- YouTuber PlasmatronX creates a testbed to visually map the movement of spatial audio waves
- This requires a lot of custom design, including building your own multi-channel amp.
- You can download the 3D print files and code to create your own testbed
Have you ever wished you could see sound waves in your bedroom? It turns out all you need is a guinea pig and a CAT: Computer Acoustic Tomography.
In a fascinating and fun video that captivated the entire TechRadar AV team and is well worth 11 minutes of your time, YouTuber PlasmatronX creates a test rig that allows him to visualize how sound waves move around the room.
This visualization can then be used to compare the performance of different sound setups, such as the difference between a soundbar and a full surround speaker setup.
Look on it
Put a guinea pig in a test bench
PlasmatronX clearly doesn’t take things too seriously. His experiment uses several stuffed animals, including a toy guinea pig to sit in the sound backup system, because it is close enough in 4:1 scale to his own head, and at one point he suggests that his experiments with beam steering – using imperceptible delays to make sound appear as if it were coming from somewhere else – would have been more effective if he had fired beams from his own rear end.
The Guinea Pig is centered in a multi-speaker setup that can reproduce a pair of perfectly positioned stereo speakers, a soundbar, and a full 7.1 surround sound setup. You can easily see where the “sweet spot” appears in each setup and how soundbars can make sound seem like it’s coming from speakers that aren’t there.
The takeaway here is that your room is one of the most important factors in the sound you hear: the combination of audio reflections from walls and ceilings and the absorption of sound waves by soft furnishings such as your sofa or curtains will have a significant effect on what you hear.
This is especially important if you have a soundbar that uses an acoustic trick to create virtual speakers, playing sound intended to bounce off the walls and ceiling of your room. The more comfortable your front room is, the more audio it is likely to absorb.
This by no means reveals a big secret – which is why most of the best soundbars are calibrated in the room – but it’s still fascinating and the video is often a lot of fun, especially when PlasmatronX experiments with building its own amp and constructing soundbar waveguides with varying degrees of success.
If you fancy repeating the experiment with your own guinea pig, PlasmatronX has provided all the necessary code, 3D print files and schematics for download here.
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