to Fender shortly afterwards. Unfortunately there is very little information available as to what gear Richie actually used/uses which proves extremely frustrating when it comes to reproducing his various sounds - any hints on Dry County solo effects would be welcome! So much gain and feedback and yet such sweet sounding high notes without ear-piercing treble - great sound!