Help with making a custom office chair for Music listening

Hi all,

I need help with ideas how to make an office style chair for music listening. Although simple & basic it has to have the following:

- be height adjustable
- what ever height it's set on it has to be ridged not like typical gas lift chairs as they have a bit of give which wont work for what I want as it dampens/destroys body movements.

- a few inches back & forth movement
-about an inch side to side movement
- it has to be heavy duty, most office chairs will not hold up to this kind of abuse.
-just the chair platform it self with no back support or arm support of any kind.
-on wheels to move around easy.

The closet I got to this was moding a basic office chair that was damaged, surprisingly after some welding it did almost everything, but the gas lift unit ruins it, as it absorbs body movements, and I know no way to lock it into position.

Please help, thanks

Why is dampening a problem when you're listening to music?