Subwoofers (and the air itself!) are NOT in-phase with your mixer and amplifier.

You are the only one in the web teaching actual science with audio engineering. Things most audio “engineers” have no clue about. Thank you

You've gotta be one of the most passionate, most interested, most curious, and smartest people in audio on the Internet right now.

If you have a solid understanding of kinematics and fourier transforms it makes this stuff easier to grasp, but that is honestly more esoteric than what most people need to actually apply this in practice. This is BY FAR one of the best intuitive explanations of how phase works with sound reinforcement that I have ever come across. It's something I've understood but always had a hard time explaining in detail because it's such a math heavy topic to really get in to. Great job bridging that gap! Would love to see more.

For the first time ever, I finally understand the affects that phase response has on a system because of this demo. Thank you!

This is now one of my favourite videos on tech. It's just... the applied sound engineering and exploration, I had to rewatch it to gain insight

An insane amount of useful information and I’m all here for it! The visualizations are super helpful too, thank you so much for the effort!

Love it, this reminds me greatly of my electrical engineering classes at uni. You're like connecting all the dots when it comes to audio applications

Most educational half hour I've spent in a long time. Awesome. Thanks!

Amazing! Amazing amazing. This is the kind of content I've always wished existed. Now we just need a pipeline for absolute beginners to get to this point

That was one of the best descriptions I've ever seen for the behaviors of the "signal, driver, soundwave, mic" relationship. It's a very complicated process, and this is a great way to break it down and understand each component. For your next challenge, you should try to do the same type of breakdown for a bass-reflex cabinet. That is one of the most important and least understood elements of speaker/cabinet design. I've been struggling to wrap my head around it for ages.

Great video. I really like how you've taken something that can very dry, mathematical and abstract and make it understandable in an intuitive way

I believe there's a term called Jerk when decribes the rate of cahnge of acceleration. Also wonder how damping factor and power bandwidth comes into play. Awesome video, thanks!

The phase relationship between the input signal and the output from the speakers is actually much more complicated in practice. The reason is that the equation m.a+c.v+k.x=F(x) applies to established sinusoidal stimuli. In practice, the musical signal is not like that. It is rather a transient process in which the behavior of the speaker is determined by an inhomogeneous system of differential equations, which makes the issue of instantaneous phase shift quite complicated. Thank a lot for video.

When i was at university we learned that particle velocity and sound pressure are out of phase in the nearfield and in phase in the far field. And considering that the Driver stimulate the particles directly, resulting in particle velocity and the microphone converting sound pressure to electrical current, your results would make sense (basically also what you explained at 23:55). It would be interesting to see the same measurements in the far field.

Hands down the best video I've seen describing audio phase relationships both in thoroughness and in critical thinking. I can only hope for more people to enjoy this!

In a car, what pushes you (pressure) back in the seat? Acceleration. Not speed and not position. Similarly the air in front of the speaker cone becomes pressurised by the acceleration of the cone, not the speed or the position. This should also explain why high frequencies have more acoustic power thab lows at the same driver displacment - acceleration is higher. EDIT: In hindsight I misspoke. Pressure is not created by acceleration, but sound (modulation of pressure) is. Thus g-force felt in a car is analogous to sound energy.

This must be one of the most beautiful videos I have seen. I watched it 3 times already and will keep doing it. It explains so much and rises so many new questions...

The animation 24 minutes in was such an awesome lightbulb moment, thank you!! Epically useful video!

That's an incredibly inciteful tutorial. I had no idea how much went in in the journey of music through my sound system! Terrific demonstration!

I totally love the detailed technical explanation. Fantastic video. Little brain numb (in a good way) after watching it with high focus. I learned quite a lot from this video. Thanks for the great work! I really didn't expect to get info on both the advanced electronics I expected, but on fluid dynamics as well. I never thought about that before, but it really does make sense having to factor air pressure, displacement etc. And that's all Fluid Dynamics/Mechanics. Totally awesome.