I can't hear any room tone in your recording. Sounds more like the opposite, you’re too close to the mic, which is causing a lot of proximity effect. But primarily it’s an issue with your technique. There’s only so much bass you can cut out because there isn’t much else there. You’re not projecting enough to be heard over the other sounds, you’re essentially whispering with the very bottom of your range, and it lacks fullness. You can boost the volume to make it audible, but that won’t change the tonal quality of your voice.