I believe common sense is an asset when it comes to this topic. The best solution to filtering or regenerating a garbage ac line is to eliminate it from the equation. I have an ASR amplifier that runs off two power supplies and a battery. The battery has installed, six lead acid gel rechargeable batteries. The two power supplies, recharge the battery and that’s how the power amp gets its juice. My system sounds clean and my other components are just plugged into a passive PS audio line filter. There are other high fidelity amplifier manufacturers who are offering battery power to their flagship products. And that’s because the solution is so simple.