All products featured are independently chosen by us. However, SoundGuys may receive a commission on orders placed through its retail links. See our ethics statement.
Master & Dynamic MW09
Earbuds from Master & Dynamic can feel more like luxury jewelry than performance audio equipment. While we loved the design of the Master & Dynamic MW08, a couple of missing features made it hard to justify its high price tag. Can the newest wireless earbud model fill in the gaps? Find out in our Master & Dynamic MW09 review.
Editor’s note: this article was updated on Nov 5, 2024, to include a comparison to the Bowers & Wilkins Pi8.
- We tested the Master & Dynamic MW09 over one week. The earbuds ran firmware version V0.1.7.0, and the M&D Connect app ran version V2.0.6. The company provided the unit for this review.
Those interested in design and craftsmanship will appreciate the aluminum and kevlar designs of the various color options for the Master & Dynamic MW09. Anyone looking to show off the latest and greatest in wireless earbud tech may fancy the MW09. If you need exceptionally long battery life from your earbuds, the Master & Dynamic have the best battery life of any wireless earbuds we’ve tested.
What’s it like to use the Master & Dynamic MW09?
The Master & Dynamic MW09 has some of the nicest designs of any earbuds you’ll find. You can select an aluminum finish (silver, black, or gold) or a Kevlar finish for the charging case. You can also choose between green, blue, or gunmetal earbuds with the Kevlar option. Our silver aluminum package is one of the more modest options but still looks eye-catching, with sapphire glass adorning the back of each earbud. For an extra $30, Master & Dynamic lets you personalize your earbuds with an engraving.
Beyond their looks, the MW09 also feel very durable and well-built. The earbuds have an IP54 dust and water-resistance rating, which means you can wear them at the gym or beach without worry. The charging case is also IPX4-rated, so it’s okay if you get a few water splashes on it.
The downside of using aluminum, Kevlar, and glass instead of plastic is the weight. Each earbud weighs 8.1g, and the charging case weighs up to 63g, nearly double the weight of some plastic earbuds such as Apple AirPods. Master & Dynamic includes various silicone and foam ear tips, so I had no issues with comfort. You can use an ear tip fit test inside the companion app to help you find the right fit.
How do you control the Master & Dynamic MW09?
The MW09 uses push buttons to control playback. The left earbud houses the volume controls, while the right earbud has a multifunction button. It’s a bit strange that Master & Dynamic didn’t use the large glass panels for touch controls, but the physical buttons work fine.
| Multi-function button (right earbud) | Vol + (left earbud) | Vol - (left earbud) | |
|---|---|---|---|
Single press | Multi-function button (right earbud) Pause/play, answer call | Vol + (left earbud) Increase volume | Vol - (left earbud) Decrease volume |
Double press | Multi-function button (right earbud) Next track | Vol + (left earbud) | Vol - (left earbud) |
Triple press | Multi-function button (right earbud) Previous track | Vol + (left earbud) | Vol - (left earbud) |
Press and hold | Multi-function button (right earbud) Activate voice assistant | Vol + (left earbud) Ambient listening mode on/off | Vol - (left earbud) Noise canceling on/off |
As of writing, you can’t customize the onboard controls. You can enable or disable in-ear detection and set an auto-off timer from within the M&D Connect app.
Should you use the M&D Connect App for the Master & Dynamic MW09?
You should download the M&D Connect app to get the most from your Master & Dynamic MW09 earbuds. Beyond battery information and firmware updates, there are a whole bunch of features to dig into within the app.
You can select an equalizer preset inside the sound menu or make your own custom preset using the 5-band EQ. You can also switch between active noise cancelation (ANC) and ambient mode, depending on how much environmental noise you want to hear. There are also toggles to turn sidetone and audio prompts on or off.
You can enable or disable in-ear detection and the auto-off timer in the settings menu. There’s also an acoustic seal test here to see if you are using the right size of ear tips and do a factory reset if needed.
The final menu to explore is Bluetooth management, where you can quickly swap between devices using Bluetooth multipoint. Overall, this comprehensive app experience includes a lot of customization, and it matters most in sound quality and listening modes.
