BTS Pro hands-on: Lightweight, great sounding, sweatproof headphones for athletes

There are several excellent Bluetooth earbuds for those who enjoy music while working out. 66 Audio just released its new generation BTS Pro headphones and they last more than 40 hours.
Written by Matthew Miller, Contributing Writer
Image: 66 Audio

Music can motivate you to run faster and work out harder. I've been running with Bluetooth wireless earbuds for years, so when I was asked if I wanted to try an on-the-ear style I hesitated at first since I thought they would be too big and cumbersome. I was wrong.

I was sent all of the details on the 66 Audio BTS Pro and spent the last 10 days or so testing out the electric green model. They fit well, sound great, last forever, and have excellent reception even across my dense body.

Wireless earbuds are great for those who participate in activities where a helmet or stocking cap is worn. However, earbuds usually have a maximum battery life of 8 hours or less because of their size, can work their way out of your ear, and can require various tips and fins to obtain a secure fit so there are reasons to consider other types of wireless headphones.

The BTS Pro has an advertised battery life of 40+ hours and after a few runs and listening to music during my commute I still have plenty of battery capacity left over. You could easily go a couple of weeks between charging with a regular exercise routine.


The BTS Pro headphones are available in electric green and lava orange colors. The bright green or orange box contains the headphones, a zippered carrying case, and a USB Type-A to USB Type-C cable. The headphones are charged up via USB Type C, which is becoming the new standard for Android smartphones and laptops. The headphones actually support quick charge technology so you can go from empty to full in 90 minutes.

The BTS Pro appear to be a very simple headphone with no size adjustments to make or earbud tips to swap out. They fit on the ear with the arm that connects the two sides slipping easily over the top of your ear and around the back of your neck to securely rest in place. Each headphone is covered with memory foam cushion material so that it is comfortable on your ear.

BTS Pro Bluetooth on-the-ear sport headphones: in pictures

The arm that runs around the back of your neck has two hinge points so you can fold down the headphones and carry them in the zippered hard shell case when you go to the gym or travel with the BTS Pro. The arm is made of flexible plastic and adjusts to fit around your neck in comfort.

The headphones only weigh 83 grams and are very lightweight for extended use. My ears are sensitive to long periods of pressure, which is why I never wear larger headphones, and after an hour or so I did feel a bit of pressure along the top of my ear the first time I wore them. However, after a few more hours of testing they fit well. I may have adjusted them slightly so there is no longer pressure on the one top area of my ears.

All the action takes place on the right headphone with the USB Type-C charging port under a port cover and five buttons integrated into the outside of the headphone. The buttons are used to power on and off the headphones, manage playback of your music, and manage phone calls. A microphone is also found on the right headphone. There are no buttons or ports on the left headphone.

The BTS Pro uses Bluetooth 4.2 technology with a range of 100 feet to connect to your device. 66 Audio uses its own patented 3D antenna RF technology to provide such long range coverage with the headphones.

I was able to turn the music on my iPhone 7 Plus and then go all around my house and into my garage without losing the connection. Even more important for me is the ability for the headphones to work while running. I am 6 feet, 1 inches, and currently weigh 255 pounds so am a bit dense in my upper body. Bluetooth headphones often cut out when my audio source, Apple Watch in most cases, moves to the opposite side of my body from the Bluetooth receiver. The BTS Pro never cut out and they sounded terrific.

The Bluetooth radio also supports aptX. A 500 mAh lithium polymer battery supports more than 40 hours of continuous playback or 400 hours of standby battery life.


Similar to what Jaybird provides with its X3 earbuds and MySound app, 66 Audio provides iOS support through an app for the BTS Pro. The Motion Control app can be connected to your headphones to provide custom equalizer settings, firmware updates, a button tutorial, and the ability to locate your BTS Pro.

When you tap on Find My Headphones you will hear a locator sound on the headphones and the longer the headphones stay lost, the louder the sound gets so you should eventually be able to find them quite easily. With the 400 hour standby time and 100 feet range, there really is no reason to turn off the headphones or ever worry about losing them.

There are several default equalizer settings, but you can tap and drag on the plot to customize your listening experience. That setting is then saved to the headphones and used for your music.

The iOS app also works on the Apple Watch. The Apple Watch app shows you the headset battery life and lets you change the equalizer setting too.

Experiences with the BTS Pro

I tested the BTS Pro with an iPhone 7 Plus and Apple Watch Series 2 in order to try out the Motion Control application. I also connected the BTS Pro to the LeEco Le Pro3 to test the audio through an Android phone. There is not yet an Android Motion Control app.

Even though I have never used on-the-ear headphones for running, I was surprised by how well they stayed in place as I ran. I never once had to mess around with them on my run and the sound played through flawlessly. Compared to earbuds that tend to work their way out or get pulled out when I turn my head too quickly, it was a real pleasure to quickly slip these on and never worry about movement or adjustment during my runs.

The volume is loud and I couldn't even turn my Apple Watch up all the way while running. The sound included good bass levels too and was very enjoyable for music and podcasts. With the custom Motion Control app you can customize exactly how you want your music to play so you can have heavy bass or more treble if you like.

I sweat a lot when I run and over the past week my runs have included light to moderate rain. The BTS Pro has withstood both of these sources of water and the sweatproof design has held up well so far. As I run through the winter, I will be testing out the ability of these headphones to survive the elements of Washington State.

You can also make phone calls with the BTS Pro, but just like most of these sport-focused models the call experience leaves a bit to be desired. People on the other end could tell I was on a headset so I wouldn't conduct a business call with them, but it works fine to let your friend or family member know when you will be done with your workout. There are more advanced Bluetooth headsets for business calls, such as the Plantronics Voyage 5200 so I wouldn't buy the BTS Pro if you need to make a lot of business calls while out running.

The BTS Pro headphones are available now for $129.99. If on-the-ear headphones work for you and you don't need to wear a helmet during your activity, the BTS Pro is a fantastic set of headphones to use while exercising or even during your commute.

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