Denon AH-C840NCW True Wireless Headphones, ANC

The Denon AH-C840NCW is a True Wireless in-ear headphone with Adaptive Hybrid ANC, combining Denon's newer bio-cellulose drivers with long battery life.

It's the 2025 generation of Denon's ANC earbuds: the same goal as the AH-C830NCW – peace on the go, good sound – but with a newer driver, a more modern Bluetooth codec and significantly more battery life.

Why the AH-C840NCW?

A 12 mm bio-cellulose driver with a free-edge suspension delivers a clear, controlled sound. Adaptive Hybrid Noise Cancelling continually adjusts to your surroundings, and there's a transparency mode for conversations on the go too. Bluetooth 5.3 with AAC, SBC and the newer LC3 codec ensures a stable connection and supports Auracast as well as multipoint – keeping two devices paired at once.

The wirelessly chargeable case and the range of ear tip sizes (S, Long S, M, L) provide an individual, secure fit.

What you hear

A clear, balanced sound with a good bass foundation – the bio-cellulose driver resolves more finely than older Denon earbuds in this price class. With ANC activated, your surroundings become noticeably quieter, without the music sounding thin.

Who is the AH-C840NCW for?

For anyone looking for a modern, everyday-ready ANC earbud with long battery life – commuters, travellers, home office with lots of calls. Straight talk: if you want absolute reference sound and lossless aptX Lossless, you'll find that in the more expensive PerL Pro. IPX4 means sweat and splashes are fine, swimming isn't.

Our verdict

The AH-C840NCW is Denon's well-rounded everyday model: good sound, reliable ANC, modern connectivity and battery life that even survives long travel days. For most everyday demands, that's completely enough. At HD Zürisee in Wädenswil, we're happy to advise you on whether this or a PerL model suits you better.

Technical data

• Type: True Wireless in-ear headphones with active noise cancelling
• Driver: 12 mm, bio-cellulose, free-edge
• Bluetooth: 5.3
• Codecs: AAC, SBC, LC3 (Auracast-capable)
• Noise cancelling: Adaptive Hybrid ANC, with transparency mode
• Earbud battery life: up to 10 hrs (ANC off), up to 7 hrs (ANC on)
• Battery life with charging case: up to 35 hrs (ANC off), up to 24 hrs (ANC on)
• Charging: USB-C as well as wireless, charging case fully charged in approx. 2 hrs
• Protection rating: IPX4 (earbuds)
• Weight: 5.1 g per earbud, charging case 54 g
• Included: left and right earbuds, wirelessly chargeable charging case, USB-C charging cable, ear tips in several sizes (S, Long S, M, L)

Frequently asked questions

Does the AH-C840NCW support Auracast?

Yes. Via Bluetooth 5.3 with the LC3 codec, the AH-C840NCW is Auracast-capable – you can tap into public Auracast broadcasts in the future, for example at the airport or the gym, wherever the venue offers it. It also supports multipoint for two devices connected at the same time.

How long does the battery last on the AH-C840NCW?

With ANC switched off, you get up to 10 hours directly in the earbuds, and up to 35 hours together with the charging case. With ANC active, that's 7 and 24 hours respectively – enough for most travel days without a top-up.

Why buy the Denon AH-C840NCW at HD Zürisee?

Because we show you which Denon model really suits your everyday life, instead of automatically recommending the most expensive one. HD Zürisee in Wädenswil advises you personally – call, message us on WhatsApp or drop by with your question.

Goes well with

More headphones from Denon and matching accessories such as replacement ear tips.