Looking to set up separate circuits for my system

For the cleanest poer signal.

Use an AC to DC to AC converter in the context of audio equipment is most commonly found in High-End Power Regenerators or Double-Conversion Uninterruptible Power Supplies (UPS).
​While a standard power strip or surge protector simply filters the electricity coming from your wall, a regenerator completely rebuilds it to ensure the "purest" possible signal for sensitive audio components.
​How the Process Works
​The conversion process happens in three distinct stages to isolate your gear from the fluctuations of the electrical grid:
​AC to DC (Rectification): The converter takes the alternating current (AC) from your wall outlet—which often contains "noise" from other appliances, voltage spikes, or frequency fluctuations—and converts it into direct current (DC). This stage acts as a gateway, stripping away the messiness of the utility power.
​The DC Reservoir (Storage/Filtering): The power sits momentarily in a DC bus, often supported by large capacitors. This acts as a buffer or a "clean pool" of energy. In a UPS system, this is also where the battery is connected.
​DC to AC (Inversion): An internal electronic oscillator and inverter take that clean DC and turn it back into 120V or 230V AC. Because this AC is generated locally by the device’s own internal clock, it is a perfect, steady sine wave at exactly 60Hz (or 50Hz), regardless of what is happening at the wall outlet.
​Why It Is Used in Audio
​Audiophiles and studio engineers use this technology for several key reasons:
​Eliminating Electromagnetic Interference (EMI): The "AC-DC-AC" path creates a physical break from the grid. This prevents clicks, pops, or hums caused by refrigerators, dimmers, or computers on the same circuit from reaching your speakers.
​Voltage Stabilization: Audio amplifiers perform best when they have a consistent voltage. If your house voltage drops (brownouts), the regenerator uses its internal reservoir to keep the output rock-steady.
​Total Harmonic Distortion (THD) Reduction: Utility power often has a "clipped" or distorted wave shape. Regenerators output a near-perfect mathematical sine wave, which can reduce the heat and noise generated by the transformers inside your amplifiers.
​Common Examples
​Power Regenerators: Devices like the PS Audio DirectStream Power Plant series are dedicated specifically to this task for high-fidelity home audio.
​Double-Conversion (Online) UPS: Units from brands like Eaton or APC (specifically their "Online" or "Double Conversion" models) use this topography to provide laboratory-grade power and battery backup.

I recently had an electrician install a 20a, dedicated Isolated Ground circuit to power my system. It powers my McIntosh MPC1500 power controller which powers my entire electronics rack. It was a pretty simple install as my listening space is the basement man cave and is a straight run from the electrical panel to the wall separating the finished area from the unfinished area. He did it for $150 which included the cost of the parts. Wire, breaker, and hospital grade outlet. 
 

I didn’t have any noticeable issues with the power source before, and I can’t really hear any improvement after. But for $150, I figured why not?  

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.