Dedicated hardware isn't the only way to get instant sound triggering during a stream. Setting up sound effect hotkeys through software alone can achieve much of the same speed and convenience, using just your existing keyboard.
Why hardware isn't strictly necessary
Dedicated software combined with your existing keyboard can achieve instant sound triggering without needing a separate physical macro device, making this a genuinely accessible option for anyone not ready to invest in additional hardware. 
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Software as a genuine alternative
While dedicated hardware offers a dedicated physical button for each sound, software-based hotkeys accomplish the same core function — instant triggering without navigating a menu — using hardware you almost certainly already own.
Setting up the software side
Audio routing or soundboard software that supports keyboard shortcut assignment lets a specific key combination trigger a chosen sound file through your stream's audio output, achieving the same instant playback a dedicated device would offer.
Choosing the right sounds to map first
Starting with a focused set of your most-used sounds, assigned to keys that are easy to remember and comfortably reach during a live stream, tends to work better than trying to map an overwhelming number of sounds all at once.
Avoiding hotkey conflicts
Choosing key combinations not already used by other software or the games you regularly play helps avoid accidental conflicts, making it worth testing your full setup before actually going live with it.
Building toward a more advanced setup
Once a software-based hotkey system feels comfortable, some streamers eventually add dedicated hardware for even faster access, similar to the more advanced setup covered in how to use stream deck buttons for instant sound effects, though it's entirely optional rather than required.
Conclusion
Sound effect hotkeys prove that instant sound triggering doesn't require any special hardware investment. Browse SoundGIFs' sound effects library for more sounds worth mapping to your next hotkey setup.