HI HIGHS - > 8000 Hertz This range is where you find cymbals and higher harmonics of sounds. Boosting this range a little bit on certain instruments can make the recording sound like a higher quality recording. Boosting this range too much can make it sound irritating. Ovella 32 70 32 69 00 Indoor environments, city living, automobiles, exposure to electronic devices , EMF's (electro-magnetic fields), and environmental pollution all result in increased positive ions in the body, tilting the ratio of ions towards the positive. This results in a physiological imbalance, which may have d...