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EPOS ADAPT 660 - a UC, BT, ANC headset from Sennheiser
5.0Overall Score
Name: EPOS ADAPT 660 BT, ANC headset from Sennheiser
Price (RRP): $640 but shop around
Manufacturer: EPOS

The EPOS ADAPT 660 BT, ANC headset is Sennheiser’s design for premium UC (unified communications) use. It is also a damned good BT, ANC over-the-ear headphone as well.

The EPOS ADAPT 660 BT, ANC is based on our favourite Sennheiser travel headphone – the ultralight 227g PXC-550 II with some tweaks for business UC use.

BTW EPOS is the new name for Sennheiser’s UC and Gaming divisions (GadgetGuy announcement here), so it has a 75-year sound heritage that is very hard to beat. You will see more of EPOS as a brand but remember it is from one of the best.

And don’t be put off by the term UC – it simply means that you need the best possible sound to deal with remote customers.

EPOS ads its secret sauce – EPOS AI to the PXC-550 II so we will try to show the differences.

Australian review: EPOS ADAPT 660 BT, ANC headset

  • Australian website here
  • Price: $640 but shop around
  • From: Authorised dealers but also check online as you may bag a bargain. Beware online may not come with ACL warranty.
  • Warranty: 2-years ACL and covers commercial use (no consumer brands/models do not cover this)
  • Country of manufacture: China
  • EPOS is the commercial division of Sennheiser. Its products have Danish design. It has solutions for call centres, business and more.

We use the terms FAIL, PASS and EXCEED against all review parameters for this type of device.

What is the EPOS ADAPT 660?


Over-the-ear, Bluetooth 5.0, Adaptive Noise Cancelling headphones with up to 30-hour battery. Its base is the excellent Sennheiser PXC-550 II.

The key difference is that it is UC Certified. That means it works with almost all teleconference apps and even has a ‘purple’ button to initiate (among several things) a Microsoft Teams session, place a call and record it.  At present, the purple button is MS Teams specific, but I understand that an app will adapt it for Zoom, Webex, Skype etc.

It comes with a USB BT dongle BTD 800 in case your UC device does not have it. The theoretical range is 25 metres but if you wander around the office limit that to about 10 metres.

It has a 1.2m USB-A to micro-USB cable and a 1.4m 3.5-2.5mm audio cable. The pièce de resistance is that it all folds down into a compact hard-sided carry case.


BTW – It is one of the few headsets (headphones) that has a built-in USB DAC. What that means is that it can charge via USB and play music at the same time. Not even or Sony reference WH-1000xM4 can do that. It is reason enough to buy Sennheiser headphones.


EPOS says its AI is for crystal clear calls, adaptive ANC and superior stereo sound. Adaptive ANC means it monitors outside noise and adjusts noise reduction as needed. It also reduces wind noise.

What we can find is that it has three AI voice mics and four ANC mics. That is seven – quite a lot.

There is a white paper on EPOS AI here (it is a PDF so check downloads folder) but here is a summary

  • Machine learning identifies use, voice and noise patterns. It can extract voice from the other noises like ringing phones, chatter, traffic, barking dogs and much more.
  • The hard yards are put in at the EPOS sound lab and downloaded to the headset with firmware updates.
  • It also runs on the headset – AI at the edge. It can discriminate between your voice and the callers – both sides of the call

We were able to test both the PXC-550 II and the ADAPT 660, and you can hear the difference in UC use. The ADAPT has several levels more ‘quietness’ and better mic pickup, but we will come to the one trade-off later.