Do I need a power conditioner?

... My audio system when all equipment is playing can surge up to 18 Amps ...

As far as the components. ALL R FUSED.

I don’t doubt that your system can draw 18A. Typically, a system such as that is best served by using multiple dedicated AC lines.

The fuses in your components are there to protect the component, not the AC line. Similarly, the breaker in your service panel is there to protect the AC line, not your components. If you’re using a 30A breaker on a line designed for 20A service - and that uses a 20A receptacle - that’s a clear violation of code. And it’s a potential fire hazard.

Use of ALL CAPS is considered shouting, btw.

Once, early on I had a rig set up for getting high quality CDR's from LP's. I had no power filters of any kind. When playing back the CDR, there was noise in the sound field of the CDR. I could almost hear a faint radio station. I had a "noise sniffer" and it confirmed a very noisy AC line. I bought a Monster Power conditioner. I put it in the chain and did the dub again. On playback, the noise was gone.

  Another scenario; I had an Adcom power amp (GF5800, I think). Everytime I powered it up in the winter, the tiny amount of static that I discharged on my audio rack, would cause my Adcoms' overload light to come on. It would go back out BUT I didn't want this happening. I bought a PS Audio power filter. After putting it in the chain, the issue with the Adcom was gone! The results don't always have to have a very audible benefit to justify having one. Cheers. Joe