The ATH-CKR35BT headset is another example of audio-technica high-performance gear.

Is it not amazing that we can listen to music, watch movies, play games or listen to audible books wherever our smart devices allow.  We have the choice of what to watch, what to listen to, when to listen and with a variety of options on the market, what type of speaker to utilize.  Whether we use the included device speakers, accessory Bluetooth speakers, or any number of on-ear, over-ear, or in-ear options on the market, we have so many choices available.  I have tested numerous types of headphones and often end up with over-ear and in-ear systems.  I have not been a fan of earbuds, nor on-ear systems, as you often have to crank up the volume, and the bass remains less impressive.  For longer listening sessions, I have tended to shy away from in-ear systems due to canal fatigue.  However, the audio-technica ATH-CKR35BT in-ear earphones proved to be the exception to the rule.

Audio-technica ATH-CKR35BT REVIEW
The product arrived in a pristine, clean-white, 4 13/16 inches wide by 6 3/16 inches tall by 1 3/4 inches thick cardboard retail package.  The cover showed a large vibrant image of the black in-ear earphones with blue accent.  Displayed at your top left and along the backing of the earphones, audio-technica placed their classic logo (nested triangles inside of a circle).  I enjoyed the packaging and appreciated the use of contrasting colors.  The black font upon white background provided a vivid, eye-catching image.  The Bluetooth 4.1 headphones promised 7 hours of continuous usage, an included microphone for answering calls, controls for volume/music controllers, 9.8 mm high-performance drivers, and compatibility with the AAC (Advanced Audio Coding) codec.  If you are not familiar with the AAC codec, it is currently the preferred audio format for HD music/video.  It is the successor to the MP3 format, is considered a lossy audio system (lose some data and less perfect than the original), and is typically best suited for mobile devices.  The back of the packaging showed an exploded side-view image of the black/blue earphone towards your top left.  Refreshingly, they provided a clear-window along your top right, which allowed you a simple glimpse of the quality earphones.

Opening the packaging, you will first need to slide out the plastic tray before accessing the 0.5 ounce, 21-inch long earphones.  Beneath the internal plastic tray, audio-technica provided a well-stitched, 3 inches wide by 4 1/2 inches tall, black nylon drawstring bag.  Inside of the bag, you will find a reasonable 13 inches long USB-A to USB-micro cable and accessory XS, small, and large Ear tips (medium tips were pre-installed).  Resting freely within the box, you will also find multi-lingual caution and quick start guides (English, French, German, Spanish, Portuguese, Russian, and three character style languages that I could not identify).  I appreciated the succinct eight-panel quick-start guide and the intelligently utilized images.  We have all heard multiple times that a picture is worth a thousand words.  In this case, audio-technica successfully utilized their images to detail their product.

Audio-technica ATH-CKR35BT REVIEW
To start, you will need to charge the earphones.  When you plug the micro-USB into the side of the controller (3 1/2 inches distal to the right ear tip), you will notice a red LED along the side of the control box.   It took about an hour for this to change to a blue LED (2.5 hours from completely dead).  Once fully charged, you can hold the center power button for 3 seconds and notice the red/blue alternating LED.  Next, you can navigate to settings on your smart device, then to Bluetooth and then select ATH-CKR35BT.  Upon pairing, you will notice that the LED on the controller will flash blue.  There are three buttons on the controller, each with a short press/long press option.  If you press the volume up, “+” button or the volume down “-” buttons, you will be able to increase or decrease the volume of the earphones.  Interestingly, this does not control the volume of your phone and whether this is a pro or a con is still debatable.  Long presses of the same buttons will advance to the next or previous track, respectively.

The central button will play/pause a song/music and will also turn off the device after 2 seconds of being held.  If a phone call is incoming, you can short press the center button to pick up/hang-up and use the volume-up and volume-down buttons to adjust the audio.  The microphone is conveniently located within the control module near your right ear and did an above-average job of capturing sound.  I have found that the closer that the microphone is placed to the jaw or the mouth, the better the sound.  The microphone proved to be okay for calls but still suffered from a tunnel-like sound, similar to other in-ear microphones.  The single in-ear Bluetooth headsets, with microphones near the jaw, seem to perform better at phone calls.  Interestingly when paired with my phone, there was a high pitched whirring noise that was not present when the phone was off.  I only noticed this when looking at websites or between songs but not while listening to music.  I did find it refreshing to not hear typing sounds through the earphones.

