Environment And Rendering
All the light sources I used are simple plane objects with a Maxwell Material emitter. I used the Highlight tool in max to make a nice reflected light source in a specific place on the object.
I applied a noise modifier to subdivide the wall so that it didn't look too flat (Fig32, Fig33, Fig34 and Fig35).
As you can see, the main image (guitar with an amplifier) doesn't make it possible to see all the details. So I decided to make additional renders, but in a different environment - such as a studio (Fig36 and Fig37).
As this image shows, there aren't any specific settings. Everything is extremely simple (Fig38).

Fig. 38
The most important thing is the camera settings, because the camera in Maxwell is similar to a real camera (Fig39).

Fig. 39
Some Tips
Closed rooms increases render time due to the many reflections of rays of light. Exterior renders are much faster, so let the light rays flow out from scene.
Naturally, many light sources increase the render time too.
Multilight features increase memory usage. To get around this, I make one separate material for each light source and then I make a test render with Multilight, adjusting the light's intensity and remembering the value. Finally, I edit the value in the material according to Multilight in the render. For example, 200 units in Multilight for 50 watt light would correspond to a 100 watt light. Now you can disable Multilight in render properties, have the same result and save memory.
Here you can see some of the render tests (Fig40, Fig41 and Fig42)

Fig. 40