The Shimmer by David Morrell

I don't think I need any more character."
    "Then I'll spare you a repeat of the experience. But since you've been in firefights, there's one relevant thing I'd expect you to have learned."
    "Yes, sir. And what is that?"
    The colonel gestured toward the disintegrated target of the woman in the white medical coat.
    "You don't stay alive long if you take the time to worry about innocent bystanders, especially in a firefight. Sure, maybe some pussy reporter'll accuse you of a war crime, and maybe the Army'll cave in to the grumbling of a bunch of politicians and put you on trial. But you'll still be alive, and ten years of hard labor is better than getting shot to death by a supposed innocent bystander who thinks you're a fool for not killing him. Or her. There could easily have been a suicide bomb under her medical coat."
    "Yes, sir."
    "It's going to be hard for anyone to outdo my new record."
    "Yes, sir," the sergeant assured him emphatically.
    Raleigh's cell phone buzzed. He pulled it from his belt and spoke into it with authority. "Raleigh here."
    What he heard made his jaw tighten.
    "I'm on my way."

    Chapter 16.
    The strange sounds seeped past the closed door of the command center one level below the underground shooting house. Raleigh heard them the moment he hurried from the elevator. He passed an armed sentry, jabbed numbers on a security pad, and pushed the door open.
    The full volume of the sounds drifted over him. A dozen civilian researchers studied various electronic displays, assessing, measuring, calculating. He'd never seen his research team look so intense. Amid the multitude of glowing instruments and pulsing meters, he hurriedly closed the door and tried to identify what he was hearing. He was reminded of music, but these weren't like any notes he'd ever heard. Granted, they were processed through a computer's synthesizer program, which gave them an artificial tone, but he'd heard synthesizer music before, and that wasn't what created the distinctive feeling these sounds inspired.
    First, the rhythm sank into him. It drifted, so hypnotic that it seemed to counteract his quickening heartbeat. Second, the notes vibrated in a way that made the colors in the room appear to intensify.
    Third, the melody--which didn't have any pattern that he could detect--made his mouth feel as if he'd just sipped . . .
    "You're tasting orange juice, aren't you, Colonel?"
    Startled, he looked up. A researcher had noticed him draw his tongue along his lips.
    "That's right. How did you know?"
    "We all are. Do the colors seem stronger as well?" The man's eyes flashed with curiosity.
    Raleigh nodded, squinting to subdue the sudden intense glow of the monitors.
    "You can almost feel the music as much as hear it," the man continued.
    "Yes. A ripple of warmth along my skin."
    "It's called synesthesia."
    Raleigh was blessed with an encyclopedic memory. He quickly identified the word. "A process by which the stimulation of one sense somehow causes other senses to be stimulated as well."
    "Exactly," the researcher said. "In this case, we're not only hearing these sounds, we're also seeing them, feeling them, and tasting them."
    Raleigh glanced from one scientist to another. He thought of the projects his team had been developing. One of his favorites was a method of transmitting ultralow sound waves that affected the physical and psychological well-being of an enemy. The enemy wouldn't be able to hear the sound and hence wouldn't be aware of the aural bombardment. But the effects would be profound. In the 1990s, an early version had been tested around the isolated community of Taos in northern New Mexico. For months the valley had been saturated by a low-level frequency that in theory should have been beneath the range of what human and animal ears could register but in actuality turned out to be just barely detectable. Locals who were made nervous wrecks by it took to calling it the "Taos hum." Dogs and cats showed visible pain, scratching