I remember my first HPS, circa '88. Traded some pot for it (one of the many things I have "bought" with weed).
I got in 3rd-hand, from a guy who got it from a factory that was being demolished where is was usedfor who knows how long.
It had a mechanical ballast, a huge heavy thing with wire's sticking out, totally ghetto-rigged.
And it was LOUD, like a Pinto idling.
I tried enclosing it to soundproof it but it got too hot. Even though I tried as hard as I could, I couldn't quiet it.
The worst part was that the grow space was upstairs from my living room, and when people came over they noticed it.
So until I could afford a new, quieter ballast only my closest friends could hang around in my living room, everyone else I visited with in the garage/rumpus room.
What a relief when I finally switched. An easily-ignored hum.
AND
The first indoor growbook I read, several months after I started, recommended changing the bulb every year. I had no idea how long that bulb had been used but I know for at least 3 years. I went out and bought a 430-watt full-spectrum bulb and man alive what a difference! It was probably more than twice as bright.
So yogi dc I recommend getting a new bulb for that set-up, and keep the old one for an emergency spare.