Change a material color in C# Unity 5.

Hi guys , I've got a problem i've been having all day and I'd really just like to get it sorted .
I'll try my best to illustrate , I've maxed out what google can tell me.
Within Unity 5 :
I want to change the color of a material , to the color of another material ,or at random between a list of colors.
I've got a dancefloor that needs to change colors every time a beat is picked up. So far i've got it set up to simply swap between two materials however I want the color of the first material to be different each time the beat is detected.

Whats the best way to set up a materials color change ? Its just a standard material. So far I've tried

objeto.GetComponent<Renderer>().material.color =("_TintColor",( 0.3,0.3,0.7);

Which is no good. Along with
objeto.GetComponent<Renderer>().material.color = Color(Random.Range(0.0,1.0),Random.Range(0.0,1.0),Random.Range(0.0,1.0));

I'm not a great scripter I really just edit values in scripts I pick up off the web but i've gone through about 5 different versions today and can't seem to simply get a materials color to change.

Can supply pictures if needed.

 

There are a lot of ways to do that... (I have not actual tested this code)
What I do are to make a array of the materials to use. If you just change the material on a Renderer with by for example, changing the

Code (csharp):

1. objeto.GetComponent<Renderer>().material.color = ...

then you are actual creating a new material each time, and the garbage collection will be a bit busy.

What I do are to first make a array of the materials and colour I'll be using.

Code (csharp):

1. Material[] myMaterials = new Material[8];

and then assigning materials to the array.

Code (csharp):

1. myMaterials[i] = objeto.GetComponent<Renderer>().material;
2.   myMaterials[i].color = MakeMyColour(i);  // for some reason this makes new materials (no new statement)

then i assign it to the gameobject when needed

Code (csharp):

1. someObject.GetComponent<Renderer>().material = myMaterials[......];

Another thing that if you do:

Code (csharp):

1. myMaterials[nn].color = MakeMyColour(j);

Then you will change all objects with that material at the same time.

P.S. ( you probably know it already...)
And if possible, avoid

Code (csharp):

1. objeto.GetComponent<Renderer>()

in update() on or the other dosent matter much, but to many will slow things down try to use

Code (csharp):

1. private Renderer objetoRenderer;
2.   void Start () {
3.     objetoRenderer = objeto.GetComponent<Renderer>();
4.     .....
5.   }
6.   void Update () {
7.     ....
8.     objetoRenderer.material = myMaterials[......];
9.     ....
10.   }

D.S.