The sound effect "Countdown-Boom" (specifically ID 76577, often credited to Russintheus) is a popular, dramatic cinematic effect. You can download it for free from Pixabay . Format: MP3 Source: Pixabay License: Free for use under the Pixabay Content License.
I can give you more specific advice on editing or find the perfect audio to match! Countdown-Boom | Royalty-free Music - Pixabay Download countdown boom 76577 mp3
To make your project (video, presentation, or audio) more effective: I can give you more specific advice on
If this specific sound isn't perfect, you can find similar audio at these sources: Do you need other sound effects to go with it
Use software like Audacity to increase the bass if the boom needs to sound more cinematic.
are you using this for (e.g., YouTube video, presentation)? Do you need other sound effects to go with it?
Based on your request, I have identified the specific "Countdown-Boom" sound effect you are likely looking for and created a helpful guide for using it.