Looking to set up separate circuits for my system

This was a significant upgrade when I did it, I expect you will find the effort and expense worth it. 

I'm not very savvy with this electrical stuff; is there any way to achieve any of this without tearing up the walls? 

@kjl1065  Paul McGowan is correct, you can combine everything except the amplifier and run these from a good power conditioner with isolated outlets. There are various ways to spend a fortune here, but it’s unnecessary. A conditioner by a reputable brand, like this Panamax unit, provides five electrically isolated banks of outlets with effective noise suppression and automatic voltage protection. In addition to providing clean power and active protection for your expensive gear, it prevents noise produced internally by one component from affecting the others.

Ideally, your Bryston 4B3 Cubed amplifier should have its own 20A "home run" circuit, meaning it is wired directly to the panel with no other outlets on it. Romex 10/2 (10 AWG) is rated for 30A and will do the job. Hospital grade 20A outlets like this one employ higher conductivity, heavier gauge contacts with increased pressure as compared to standard residential outlets, or you can spend big on Furutech, etc. You will want to make your electrician aware that this circuit should be wired in the panel such that it is on the same 120V leg (phase) as the outlet with power conditioner that powers your source and preamp components. This provides all of your audio components with a common ground reference and minimizes noise. 

Following these simple steps will give you what you need without having take out a second mortgage.

Yes - did this two yrs ago, some of the best money spent on my system...everything in my audio room improved instantly & is better for it. Cost was less than new power cables and he did not have to tear into walls in my situation....depends on the run from panel to your room. I had an electrician do it - if there was every an issue it was done by a pro. Total cost for all was $2100 including the new Furutech outlets, an updated electrical panel, the runs to the audio room, and the labor.

I used the same guide mentioned above as a go by for the electrician (Dedicated AC power lines and wall power improvements for audio By Vince Galbo 2024).  Two separate 10 AWG high-grade twisted copper...something about the twist = I am not an electrician, and upgraded the connections in the panel and also the Furutect outlets in my room. 

From what I understand -  The key is not about the current but reducing resistance. I have my amp plugged in directly to one and the rest of my system to the other via a Synergistic Research Powell Cell which I already owned.

I was concerned about lighting strikes & ground current effects...in the ten yrs I have lived in my area/county - three homes hit by lighting. One was a direct hit = looked like a bomb went off...total destruction/fire. The other two were not direct hits but most electrical systems in the homes destroyed by ground current. Discussion with the master electrician that did the work for me = he indicated no surge protection of any kind/format/expense will protect your house/electrical grid from 1 million volts. Also discussed about using a dipole system on both sides to my property as a deterrent....he indicated he would never recommend drawing lightening towards your home. Every time a significant storm comes thru I disconnect everything coming into the room, even ethernet. 

Again - money well spent!
 

Two 12awg Romex wires into two 15amp circuit breakers and 

two hospital grade duplex outlets provide power

to monoblock amps (one circuit) and front end via 

Chang power strip (second circuit). Underground power

in our community helps with RFI but HVACs still pull on the grid until 

10 pm or so. A wall wart voltmeter is fun and can help 

you predict your power quality for the listening session.

Dedicated wiring is, as others have discussed, very beneficial. I have five duplex outlets, three on house circuits and the aforementioned two 

that are dedicated.