Heritage Audio HA73JR2 - British-Spec 500-Series Preamplifier and DIReal deal 73 sound. The 73JR II is an update to the already classic 73JR a true 73 style mic preamp in a single 500 series slot, with some added features that will satisfy the most demanding of recording engineers. Employing discrete circuitry and conventional components, the 73JR II is a faithful 3 stage all Class A 73 preamp. Styroflex and tantalum capacitors have been used throughout. No corners were cut. The all discrete Class A hi pass filter is