Encrypting a voice is essentially the process of transforming voice data (audio) into a format that can't be understood by anyone without access to a decryption key. Here's a simplified version of the process:

1. Digitization: The first step is to convert the analog voice signal into a digital format. This is commonly done with a process called Pulse Code Modulation (PCM).

2. Encryption: The digitized voice data is then encrypted using a chosen encryption algorithm and a unique encryption key. There are many encryption algorithms available, like AES (Advanced Encryption Standard), DES (Data Encryption Standard), RSA, etc. Each algorithm has its strengths and weaknesses, but AES is one of the most secure and commonly used methods. The encryption process converts the understandable voice data into an incomprehensible format.

3. Transmission: The encrypted voice data can then be transmitted securely over any communication channel.

4. Decryption: On the receiving end, the encrypted voice data is decrypted using a decryption key, which should match the encryption key used at the sender's end. If the correct key is used, the original voice data can be reconstructed perfectly.

5. Digital-to-Analog Conversion: The decrypted digital data is then converted back into analog form so that it can be understood as sound.

This is a very simplified version of the process. In practice, voice encryption often involves more advanced techniques like secure key exchange protocols, compression to reduce the size of the voice data, and error correction methods to ensure the voice data isn't damaged during transmission.

It's important to note that encryption doesn't prevent someone from intercepting the voice data, but it does make the intercepted data meaningless unless the interceptor has the correct decryption key.