Phil Jones Session 77 100w Bass Combo For 13 years Phil Jones Bass has been building bass amplifiers for the most demanding bassists. This time he looks into the most cost effective way to build an amp without sacrificing the most important aspect: TONE! The Session 77 is loud enough to work with most drummers and compact enough to be carried around. The two super high-efficiency and proprietary 7-inch speakers were designed by Phil Jones to get the most of the 100 watts class D amplifier. These two proprietary woofers are complimented by a high energy 2-inch K high frequency transducer.