How to modify audio Heathkit Comanche tube Ham band receiver by D-Lab

This is a nice vintage receiver, but the audio was pretty bad, pinched up, kind of like a scratchy Apache. I took a look at the schematic and discovered a few simple improvements for better low end response. The video demo clearly shows a nice improvement. Cost is under a dollar and can be completed in about 30 minutes. These receivers are getting hard to find in operational condition. Hope you enjoy the Hammered ham!