Grell TWS/1

Here we have a HiFi review of these Grell TWS/1 in-ear monitors, the first product from Sennheiser legend Axel Grell.  At £179.99 ($199) these are in that mid to high premium Airpod space and these days,

for this sort of money, we are expecting good things.

Design

These Grell TWS/1 in-ear monitors feature a full range 10.1mm dynamic driver with a decent dynamic range of a claimed 4Hz-22Hz, we’re not likely to hear much more than that anyway, by all accounts.

The Grell TWS/1 in-ear monitors have a stem on the earbud with a custom matched microphone.  The Grell TWS/1 in-ear monitors feature Active Noise Cancellation from Qualcomm as well as what is described as Grell’s Noise Annoyance Reduction (NAR) which apparently takes out the high mid and high annoyances that may impact the listener’s enjoyment.  There is a Transparency mode that you can switch to that allows ambient noise.

Connectivity in the Grell TWS/1 is through Bluetooth 5.2 with a Qualcomm 5141 chipset.  The range is quoted at 50m.  The TWS/1 support Qualcomm’s aptX and aptX adaptive.

There is an aluminium charging case that has the earbuds, left and right are the wrong way round for some reason, but you only get this confused once.  The case has wireless charging and offers four charging cycles using the internal battery. The claimed battery life is up to 28 hours battery with the charging case (ANC on).

The Grell TWS/1 are compatible with the SoundID App, which offers a tailored frequency response to the listener through an App.

Quality

The buds are really nicely presented, and they feature a large round Gorilla Glass pad on the outside that facilitates touch control, there is the usual array of rubber or silicone buds of different sizes to fit your ears. The Grell TWS/1 in-ear monitors come in minimal packaging which is definitely environmentally friendly.

Each bud weighs in at 7.3g each, they come in space grey, and there is a black limited edition TWS/1X available exclusively to US customers on  The Drop.  I note the US version has a ‘felangie’ (see Physical comments below), called a wingtip, in blue. I wish that was available in the UK to this reviewer.

The Grell TWS/1 are available in the UK on The Grell website at £179.99 (May ’22).

Performance

Review Equipment

I’m listening to the Grell TWS/1 exclusively with my Pixel 4 XL Android smartphone with either the Qobuz App or Tidal.  I also have 24-bit tracks downloaded on it where I use PowerAmp.  As you will read, I’m using the SoundID App to customise the Grell TWS/1 sound to my ears, a bit like the Mojo2 DSP tinkering that you just have to embrace.

Physically

At the outset I will say I have no issues at all with pairing, setting up, etc.  I have had a bit of trouble keeping these Grell TWS/1 in my ears if truth be told but a change of tips to the silicone spares that are in the box and a good lick (which is a good idea anyway to create a good seal) has latterly proved to secure the Grells in place relatively reliably.  There is obviously some kind of pressure release system in here, presumably through the microphone stems as there is no eardrum pressure when you press them into your ears, this is great.

I feel, physically, these Grell TWS/1 are too heavy for my ears, I realise there is not much that can be done about this, but it feels like they need a ‘felangie’ (see Friends S10) or something to connect them or press them to the outer ear, like the JBLs I used to use, or the Lindy LTS-50s I spend a lot of time with these days on the rowing machine.  I am simply unable to use the Grell TWS/1s on the rowing machine which is a shame because I need music to relieve the pain.

Another physical comment is these Grell TWS/1 do stick out a fair bit and they are not great performers for me in the wind.  There’s too much whistling whether you have ANC or Transparent on, this is not so great.

Finally, the toggling of the features on each Earpad is excellent and after a bit of fiddly learning, it becomes very intuitive.  On the left bud, you can toggle ANC, NAR, and Transparent mode seamlessly with a soft notification beep.  On the right bud you can control volume, skip tracks, pause, and speak to, in my case, Google’s Assistant (it does Siri, Cortana, Alexa and Bixby too).

A Game of Two Halves

On the sonic side, these Grell TWS/1 IEMs have been a game of two halves.  However, it does serve to show as a reviewer you do need to give products a good listen and keep an open mind.

