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Drop + Grell TWS1X wireless IEM review: Exceptional sound in a frustrating package

Drop tapped an ex-Sennheiser engineer to help produce audiophile-level, truly wireless IEMs. The result is a pair of headphones that absolutely nail the sound quality but falter in too many other areas.
Written by Michael Gariffo, Staff Writer

As truly wireless earbuds grow in popularity, some manufacturers focus on their convenience, worrying more about compact charging case size and ample battery life than audiophile-level sound. On the other side of that coin is Drop. 

Drop, originally called Massdrop, started out as a purveyor of group buys, a way of securing discounts on existing products and paying for initial manufacturing of new products that's similar to crowdfunding. Since then, the online retailer has grown to produce its own branded products in collaboration with some of the top names in the audio and mechanical keyboard communities. 

To make an audiophile-grade pair of truly wireless earbuds, or IEMS (In-Ear Monitors) in this case, Drop tapped Grell, a company founded by former Sennheiser engineer Axel Grell. The result is the Drop + Grell TWS1X IEMs, or what I have come to know as one of the most frustrating-yet-still-excellent-sounding pairs of earbuds I've ever used. 

If you'd like to know how one of the best-sounding wireless earbuds I've ever experienced nearly drove me insane, read on and find out. 


Drop + Grell TWS1X IEM

2.5 / 5

pros and cons

  • Exceptional sound quality and shockingly roomy soundstage
  • One of the best ANC implementations I've used in a true wireless earbud
  • Secure fit with the right accessories attached
  • Impressive battery life
  • Problematic Bluetooth when connected to most products
  • Buds fit too tightly into charging case
  • Weird decision to reverse left and right bud placement in case
  • Requires wingtips to feel completely secure in ear

Build and design

Like just about every pair of truly wireless earbuds on the market, the TWS1X IEMs come with a charging case. This case immediately communicates that these are a different beast from your standard wireless earbud fare. Rather than opting for the rounded, capsule-like shape most manufacturers choose (Apple, Jabra, Anker, etc.), Drop and Grell instead chose a beefy oval with a flat top and bottom. 

Drop + Grell earbud charging case
Michael Gariffo

This results in a weight of 2.3oz, or almost twice what Apple's AirPods Pro weigh in their charging case. A large portion of this weight is from the metal exterior shell, which provides the unit with a satisfying feel in the hand. I firmly believe half the fun in using truly wireless earbuds is playing with their cases as a fidget toy, and the Drop + Grell take on the genre serves to be a satisfying plaything in the hand. 

When it's not occupying your digits, the case can be charged via either USB-C or Qi wireless charging.

Once you open that charging case, things get a bit…stranger. Take a look at the image below and note the left and right indicators. You're not hallucinating; they really are backward. This means the earbud that rests on the left side of the case is shaped for your right ear, while the one on the right is used in your left. This caused me some initial cognitive dissonance upon first opening them. I legitimately wondered for a moment if I'd forgotten my left and right. 

This decision seems likely to have been made to fit the charging case's included battery without adding even more bulk. Although, admittedly, this is a guess based on the placement of the charging contacts within the case and on the earbuds. 

Drop + Grell earbuds with charging case open

Something just doesn't look right...

Michael Gariffo

More: Marshall Motif ANC review: Wireless earbuds that rock...until they stop

The shaped slots for each bud ensure that they will rest securely against their charging contacts. This was far from a mechanically perfect setup, however. We'll cover more about why down below. 

Each earbud is dominated by a large, round outer plate that serves as its control surface. The left and right sides each have a list of available medial control functions based on taps, swipes, and holds contacting their touch-sensitive surfaces. The lack of mechanical switches means almost no inward pressure is necessary for actuation, preventing the uncomfortable sensation caused by forcing an earbud tip into your ear canal.

That roundness is interrupted on its edge by a small stem that houses part of the buds' "Multilayer Turbulence Eliminator (MTE) microphone array," powering its ability to serve as a wireless headset as well. The combination creates a largish aesthetic, making them far more noticeable than compact solutions like the Jabra Elite Line, but less obtrusive (thanks to their short stems) than Apple's AirPods Pro or standard AirPods

More: Don't buy your AirPods from Apple! These are the best deals

The tips of the earbuds feature a fairly standard friction-fit connector for replaceable tips to be pushed onto, with a total of three pairs of silicone tips and two pairs of foam tips, both in various sizes, included in the box. 

Drop + Grell earbuds' included accessories

Top - included USB-A to USB-C cable. Middle row - included eartips (from left to right): medium and large foam as well as small, medium, and large silicone. Bottom row - included "wingtips" (from left to right)  flat silicone coverings, individual fin wingtip, "corrugated" wingtip, and solid wingtip.

