This module allows the Deva Pro to become a “Bluetooth” pair of headphones, since the Bluetooth electronics are all inside the module instead of the headphones. I am not going to go into the packaging and presentation in much depth as I have already covered it multiple times in previous Hifiman reviews, so I will just say that there are no complaints from me as far as packaging. It offered a very pleasant, musical, and smooth tone while keeping that signature Hifiman technical performance. Obviously these are not a set of bluetooth headphones that you would use on a plane or other transport, but the commodity of being wireless whenever needed, without a loss of quality, is something to be praised.

One potential use-case could be having them as an all-in-one solution, but then you are sacrificing the lifestyle features of the best wireless headphones and the sound quality of the best wired headphones. However, what distinguishes them is that in addition to the possibility of a wired connection with a classic cable, a great bletooth adapter based on the R2R bluemini architecture with the original HIFIMAN chip is included. The design and workmanship refer to the he-400se model, but the Deva pro earmuffs are a bit thinner. I would have liked them to include some kind of storage/transport case, as Bluetooth headphones are usually something that are aimed to be portable (or at least transportable), but that is more of a wish than a complaint. The pads and the headband are both quite plush and soft, and I’m not having any problems with wearing them for a couple of hours.The competitors are just left in the dust, and by a margin so big, that simply makes the Deva Pro one of the best audio products currently available on the market.

The Questyle CMA-400i and Macbook Pro were used for wired listening, and Pixel 4XL was used for wireless listening.This means that you can effortlessly use this HiFiMAN Deva with your smartphone, hi-fi amplifier or with a premium Hi-Res music player for the best possible sound experience. The tuning is balanced with neutral bass response, linear mids and a little bright but smooth and controlled treble. As for emphasis the treble part is a bit more forward than the rest making for a sparkly and livelier presentation, giving instruments more illumination this time. Seeing that the R2R version of the Bluemini is replacing the old one in all current bundles speaks of HIFIMAN’s confidence about its sound and indeed it proves to be a more refined, more organic and grippy listen with better timbre.

In BT mode there is more emphasis near the sub-bass it seems, though the bass sounds rolled-off after 35Hz in all three modes (Bluetooth, USB, and wired). To connect to the source for the first time, you switch on the module (hold the button for a couple of seconds) and once it is on, press the button twice to enter pairing mode. At the beginning of 2021, I had the chance to review the Ananda Bluetooth, a more expensive set of Bluetooth headphones from the brand. I imagine that the goal with the Deva is to be somewhat of a proof of concept - that you can in fact have audiophile level sound quality with the convenience of a wireless design.Instruments such as the piano and the guitars sound rich and luscious, creating a relaxing ambience. Perhaps this makes things sharper and clearer -- but it really lacks any soundstage, and that's one of Hifiman's signature things. Their open-back nature make them unsuitable for commuting, though, and the low clamp force is not ideal when wearing them during physical activities. Deva pro is a slightly lighter, more open and organic approach to the subject, with less bass and more air.

It is good and straight to the point, and most importantly – the box is secure enough that you don’t have to worry about the safety of your new headphones while in transit. I don't have your current iems but the EQ should add some more bass, at least in quantity/tonality because quality will remain the same. I think the nitpicks I’ve pointed out here may all add up to something when you compare it with the Sundara or Sennheiser HD6XX, but on the whole it’s easily still a good sounding headphone.Back to the sound though, the amount of details, crispy yet ringing little sounds coming from different places make this song a fantastic showcase piece to test equipment on, and the Deva Pro performs like a champ here. Just listen to the Messa da Requiem by Verdi with the huge instrumental and choral forces to get a feeling of the soundstaging capabilities of the Deva Pro. Even if you consider just the headphones themselves only a 4/5 in terms of quality (which I’d still argue isn’t particularly fair/accurate, but it’s definitely way, WAAAAAAY less so), this is EASILY a 4. On that note, instrument separation is still very good with the Deva, and I generally find this to be one of the advantages of planar magnetic headphones. It’s not noticeable on many recordings, but for some of my test tracks like from Patricia Barber for example, this starts to get noticeable.