It is worth noting these headphones have come off the back of this reviewer using the Chord Mojo2 with a pair of Meze RAI Solos, a wonderful, HiRes portable sound, probably the best you can get on the move (would be better with the RAI Pentas of course).  To start with I was really struggling with these buds, they were sounding a bit thin, kept falling out because they were too heavy, and they were also annoyingly sensitive on the touchpads.

BUT, with perseverance and the SoundID App, I’m all in, these guys are great, well really good at least.

SoundID

I have stumbled across the SoundID App, by a company called Sonarworks, in truth whilst browsing the Grell TWS/1 site for technical data, the QuickStart instructions make no reference to SoundID, and yet it is the game-changer.

SoundID is a universal custom sound App that you can use to tune your ears to a pair of headphones. It seems to offer this custom tuning for many brands, including AKG, Apple, Beyerdynamic, B&W, Focal, Meze and, needless to say, Sennheiser.  I guess you can describe it as a custom graphic equaliser in an App.

The SoundID was very easy to set up in Android.  The download offered a firmware update (2.7.0) for the Grell TWS/1 IEMs which took 3 minutes or so, after a validation and reboot process.  This is great news and shows the Grell TWS/1 IEMs are actively supported at this time.  After this, there was the custom tuning option, where you are played several tracks (electronic, rock, acoustic) and you select your preferred frequency outcome, A, B, or D in most cases.  You only do this once, thereafter, this sound profile can then be toggled on or off in the App when the Grell TWS/1 IEMs are in use.  On a daily basis, I sync the SoundID App up after firing up Tidal and turn on the SoundID, depending on what I’m listening to.

Resolution

In my view, these IEMs can be simply characterised, sonically, by their attention to detail and an excellent midrange and energetic presentation that doesn’t seem to need too much driving.

If I take The Staves’ live arrangement of Ray LaMontagne’s Jolene (Tidal 24-bit, 88.2kHz), the guitar in the midrange is crystal clear and you can pick out the individual vocals in the harmonies.  The same clean detail happens with Amos Lee’s wonderful track Keep It Loose, Keep It Tight (Tidal 16-bit, 44.1kHz).  Ben Howard’s Everything (Tidal 16-bit, 44,1kHz) on his debut album Every Kingdom has a huge amount of detail and the fingerwork with the strings is captivating.  For me, these tracks are really benefitting from the SoundID App that I have tuned to my ears.  The App seems to be filling in the background gaps and lifting the soundstage up a level.

In respect of the ANC, this really does a great job of isolating you from the outside world, if that’s what you need.  I have to say on occasion SoundID does really close in on you and thicken up the presentation in a good way but if I’m listening to, say Led Zeppelin II, I really need to turn off SoundID because the low end is a bit much, but maybe that’s the way I tuned my App up?  With the jazzy vocal stuff (Etta James, Sarah Vaughn, Ella, etc.) the vocal and the music benefit from turning the SoundID off, to liberate the upper midrange up detail you may be searching for with maybe that snare in the midrange or delicate cymbals in the upper midranges.  I must add this may be a function of my custom tuning profile, but the key takeaway is these Grells are very flexible in output and have terrific resolution.

Microphones

I’ve been recording a few videos and doing commentary with these Grells; the mics seem to be very clear and a ‘staged’ phone call I had with them was reported to be very clear by my ‘counterpart’.

Battery wise

Because I tend to charge the case on the wireless charger during the night in the usual corner, I’ve had no battery issues but have little reason to doubt the quoted lives based on my listening levels, not much help, but the quoted hours are on their website.

Final Thoughts

There are a few oddities here, the charging case has the buds the wrong way round, I’m sure there’s a reason for it.  The other good news for me is they can be used with one ear in, one in the case.  ‘Monomode’.  This suits me for gardening and washing the car purposes if I’m listening to a radio broadcast but need an ear out for other things.  On that note, they are splashproof to IPX4 specification.

Overall

These are a fine pair of headphones with a few initial quirks but after an extended period, they have delivered consistent and solid performance, particularly in the midrange, with clarity and resolution.  I feel the ANC is fine and they are easily controlled after a bit of getting used to the control system, which is very intuitive.  Connectivity has been excellent and battery life appears to be significant.

Specification

Full details are on the company’s site