Audiophilepure

https://www.whathifi.com/hi-fi/headphone-amplifiers/sennheisers-versatile-hdv-820-headphone-amp-dac-boasts-a-monster-gbp600-saving

The Sennheiser ticks plenty of boxes in terms of connectivity. Unusually, there’s a traditional 6.3mm jack integrated into the three-pin XLR socket on the front of the unit.

You also get a four-pin XLR and a pair of 4.4mm Pentaconn jacks on the front, both of which allow a balanced connection to suitable headphones.

Another string to the HDV 820’s bow is that it can also act as a preamp thanks to the presence of both single-ended and balanced analogue inputs and outputs, plus a separate gain adjustment to fine-tune the output for your power amp or active speakers.

The DAC functionality comes via a trio of USB, coax and optical digital inputs, with resolution limits of DSD256 and 32-bit/384kHz for PCM music files.

Add solid build quality and a great user experience to the mix, and you have a versatile amp with plenty going for it, not least a £600 discount over at Scan.

https://www.stereophile.com/content/gramophone-dreams-98-woo-wa24-headphone-amplifier-lyra-hana-phono-cartridges

The careful crafting of Barbara’s suave elocution dominated my attention, presenting well the shifting textures and moody vicissitudes of the artist’s delivery. Sound quality felt irreproachable.
Next, I tried Barbara with the closed-back ZMF through the Woo WA24. I was greeted by a sweet liquidity of tone that felt so luxurious that Barbara was no longer an element in a studio recording. Now, she was a woman, with a face and body and an accessible persona. Except for a sense of awe, my critical mind was silenced by the allure of Barbara singing the album’s title song: “Dis, quand reviendras-tu?”
This was the moment when all the WA24’s tube magic came out. I felt like I was hearing this record like no one had ever heard it before. The form and quality of tube beauty that dominated the WA24-Vérité presentation exceeded any tube beauties I’d previously experienced.

During the past weeks I have used the Lyre as my main headphone amplifier, driving my HE1000SE, my Arya Unveiled and the Palma DH-S1. It was mostly connected to my Hugo TT2 as DAC via the XLR inputs. The Lyre also stepped into my main stereo speaker system as a pre-amplifier to test the pre-amp functionality.

The Auris amp was powered by my AudioQuest PowerQuest 707 and cabled with AudioQuest’s Black Beauty cables.

The Lyre has a traditionally beautiful and rich tube sound, which oozes of analogue warmth and an organic body. It is a more neutral presentation overall, but features impressively natural sound in the mids, where instruments and singers just sound right out perfect to me. Lyre has excellent staging and delivers exceptional results especially in layering and depth to me.

Another highlight is the LEDs surrounding the unit. These LED lights illuminate during use and serve as indicators for volume and even navigation assistance. It’s a flamboyant decision since many gamers like to play in dimly lit or dark rooms, and these lights aren’t exactly subtle.

That said, there’s a feature that allows you to turn them off. In well-lit environments, LEDs are not overwhelming, and I kind of  like them. They look very “cyberpunk” combined with the naked internals.

On top of the unit are three buttons: a red button on the right for menu selection and two black buttons for volume up and down. They are tactile enough, though the feel is closer to a soft click than a mechanical press.

These buttons handle filter switching, output mode selection, USB UAC mode, filter selection, and MQA mode without the need for an app. The “menu” is actually on the bottom side of the transparent top panel.

You get assistive LEDs to know what’s what. The usage is simple, although the labeling is hard to read due to the small font size.

https://pt.audio/2025/06/08/atma-sphere-gem-integrated-headphone-amplifier-review/

What I have here is a really tiny amplifier. Actually, it’s way more than that; this gem really does duty as an integrated amplifier that can handle both efficient speakers and a bevy of headphones, ranging from the efficient to the not-so efficient. I’m not really much of a headphone guy, so I employed this Gem as an amplifier for my really efficient Charney Audio Maestro-X single-driver speakers.

A bit of history about Atma-Sphere first. Ralph is best known in the industry for pioneering two things: output transformer-less (OTL) vacuum tube amps and use of fully balanced circuitry and connections in his amp and preamp products, and these design elements are highlighted in his mainline designs to this day. Interestingly, the Gem (on the surface… see below) sports neither. Right on top are exposed output transformers, and a quick look at the rear panel indicates the presence of (only) single-ended RCA input jacks. Was Mr. Karsten perhaps being a bit contrarian here with this design?

The following sound impressions were made after 100 hours of burn-in for the stock tubes. I used the FiiO JM21 and HiBy R4 as DAPs, the Oppo BDP-83 as a CD transport, my MacBook Pro as an alternative, and the Soundcraft Absolute 4P powered speakers for XLR-balanced out.

Listening devices included the SJY Horizon, Kennerton Rognir, AKG 240DF headphones, Campfire Audio Supermoon, Solaris 2020, and Drop x Campfire Audio Dark Star IEMs. The 4Ps were used for balanced output, and my McIntosh MA6100 as a power amplifier (aux-in), and pre-amp in.