Michael Gariffo

The TWS1X buds also include "wingtips," which is what Drop and Grell call their take on small silicone add-ons designed to make their earbuds fit more securely and comfortably in the user's ear. The product includes a total of three sets in various configurations: a solid version, a sort of corrugated option, and one that consists entirely of tiny, individual fins. The solid option provides the most security and most pressure, while the fin-based version reverses those metrics, and the corrugated one is somewhere in the middle. 

A pair of black silicone coverings are also included to fill the slot meant for wingtips, if you'd prefer not to use them at all. 

The only other pack-in found in the 100% paper packaging (props for completely avoiding plastic here) is a short (about 5-inch) USB-C to USB-A charging cable. This compact length definitely limits the charging source options to something like a laptop or tabletop charger, and would be problematic to use with a "wall wart" style charger. 

More: Samsung pledges to remove smartphone plastic packaging by 2025 


The comfort of any pair of earbuds is an extremely subjective matter. Apple's original AirPods, for example, were a torturous experience for me to wear, managing to somehow be both loose enough to consistently fall out and the source of uncomfortable pressure at the same time. Those same earbuds fit several others I know perfectly. The differences in the tiny but unique complications of one's ear mean the same earbud will fit each user quite differently. 

Luckily, the variety of eartips and wingtips included with the TWS1X IEMs mean you have a massive number of possible combinations to choose from. I will say, however, that the size of the earbuds themselves meant they were always a detectable presence in my ear. I was never able to entirely forget I was wearing them the way some smaller competitors have allowed me to. 

More: AirPods Pro review: Noise cancelation and improved design are valuable additions

Of course, this size is necessary to house the quite large (for an earbud) 10mm drivers and the complex audio and active noise cancellation circuitry. 

A configuration using the included medium-sized foam eartips and solid wingtips proved the most comfortable and secure for me when using the earbuds during a workout. The same tips with no wingtips at all proved the most comfortable (if far less secure) setup for casual listening. 

With these wingtips installed, I never once feared the earbuds would shake loose. Without them, these are one of the least secure-feeling truly wireless buds I've used. This means that, if you find all of the wingtip options uncomfortable, you may have a problem using these IEMs for any athletic pursuits. 

The frustrations 

I thought it would be easiest to get all of these issues collected in one place to help you better understand the aforementioned, insanity-inducing aggravations I ran into during my testing. None of these problems completely disqualifies the Drop + Grell TWS1X IEMs from being a great purchase for the right buyer, but their existence remains frustrating. 

These could have easily been the best overall pair of truly wireless earbuds I've ever tested. Even with the issues I'm about to relate, they remain among the best-sounding pairs I've ever used. How close they were to being holistically great is what makes them all the more frustrating. Now, on to the problems I ran into:

  • The reversed positions in the charging case - Obviously, it's possible to get used to this once you've used them for awhile. However, if you, like me, also use other wireless earbuds that didn't mix up their left and right, it gets annoyingly confusing switching back and forth. 

  • Eartips and wingtips fitting in the charging case - The earbuds' charging case definitely could have used a few extra millimeters of tolerance. Not only is there an unpleasant amount of resistance when pushing the buds into the case with any of the larger eartips installed, but I've also had a few times where I removed the earbuds only to realize the eartips had remained stuck in the case from how tightly they fit. This happened most frequently with the larger silicone tips. 

  • Bluetooth connectivity - This is, by far, my biggest issue with these earbuds. Bluetooth has rarely been the most reliable connection protocol. Thankfully, over the course of its five major revisions, it's vastly improved its reliability, compatibility, and stability. Unfortunately, despite running on Bluetooth 5.2, the connection of the TWS1X IEMs was one of the most aggravating I've dealt with in several years.
    First, there were several devices these earbuds flat out refused to connect to. These ranged from a cheap, older, generic USB Bluetooth dongle to a built-in Intel Bluetooth module on a recently-released motherboard. There was no pattern to which supported Bluetooth revision number would or would not connect, either. Another manufacturer's USB Bluetooth dongle running the same revision as the first worked just fine, for example.
    Even when I could get the IEMs to connect initially, keeping them became its own task. Walking out of range of the audio source and walking back into range never resulted in an automatic reconnect. They also suffered occasional, random disconnects. In either scenario, attempting to reconnect them to the device generally required a full re-pairing from scratch to get them up and running.
    More: How to boost your Bluetooth signal to cover your entire home or office
    In a way, the most maddening thing about all these issues is that, if you limit my testing to recently-released Apple devices, you can take every negative thing I said about Bluetooth connectivity and throw it out the window. Their connectivity to both an M1 MacBook Air and an iPhone 13 Pro was essentially flawless. Meanwhile, any type of device from any other manufacturer, new or old, was a crapshoot. 
    It was only during my use of the TWS1X IEMs with these Apple devices that I finally got to experience what these earbuds are truly capable of. That limitation just made it all the more tragic that such incredible sound was being stifled by such problematic connectivity.
    More: Best Bluetooth speakers 2022: Here comes the boom

Drop + Grell earbuds
Michael Gariffo

The sound

I've used the top-end offerings from Jabra, Apple, and many other truly wireless earbud companies. I've only rarely experienced overall sound quality as impressive as what's provided by the Drop + Grell IEMs. I don't think anything else at this price point can match them.

