This is a continuation of my previous blog post. I will try to share my experience through the design process of this RIAA stage through these individual posts with an attempt to spark some interest in others and in return to get some valuable input from the experience and knowledge of others. Hope this works!

Here is the initial design version for analysis. I’m working through this step by step and refining the circuit in every iteration. The initial circuit is very simple. The first stage is key. We want to achieve as much amplification as possible from this stage before we hit the LCR network. The choice of the 6S17K-V valve may appear as a surprise to the ones not familiarised with this valve.  Here are some notes from Wavebourn around this valve: