What is a DSP? (Digital Signal Processor)

If you’ve ever wondered how a microphone can clean up your voice as you speak, without you touching a single setting, the answer usually involves a DSP. Short for Digital Signal Processor, it’s a small, specialized chip that processes audio in real time, and it’s a big part of why modern microphones sound as good as they do straight out of the box.

This guide covers what a DSP actually is, why it exists, and where you run into one every day.

Before digital processing, shaping audio meant physical, analog gear. A compressor was a rack unit. An equalizer was a dedicated box with knobs and dials. Every effect needed its own piece of hardware, wired together in a chain, and that chain never changed unless you physically swapped equipment.

Digital signal processing changed that. Instead of shaping a continuous analog wave with physical circuits, a DSP converts sound into numbers, does math on those numbers, and converts the result back into sound. Once audio exists as data, you can apply almost any effect (filtering, compression, noise reduction) through calculations rather than physical components. That opened the door to processing that’s smaller, more flexible, and often better, without a rack full of gear.

A DSP handles three basic steps, all fast enough that you never notice a delay:

• Sampling. An analog-to-digital converter takes the incoming sound wave and measures it 44,100 or 48,000 times per second, turning it into a stream of numbers.
• Processing. The DSP chip runs calculations on that stream of numbers. This is where effects happen. Depending on the math applied, you get filtering, compression, noise reduction, or any number of other changes.
• Conversion back. A digital-to-analog converter turns the processed numbers back into a sound wave you can actually hear, whether that’s through headphones, a speaker, or a recording.

What matters here is where the processing happens. A DSP built into the device handles all three steps on the spot, so there is no round-trip of sending audio to your computer, processing it there, and sending it back. That round trip is what adds noticeable delay with software effects, and it is why onboard processing feels immediate when you monitor your own voice.

Microphones are one of the most common places you’ll run into DSP, especially now that many mics process audio themselves instead of relying entirely on your computer:

• USB streaming microphones often run DSP onboard to clean up your voice before it ever reaches your recording software.
• XLR audio interfaces use DSP to apply effects like compression and EQ to a microphone signal in real time, without a separate mixer.
• Headset and gaming mics use DSP to reduce background noise so your voice comes through clearly during calls or matches.
• Conference and webcam mics rely on DSP to isolate your voice from room noise during video calls.

In each case, the appeal is the same: processing happens on the device itself, so your voice is already cleaned up by the time it reaches your computer.

The math running on a DSP chip usually falls into a few familiar categories:

• Equalization (EQ) boosts or cuts specific frequency ranges, useful for adding warmth or reducing muddiness in a voice.
• Compression evens out volume differences, so quiet moments come through clearly and loud moments stay controlled.
• Noise reduction identifies and reduces steady background sound, like a fan or air conditioner, without affecting the wanted signal.
• Limiting caps a signal at a maximum level to prevent distortion when it gets unexpectedly loud.

Any single device might use one of these, several together, or a chain of them in sequence. The specific mix depends on what the device is built to do.

Elgato builds DSP directly into some Wave devices through Wave FX Processor, an onboard chip developed with LEWITT Audio. Devices like Wave:3 MK.2, Wave XLR MK.2, XLR Dock MK.2, and Wave XLR Pro run effects like a low-cut filter, expander, compressor, equalizer, and Voice Tune directly on the hardware, so your voice is processed before it ever reaches your computer.

Because the processing happens on-device, you hear your processed voice through your headphones in real time, and the effects follow your microphone into every app automatically. Wave FX Processor also handles Clipguard 2.0, which prevents distortion at the hardware level rather than fixing it afterward.

If you want a full breakdown of how these effects work together, check out our guide on Wave FX: Studio-grade sound from your mic. And if you’re wondering how DSP compares to software-based plugins, our guide on What is a VST? covers that distinction in more detail.