How do the Master & Dynamic MW09 connect?
The Master & Dynamic MW09 connects to devices via Bluetooth 5.4, the latest in Bluetooth technology. Having the latest Bluetooth tech future proofs the earbuds ready for advanced features such as Bluetooth LE and Auracast become more readily available in devices. In terms of Bluetooth codecs, the MW09 supports AAC, AptX Adaptive, AptX Lossless, LC3, and SBC.
With Bluetooth multipoint support, you can pair two devices simultaneously. I didn’t experience any connection dropouts during the testing period when paired to my phone and laptop.
The first time you take the earbuds out of their charging case they will automatically enter pairing mode. To manually enter pairing mode or pair to another device, remove the earbuds from their case and your ears and hold down the multi-function button on the right earbud until the LED light on the earbud starts pulsing.
How long does the Master & Dynamic MW09 battery last?
Battery life on the Master & Dynamic MW09 is incredible, which may also explain their weight. In our battery test, the earbuds lasted 15 hours and 54 minutes. This is the longest battery life we’ve seen on any wireless earbuds. Not only does this mean you won’t have to worry about putting the earbuds in their case throughout the day to charge them back up, but it also means the MW09 should have a much longer lifespan than other earbuds.
The charging case provides an additional 32 hours of battery life. You can charge the case via USB-C or wireless charging, though charging wirelessly takes twice as long.
Yes, the MW09 has exceptionally fast charging. The earbuds and case power up 50% in only 20 minutes of charging. That means you can get 8 hours of music playback time by charging these earbuds during your lunch break. Additionally, you can fully charge the earbuds and case in only 60 minutes when using the USB-C cable.
The case’s LED lights function when you open or close the lid. The middle LED is for the charging case, while the left and right lights correspond to each earbud. Green indicates 70-100% battery left, amber indicates 30-69%, and red indicates 1-29%. If you see flashing red or no light, the battery is empty.
How well do the Master & Dynamic MW09 cancel noise?
Loading chart ...
The ability of earbuds to control environmental noise heavily depends on how well they fit in your ears. Since the MW09 come with both foam and silicone ear tips in various sizes, they have an advantage in passive isolation compared to other earbuds. Foam ear tips block out noise better than silicone, as we’ve seen with other premium earbuds such as the Sony WF-1000XM5.
The Master & Dynamic MW09 includes many options for adjusting environmental noise. There are three different ANC modes: Max ANC, All-day ANC, and Adaptive ANC. Max ANC blocks out the most noise, so I mostly just used this mode as someone who likes to hear nothing but my music. Combining Max ANC with the foam ear tips reduces the loudness of most environmental noise by about 90%. Adaptive ANC actively adjusts the strength of the noise canceling depending on how loud your environment is, while All-day ANC keeps the ANC on a lower attenuation level.
If you are the type of person who likes to stay aware of their surroundings or eavesdrop on conversations, Master & Dynamic also has you covered. There are three ambient listening modes: Voice, Natural, and Awareness. These all amplify slightly different frequencies from your surroundings. Voice amplifies mid frequencies, Natural amplifies high frequencies, and Awareness amplifies low frequencies.
How do the Master & Dynamic MW09 sound?
Objective Measurements
Loading chart ...
Compared to our headphone preference curve, the default sound of the MW09 over-emphasizes all frequencies below 300Hz by about 5 dB. The earbuds also have a steep drop-off in the high frequencies above 8kHz, which makes bass sound comparably louder.
Audiophile EQ Preset
Loading chart ...
The Audiophile preset is (unsurprisingly) closer to our preference curve.
Bass Cut EQ Preset
Loading chart ...
The bass cut preset tones down the over-emphasized low-frequencies but still retains a lot of sub-bass.
Bass Boost EQ Preset
Loading chart ...
You should probably steer clear of this EQ setting.
Podcast EQ Preset
Loading chart ...
This EQ preset is pretty self-explanatory, though you also may like how it sounds with your music, as it is a relatively neutral frequency response.
Loading chart ...
