Convert Frequency from kilohertz (kHz) to other units
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What is a Kilohertz (kHz)?

A kilohertz (kHz) is a unit of frequency in the International System of Units (SI), equal to one thousand hertz (1000 Hz). The plural form is kilohertz.

It's a term you'll encounter in everything from sound and radio to the history of computing.

Key Takeaways

• A kilohertz (kHz) is a unit of frequency equal to 1,000 hertz (Hz).
• Human hearing typically ranges from 20 Hz to 20 kHz.
• It is the standard unit for AM radio broadcasting frequencies.
• Early computers had processor speeds measured in kHz.

How Does Kilohertz Relate to Human Hearing?

Your ability to perceive sound, from the deepest bass to the highest treble, is measured in hertz and kilohertz.

The range of human hearing typically falls between 20 Hz and 20 kilohertz (20,000 Hz).

The frequencies most sensitive to the human ear, particularly for understanding speech, are concentrated in the range of 1 to 4 kHz. This is why audio engineers and audiologists pay close attention to this specific spectrum when mixing music or conducting hearing tests.

Why Do AM Radio Stations Use Kilohertz?

Kilohertz is the fundamental unit used for AM (Amplitude Modulation) radio broadcasting.

AM radio stations operate in a frequency range from 535 to 1705 kilohertz in the Americas, often referred to as the medium wave band.

Each station is assigned a specific frequency, like 820 kHz or 1010 kHz, which your radio receiver tunes into to capture the broadcast signal. This contrasts with FM radio, which broadcasts in the much higher megahertz (MHz) range.

Where Else is Kilohertz Used in Technology?

While today's computers boast processor speeds in gigahertz (GHz), the pioneers of computing operated at much slower speeds measured in kilohertz.

For instance, the Intel 4004, the world's first commercial microprocessor, was released in 1971 with a clock speed of just 740 kHz.

Beyond computing, kilohertz frequencies are also crucial in other technologies. A key example is medical ultrasound, where transducers emit sound waves in the high kHz to low MHz range to create diagnostic images of the body's organs and tissues.