Name: Grell Audio TWS/1
Brand: Grell Audio

STEREO GUIDE verdict

91%

91%

Highlight

+ very natural tonal balance
+ excellent resolution and transparency
+ very rich, clean bass
+ useful ANC with transparency mode
+ SoundID app with individual sound adjustment
- Gesture control necessarily intuitive
- not as easy to insert

Sound: Tonal Balance / Transparency
9.2
Sound: Bass / Dynamics
9.1
Ease-of-use / connectivity
8.2
Price/Performace
9.8

Remember Sennheiser´s HE 1? These most expensive headphones in the world? The company being famous for models like HD 580, HD 600, HD 650 or HD 800 has made legend. In the meantime, Alex Grell, the chief developer of the HE 1 electrostatic 60k headphones, has left for a new goal: making top class earphones affordable. His company, Grell Audio, as a first step launched the Grell Audio TWS/1 – a true wireless in-ear with active noise cancelling (ANC). At 200 bucks, these Bluetooth-only earbuds not only offer high end sound quality, they give a pretty solid impression. The charging case and both earbuds weighing a reasonable 7.3 grams each, are made of aluminium.

Take a left for a right: not the way you are used to things

The design is idiosyncratic and so the product is guaranteed to be recognised easily. However, inserting the earbuds with an elaborate twist is not exactly intuitive. There is an unconventional shape. Grell has designed the case, being equipped with some feedback LEDs, the reverse way soright and left have to be swapped. Those who don’t look closely at their new earphones on the first try, or even suffer from visual impairment, will probably poke around with the two Grells in their ears at first, being left perplexed.

Enabling bluetooth and establishing connecting pairing were also calling for some patience. Okay we have to keep in mind that our test sample was an early beta unit. And they had already been reviewed by other journalists before reaching e Stereo Guide, so had undergone a pairing procedure with a different phone kind of sticking to that one. Obviously the hard reset, precisely following the FAQs on the manufacturer’s homepage, led to nowhere.

We need gestures to control this thing

For fully controlling the TWS/1 by touch gestures on the glass surfaces it is worth taking a look at the user manual and practice a bit before really taking them to a field testing. The earbuds are promised to offer a battery runtime of 30 hours, including recharging in the case and activating ANC. Up to 10 additional hours may result in deactivating ANC. However, this impressive battery life is not really to be achieved under everyday conditions. We would say it is rather up to 8, in practice rather 5 to 6 hours without recharding. The case offering an additional capacity of 4 full charges.

Review: Grell Audio SoundID App: Update — Updates are downloaded via Sonarworks SoundID app. Firmware 2.7.0 solves problems with battery self-discharge. (Photo: Stefan Schickedanz)

Review: Grell Audio SoundID App: My Sound — Updates are downloaded via Sonarworks SoundID app. Firmware 2.7.0 solves problems with battery self-discharge. (Photo: Stefan Schickedanz)

Firmware update no. 2.7.0 prevents problems of self-discharging

Inital reviewing, however, were showing batteries in both case and earphones being always discharged when put aside for a few days. With the help of firmware update 2.7.0, downloaded via SoundID app and uploaded to the TWS/1, this problem is vanishing. Reason being that previous firmware versions did fail to shut down the earbuds properly.

The Grell Audio TWS/1 is suitable for Sonarworks´ SoundID app, which is available free of charge for iOS and Android. The enables the creation of an individual listening profile with a series of A/B comparison tests. Like the sine test samples of Jabra´s Elite 7 Pro app, this does not aim to create a listening sensitivity response curve like a medicinical hearing test would. Sonarworks rather takes into account the owner’s taste and preferences for individual equalization (it is later preset within the earbuds and can be run without using the app). This may add some brilliance or more bass. There is also a powerful equalizer to manually adjust the tonal balance in the recording engineer´s way. This whole procedure works very well and underlines the convincing overall concept of the Grells.

Ready to talk

You can also answer phone calls using the Grell TWS/1’s integrated mic array – with quite decent speech quality. An alternative voice-through mode can be activated, to follow announcements in plane or train for example. Because significant noise supression in the low frequency range might cause higher frequencies to be perceived predominantly at the same time, the developer came up with something new. The patent-pending Axel Grell Noise Annoyance Reduction technology (NAR) is permanently analyzing the complete noise spectrum and adjusting the ANC circuitry according to psychoacoustic findings. As a result, unpleasant distortion of tonal balance should be avoided and not affect the listening pleasure.

XL Driver

Even though the large diameter of the earbuds is helping touch operation, the primary reason for chosing such a size were the exceptionally large dynamic transducers offering diaphragms of 10.1 mm in diameter. These custom-made for Grell drivers favor the accurate reproduction of deep bass with decent SPL handling. Axel Grell was also generous when it came to audio codecs. In addition to the standard SBC codec, the TWS/1 support AAC, aptX, aptX adaptive, and LHDC. At the same time, the Grell Audio allow quite some distance to the wireless audio device, which can be very convenient, especially in home listening environment. However, the 50 meters stated by the manufacturer can only be reached in open field – which is just of theoretical significance. If walls are taking into account, the wireless range is reduced to a value that still promises very decent freedom of movement.

Reviewed by STEREO GUIDE: The two TWS/1 — The Grell Audio TWS/1s turn out quite large due to their 10 mm drivers and are somewhat awkward to insert into the ear canal. (Photo: Stefan Schickjedanz)

Tested by STEREO GUIDE: Grell Audio earphone charging case — The Grell Audio TWS/1s turn out quite large due to their 10 mm drivers and are somewhat awkward to insert into the ear canal. (Photo: Stefan Schickjedanz)

Rich and natural sound

The listening test of the Grell Audio TWS/01 revealed a nearly perfect tonal balance and quite some drive combined with rich, clean bass that might move your to the rhythm almost immediately. With every note one could experience the extraordinary sense for voicing plus a vast experience of Sennheiser´s former developer. His first earphones deliver a more than solid performance in every respect. But they stand out not only by exemplary tonal balance.

However, the feeling of listening to something really natural was by no means only the case in the world of timbres, which also predestined the TWS/1 for classical and jazz music offering a lot of natural instruments and multi-layered vocals. We also enjoyed the combination of silky transparency and high resolution that contributed to the extremely appealing listening experience. We also liked the wide soundstage by in-ear standards. The comfortable fit also contributed to the fact that you could listen to the Grell for a long time without listening fatigue.

Better opt for Grell Audio´s TWS/1 or competitors?

Grell Audio´s premier product is showing his own way in terms of design, pricing and features. A rock-solid true wireless in-ear with active noise cancelling, individual voicing via the Sonarworks app and very decent battery life for 200 euros from a German brand – you don’t get such an offer every day. What might contribute to this bargain value-for-money, following a general trend in mobile hi-fi, Grell relies exclusively on direct sales with no retail margin.

An alternative would be the equally bass-rich Jabra Elite 7 Pro offering decent ANC as well and boasting with even more features included in the designated app. They are also easier to operate and insert into the ear canal, being a bit lighter and even more comfortable. However, just the overall voicing and tonal balance of the Jabra did not quite meet the naturalness and audiophile standards that distinguish the Grell Audio TWS/1.