We all know that fit and sound are the two major criteria for a good pair of earphone/headphones.  The earphones had the medium tips installed, which proved to be too big for my ear canals.  The tips were easy to remove/exchange by simply pulling them outward.  I tried the small and then the extra-small and enjoyed the comfort of the smallest tips. The fit was incredibly secure, comfortable and there was no wiggle in my ear canals.  With increased movement, the control box did pull downward on the right ear.   If you do not use the clip, it can pull out of the canal with turning, jumping and more extreme movements.  I do not know why they included the secondary 1 15/16 inches wide by 5/8 inches tall by 1/4 inches thick box located just about nine inches from the left earphone.  The clip could have attached to the cord instead of to the box.  I did like the audio-technica label on the box and that the clip was included, but it seemed to add extra weight to the entire structure.  Personally, the box should have been limited to the width of the clip.  Ultimately the lapel clip was incredibly secure and was an essential part of this kit.

To test the sound, I navigated to and tested the earphone frequency range.  The packaging promised 5Hz to 24,000 kHz but the human ear can only hear from 20Hz to 20,000 kHz and even this is limited based on age and ear health.  Using the low-frequency range test, I was able to appreciate sound starting at 20Hz, which was exceptional.  My typical upper audible frequency is 15-16 kHz, and the audio-technica earphones did not disappoint with the high-frequency range test.  The stereo perception testing and left/right/center testing through the site also passed with flying colors.  I liked the ability to adjust just the headphone volume, instead of my phone volume.  This allowed me to use my phone at my intended volume and then adjust the volume in my ears when I needed to.  I ran this pair of headphones through my usual gauntlet of songs: “Bright Lights Bigger City” from Cee Lo Green, Dark Knight Rises “Why So Serious? Joker Theme” and the opening from Star Wars Episode 3 Attack of the Clones.  I was pleased with the bass.  It was not overpowering and strong enough to support the sounds from the Gladiator Soundtrack.  Johnny Cash and Josh Turner sounded crisp and clear, and the experience was enjoyable.

To test the upper range and the staging, I love to use Horikawa Wandering, Far and Away Soundtrack, Pentatonix and the Braveheart soundtrack.  I find that instrumental pieces, namely anything by John Williams, more accurately separate the stronger from weaker earphones.  The sound quality of in-ear systems is highly dependent upon the ear canal fit.  During my testing, the sound was better as I decreased the size of the tips and experienced better fit.  The sound was full, vibrant and lively.  I love older music, and once the above tests were complete, I moved to comfort music by CCR, Beach Boys, Alabama and even older music from the 60’s and 70’s like Lean on me, Earth Angel, Stand by Me, My Girl and many others of the era.  When tired of music, I turned to audible and enjoyed The Templar Legacy by Steve Berry.  I was very pleased with the earphones lying supine, resting on my side with my ear resting on my pillow and while jogging on the treadmill.  I really liked the small ear tips and how they were able to rest inside the ear.  Many larger ear tips become painful when you lay on the ear and the ATH-CKR35BT did not suffer from this problem.  Definitely consider these earphones for day to day usage, as they are well made.

audio-technica in-ear
I enjoyed the earphones, the black drawstring bag, the weight/fit and comfort of these earphones.  Although I did not understand the size of the secondary, non-controlling box, the clip proved to be integral to the overall fit of the device.  I was pleased with the full sound and balance, and the earphones passed all of my tests.  My two complaints about this device revolve around the non-controlling box and background whining noise between songs and during dead time.  The control button scheme worked well, and I accidentally found Siri control by pressing the center control button twice.  Although they have no active noise cancellation technology, the ATH-CKR35BT decrease ambient sounds passively by blocking your ear canals.  I would rate the complete experience at 4/5 stars and would encourage these for teens, college students, athletic/gym use and day to day enjoyment.  When you purchase a product from audio-technica, you can expect excellence.  They surely brought their A-game, and the ATH-CKR35BT earphones did not disappoint.

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