How This Speaker Broke Physics.

This speaker breaks the laws of physics. Before we can appreciate how special this thing really is, we first have to learn a little bit more about how speakers actually work. Ever wonder why some speakers are bassy and others aren’t? I know it’s a weird question, but stick with me. When we think about things in nature that make a lot of bass, we think about large things with mass like a volcano, an avalanche, or a whale. Is the same true with speakers? Take the Ioud Micro Monitor and the Beosound Bang and Olufsen Explore. They’re about the same size, about the same weight, but have totally different bass responses. So, why are some speakers bassy?

Let’s look at the Yamaha HS5, a classic studio monitor. This is what we call a two-way speaker, meaning that this one speaker is actually two speakers. Up here, we have what’s called a tweeter, which handles the high frequencies, and down here, a woofer, which handles everything else. But for sub-bass, and I mean real low frequencies, we’re going to need something like this: a subwoofer. This is what you see in places where you need bass to really fill a room—movie theaters, concert venues, even some crazy home theater setups. This is Genelec’s 10-inch subwoofer. While size isn’t the whole story, having a big cabinet like this definitely helps you get a lot of bass. But if size isn’t the whole story, what makes a speaker bassy?

In the 1960s, engineers were beginning to ask this question themselves, specifically engineers at a company called KLH. Eventually, KLH co-founder Joseph Anton Hoffman came up with what we now call Hoffman’s Iron Law. It’s not exactly a law of physics; it’s more of a loose description of some of the physical properties of air, but it can be really helpful in explaining why some speakers are bassy and others aren’t. Here’s the gist of it: a speaker can be small, a speaker can be loud, and a speaker can be bassy, but it can’t be all three. You have to pick two. So, it can be small and bassy but use a ton of power, like the Devialet Phantom, or it can be small and efficient but not get very much bass, like an Echo Dot. It just can’t be all three.

That’s sort of the nail in the coffin for Bluetooth speakers, right? Bluetooth speakers need to be small so that they’re portable, efficient so that they can get loud without wasting their battery life, and bassy because that’s what makes them fun to listen to. So, what do we do? Well, if we actually go and read Hoffman’s Iron Law, we’ll realize it’s not as simple as it sounds. For it to be true, your speaker enclosure must have an airtight seal, which makes sense. Sound is air, and if air is leaking from your speaker, it could be making sounds you don’t actually want. So, what would it be like if our speaker had a hole in it? Do you remember this guy from the beginning of the video? There’s a hole right in the back. Yamaha did not make this an airtight speaker. Why would they do that?

When a speaker cabinet is sealed, the cone has to fight against all that air pressure inside the speaker cabinet. If you cut a hole in the box, the speaker cone can now move much more freely, meaning it can get way louder with way less power. Let me show you. A speaker with a hole in it is just a vessel with one opening, like this glass bottle. What happens when we move air in and out of this vessel? It resonates. And what happens if we do the same thing but with a bigger bottle? The frequency gets lower. The same thing happens with a speaker with a hole in it. The bigger the speaker cabinet, the lower that resonant frequency is going to be.

In the '50s, we didn’t know what to do with this resonant frequency, but now we know that we can very precisely tune the shape of the speaker and the shape of the hole to get a nice low resonant frequency that actually gives us a bass boost—with some costs. To get this bass boost, we still need a reasonably large speaker cabinet to ensure the leaky frequencies are nice and low. That’s why that Genelec sub from earlier was so massive. There are some tricks to get around this, like passive radiators, which JBL uses in a bunch of their Bluetooth speakers, but even that stuff won’t give you the same rich, full bass you get from a large speaker cabinet. While cabinet size isn’t the whole story for why some speakers make a lot of bass, Hoffman’s Law tells us that cabinet size is most of the story. For that reason, tiny little Bluetooth speakers are only going to be able to make so much real bass—or at least that was the case.

This is the Brain X by Brain Audio, and it’s the bassiest Bluetooth speaker I’ve ever heard. Brain claims all over the internet that this speaker breaks Hoffman’s Iron Law, which I was skeptical of at first. But then I actually used it. Even with a sealed subwoofer inside, this thing gets loud, has excellent battery life, and makes sick bass. So, how did they do it? They did it with a clever mechanism called a magnetic negative spring. We all know how a normal spring works: it has a resting place and an original position, and the more you stretch it away from that original position, the more force is created wanting to snap it right back. A negative spring actually has the opposite properties. It also has a resting position, and the more you pull it away from that resting position, the more force there is, making the spring want to explode further away from the resting position.

That force is actually perfect to counteract all that air pressure we mentioned earlier in the video. Remember how that air pressure is always going to be pushing back on the speaker cone, wanting to force it back into the speaker cabinet? Now we have a magnetic force counteracting all of it. It’s not quite that simple, though. The brain uses permanent magnets in its magnetic spring, and permanent magnets are not very smart because they’re literally rocks. To throw a little intelligence into the equation, the brain also uses a series of electromagnets to keep everything lined up. These electromagnets are not actually moving any air; they’re just keeping everything in the correct position for the actual speaker driver and that negative spring.

Even if it is a technological marvel, what’s it like to actually own it? I’ve been using this Brain X at home for a few weeks now, and I absolutely love it for listening to music and especially watching movies in wired mode. The bass totally rocks and is pretty much the smallest, most complete home theater setup you can have. The mid-range is surprisingly distortion-free. If you’re in the market for a Bluetooth speaker or want to replace an old cheap soundbar you have in your house and the $599 price tag meets your budget, I would definitely take a good, hard look at the Brain X.

Now, just because this speaker breaks Hoffman’s Law doesn’t mean it’s a magic speaker that will solve all of your audio problems. It doesn’t have the crystal-clear imaging and high-end that you would find on a studio monitor or even the Devialet Phantom, which is twice the price. It also has some latency that all Bluetooth speakers have, so if you’re using it in a home theater setup, you’re definitely going to want to use it in wired mode. But that’s not what this video is about. I got so excited about this thing because it’s proof that now is an amazing time to be an audiophile. I’m not talking about the old-school $2,000 preamp kind of audiophile. I’m talking about a new kind that has a deep appreciation for all the clever innovation that companies are bringing to the table right now.

There’s a HEDD Audio studio monitor that can seal and unseal their cabinets. There are PMC mastering stacks that cost six figures and look like they’re owned by the Terminator. There are the speakers on the MacBook Pro that use some of the craziest signal processing ever and totally deserve their own video. There are those wireless studio monitors by iK that get 16 milliseconds of latency streaming at 44.1 kHz/16-bit. How does that work? It’s uncompressed! When a company puts forward something this new and cool—a technology that they say can be scaled down to an earbud and up to a concert-level speaker—you’ve got to make a video about it. Ten years ago, a speaker this size just couldn’t make this much bass.

I hope this video inspires you to go and read the manual for your speaker and learn all about the cool things that it’s doing under the hood. I hope this video inspires all the cool speaker manufacturers out there to be more transparent about how their stuff actually works (looking at you, Apple). And I hope this video helped spread the word about some really cool tech. In the meantime, I’m Ellis. This is the studio. Thank you for watching. Like and subscribe, and go watch Dune 2. It’s like the best movie ever.