More: Jabra Elite 7 Pro review: Buy for outstanding phone calls, not for ANC

Earbuds are pretty widely expected to have inferior sound when compared to their on-ear or over-the-ear competitors. The diminutive drivers and lower relative power make it difficult to compete with the much larger hardware in over-the-ear pairs. Truly wireless earbuds are often seen as another step below wired earbuds. Their downgraded sound quality is often only considered good enough at higher price points due to the ample convenience they provide in trade.

That said, I've tested earbuds (wireless and wired) and over-the-ear analog headphones that still can't match the sound these earbuds produce. It shouldn't be a complete surprise. After all, Axel Grell worked on not only the HD 6XX and HD 58X Sennheiser collaborations with Drop, but also Sennheiser's own high-end HD 800 Series. 

This may not guarantee that he could design an impressive pair of in-ear monitors. But... he has. 

More: Sennheiser CX True Wireless headset review: Long battery life, affordable price, solid audio quality

On several occasions, I removed the IEMs to make sure I hadn't accidentally left the PC I was using set to output sound from its speakers; that's how roomy the soundstage produced by the Drop + Grell buds could be. Earbuds are notorious for compacting soundstages down to their minimum, but these IEMs gave even the most expansive recordings ample room to breathe. 

This surprising aptitude was further helped by the built-in active noise cancellation (ANC). While I didn't find the included "Noise Annoyance Reduction (NAR) system" to be perceptibly different from the IEMs' standard ANC mode, I did find that built-in ANC to be among the best truly wireless implementations I've ever tested. It easily muted nearly all of the noise from nearby AC units and PC fans, and it greatly dampened more chaotic external annoyances as well.

This enforced quiet helped the earbuds shine as they produced instrument separation so detailed it allowed a level of analytical listening that usually requires a bulky pair of cans to get done. Sparkling highs and deep, rumbly lows were also produced with equal aplomb, far outperforming any other in-ear solution -- regardless of connection method -- I've used at this price point.

Movies and TV shows also flourished when played back over the IEMs, with action scenes proving palpably explosive and quieter moments being replicated with impressive subtlety. 

Some extremely congested music tracks and video scenes sometimes lost a tiny bit of detail, but I'd call it an entirely forgivable amount for any pair of truly wireless earbuds. 

In short, I'd be impressed if a pair of wired, over-the-ear headphones produced this quality of sound at this price point. Hearing that same sound from a pair of truly wireless earbuds was nothing short of shocking. 

Unfortunately, as I mentioned above, I was only able to actually hear it under fairly particular circumstances, mostly with the help of Apple's Bluetooth hardware compensating for the frustratingly unreliable connectivity of the Drop + Grell TWS1X IEMs. 

More: The best cheap Bluetooth headset: Plus speakers!

Wrap up

It should be clear by now this review is a tale of two extremes. 

On the one side, you've got the reasonably priced, truly excellent audio performance of these earbuds. On the other, you've got several shockingly basic design flaws that sour the overall user experience. 

I've used $50 truly wireless earbuds from Anker that could clobber the Drop + Grell IEMs when it comes to simple things like fitting in their case, maintaining a stable connection, and knowing their left from their right. But could those earbuds hold a candle to the sound quality of the Drop + Grell IEMs? Not a chance. And the competition doesn't get much closer when you pit Apple or Jabra's best (with both costing considerably more) against them instead. 

Once again, that's what makes the TWS1X IEMs so maddening. They were so close to being spectacular, but they stumbled on the simplest aspects of their design and operation -- on things that cheaper competition nailed years ago. 

If you primarily listen to your music, videos, or podcast on a late-model iPhone or MacBook, and if you're alright with a far-from-perfect charging case, these earbuds are still worth a look, especially if you've always want a pair of truly wireless options that can actually satisfy your audiophile tastes. 

However, for the majority of shoppers, the Drop + Grell TWS1X IEMs represent too much of a gamble. It doesn't matter how great a pair of earbuds sounds if you can never get them to connect -- or stay connected long enough -- to actually listen to anything. 

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