How to play with different voices in mespeak.js

Question

I am currently working on mespeak.js

I want to use a client side library that helps me convert text to speech without using any installed voices. mespeak.js helps to work on this problem but has very robotic voice. I want to use other voice but have a hard time configuring it in mespeak.js.

I tried following the documentation and it doesn't yields the required result and stuck with error. link I tried implementing something similar to this.

{
  "voice_id": "mb-en1",
  "voice":    "name english-mb-en1 \nlanguage en-uk  3 \nlanguage en 2 \ngender male \nvoicing 150 \npitch 82 117 \nmbrola en1 en1_phtrans",
  "voice_encoding": "text",
  "files" : [{
      "path": "path/to/en1_phtrans",
      "data": "en1_phtrans",
    }]
}