Preamp modification for a 1967 RCA solid state record player

Here's a video, from Jordan Pier, that inspired me to do this video:    • Preamp modification for Rca 1-emp-2l   In the past, I've ran into many single tube record players that use a 3V crystal cartridge to directly drive the output tube of the record. Unfortunately, most of these cartridges are dead by now. It's also unfortunate that new 3V cartridges are no longer made and NOS ones are often expensive and suffer from age related issues. Of course, one can install a current production 1/2 V ceramic cartridge and the record player will work; but, there won't be much volume. In the tube units, I get around this by installing an additional triode vacuum tube (something such as a 6AV6, etc.) as a preamp stage. This will boost the output of a 1/2 V ceramic cartridge to a higher level that will properly drive the output tube and give better sound quality. The 3V crystal cartridge lasted well into the solid state record player era and it was not uncommon to see kiddie record players from the mid '70's that use a 3V cartridge. In such a case, what do you do as far as a preamp stage? In this case, we go with a German-built preamp module that cost about $10. Once it's properly installed, it should work fairly well for boosting the weak output of a modern cartridge to a level that the original phonograph amp is comfortable with. If you're working on a stereo record player with a 3V crystal cartridge, you'll need two of these preamp modules (one for each channel). I don't look for 3V crystal cartridges to ever be made and the supply of NOS ones is certainly not going to increase; so, if we're going to keep these old record players alive, it will be necessary to make certain modifications to them.