DanSmith

"Is it common for people to use white or pink noise and apply EQ filters (high pass and low pass) to achieve only the desired frequency range?"

Mike: I did several builds over the years trying to tackle this problem. I wanted a range of frequencies to be present in the environment. Obviously adding audible noise causes several other issues to deal with.

The best method I came up with was to introduce the frequencies silently in the form of light. By transforming sound into light and then recollecting the light with a sensitive solar cell. Some voices come across as whispers and some simple analysis shows that those type of voices are usually missing the fundamental frequency to give the intonation of human voice.

My hypothesis was that by introducing a blanket of frequencies we might cause beat frequencies and/or provide the fundamental frequency needed to 'round out' a voice. As best I can tell, through using shielding and as many controls as you can, it's POSSIBLE this hypothesis MAY be true.

I'm currently working on a setup that uses sound transformed into light and an acousto-optic tunable filter that is able to split a laser into different bands like a prism before being collected and demodulated back into sound. Hopefully in the coming years I will be able to design a solid study to really look into what effect, if any, introducing a broad range of frequencies actually has on voice quality.