Color Neutrality
By yoruba and crystalcuber
Color Neutrality (CN) is the ability to solve on multiple different cube orientations equally well. For example, a color neutral ZZ solver may be equally comfortable solving any color of EOCross. Color neutrality is very helpful for EOCross, as having more options will allow you to choose a faster and more efficient option.
In this page, we will explain how CN works and how to learn the main options for ZZ method speedsolving.
Definitions
Cube orientation is the angle at which the cube is held, based on the position of the center pieces. For example, scramble orientation is the conventional way to hold the cube during scrambling, with the white center at the top and green center at the front. Usually, cube orientations are described by the top and front centers, and abbreviated like "white top green front".
An EO axis (plural: axes) is a pair of two centers at the Front or Back that determine which edges are good or bad. For example, if a scrambled cube has the orange center at the Front and red center at the Back, that is the orange/red or red/orange axis. From the EO tutorial, we learned that the bad edges may change when holding the cube in different orientations. However, as long as the orange/red centers are both at the Front/Back in any order, the bad edges will actually be the same. In total, there are three EO axes on the cube (red/orange, green/blue, white/yellow).
EOCross is a combination of solving the cross pieces of a certain color, and solving the EO of a certain axis.
Types of CN
Fixed
Fixed means always starting the solve from one specific cube orientation. This gives you only one EO axis and one cross color to work with, so there is only one EOCross option to consider. One might also notice that you can do a y2 to get the same EO and cross, which is true (we will go over this in the practicing article).
The most common choice by beginners, which can also be solid at a high level.
The main advantage for fixed solvers is better piece recognition, due to getting used to a single cross color and EO axis. This can be a great boost to lookahead.
The downside is worse EOCross efficiency because only one EOCross is considered. Later on, this could create problems with planning the first F2L pair.
x2y
x2y is the practice of solving on two opposite cross colors. For example, an x2y solver may choose to solve the white cross or yellow cross. For each cross color, there are two possible EO axes to choose from, giving a total of four distinct EOCross options. For instance, that solver would choose from:
- White cross, green/blue EO axis
- White cross, red/orange EO axis
- Yellow cross, green/blue EO axis
- Yellow cross, red/orange EO axis
x2y is the most popular option amongst top solvers. This allows you to choose significantly better EOCrosses than a fixed solver, while not having to go through the hassle of becoming full CN. It can be considered as a balance between these two options.
x2y EOCrosses at the highest level average about 7-9 moves on average and low 1s in execution.
Full CN
Full CN is the ability to choose any EOCross. This means considering any combination of cross color and EO axis. Contrary to popular belief, full CN is possible in ZZ. In total, there are 12 distinct EOCross options to check.
Full CN is the most efficient option, with solutions ranging from 5-8 moves. Because the EOCross solutions are generally shorter, the first F2L pair is easier to plan. The solutions can also be ergonomic and fast to execute (sub 1 second).
The biggest disadvantage is increased inspection time spent on EOCross. In addition, F2L piece recognition is much harder to master. However, it could be argued that the reward is worth the effort.
Which one to choose?
We recommend x2y or full CN. Both provide fast EOCrosses that are efficient enough to allow planning the first pair later on.
For the rest of the tutorial we will choose x2y since the writer is more experienced in that option.