In the chart above, the blue line is the frequency response of the MW09 without ANC enabled, and the yellow dotted line represents the frequency response when you turn on noise canceling. As you can see, ANC does slightly alter the way that these earbuds sound, boosting frequencies around 200-500Hz and 5kHz-10kHz by a couple of dB. This difference isn’t super noticeable, and you can easily EQ it away by dropping the 500 and 5k bands in the custom EQ.
Can you use the Master & Dynamic MW09 for phone calls?
The Master & Dynamic MW09 works well for taking phone calls. Using what Master & Dynamic calls an “A.I. enhanced talk solution,” the earbuds modify the incoming microphone signal to amplify the voice. You can hear this in action in our microphone samples below, as the microphone quality slowly improves after the first couple of seconds of each recording and dynamically adjusts to the vocal qualities of each person talking.
Master & Dynamic MW09 microphone demo (Ideal conditions):
How does the microphone sound to you?
Master & Dynamic MW09 microphone demo (Office conditions):
Master & Dynamic MW09 microphone demo (Street conditions):
Master & Dynamic MW09 microphone demo (Windy conditions):
Master & Dynamic MW09 microphone demo (Reverberant space):
The MW09 microphones handle background noise well. You can still make out everything the voices say in our simulated street and office environments. Master & Dynamic also implemented proprietary wind reduction tech on the MW09, which means you can still hear what is being said in our simulated wind environment.
Should you buy the Master & Dynamic MW09?
If you have the means to spend this much money on earbuds, you won’t regret buying the Master & Dynamic MW09. In addition to a luxurious design, the MW09 has the performance and features to support its high price tag. You get great noise canceling, the latest Bluetooth technology, and the best battery life of any earbuds we’ve tested.
While the sound is a bit too bass-heavy out of the box, the M&D Connect app makes it easy to adjust the sound to your liking. Without any other notable drawbacks, these earbuds are an easy recommendation for anyone looking for the most premium wireless earbud experience.
How do Master & Dynamic MW09 compare to Master & Dynamic MW08?
The MW09 is a noticeable upgrade to the previous model, the Master & Dynamic MW08. The MW09 has built-in equalizer functionality, whereas the MW08 does not. This means you are mostly stuck with the bass-boosted sound of the MW08.
The MW09 also has nearly double the battery life of the MW08 and improved fast charging. The IP54-rated earbuds are more durable with the MW09 than the IPX5-rated MW08. The charging case of the MW08 also has no water resistance, whereas the MW09 charging case is IPX4-rated. Finally, the MW09 has improved noise canceling and microphone quality over its predecessor.
What should you get instead of the Master & Dynamic MW09?
At this price, there are a ton of great wireless earbuds. Our top dog for most people is the Sony WF-1000XM5. These earbuds have a good fit, are great at blocking out noise, and come with advanced features such as Sony 360 Reality Audio, $298 at Amazon.
If you have an iPhone, you can’t go wrong with the Apple AirPods Pro 2. Our biggest gripe is the lack of an EQ to adjust the sound, but otherwise, these earbuds are packed full of Apple-exclusive features you won’t find anywhere else, $239 at Amazon.
If money is no object to you, and you want a luxury product, check out the Bowers & Wilkins Pi8 ($399 at Amazon). The Pi8 cost even more money than the MW09, but offer superior sound quality.
Frequently asked questions
Yes, you can use Bluetooth to connect the Master & Dynamic to either an iPhone or Android phone, or even both at the same time.
Yes, the earbuds are IP54-rated, which means they can handle splashes of water from all directions. The charging case is also IPX4-rated so that it can handle some accidental water splashes.
Yes, the Master & Dynamic MW09 supports Bluetooth multipoint so that you can connect to two devices at the same time.
While these earbuds aren’t particularly designed for working out, they perform pretty well at the gym. There are no ear hooks, but the foam ear tips provide a secure enough fit for most people to run with. Water resistance means you don’t need to worry about sweat damage. A ton of bass provides a clear beat to power your runs.
Yes, the MW09 charging case supports wireless charging.