Aglaya review: the red Demograf Audio tube headphone amplifier

Aglaya is the name its owner gave to a Demograf Audio headphone amplifier on GU-72 tubes, built in a red case. It was made to order: it drives demanding planar headphones, has a front-panel output for electrostatic headphones and speaker terminals at the back. It is not a catalogue model, but a blog reviewer and two forum listeners heard it between 2020 and 2021, with headphones from the HiFiMan HE-6 to handmade and STAX electrostatics. We summarise what they heard.

These impressions are summarised and translated from a published blog review (Club Audio) and from listeners’ posts on an audiophile forum, written in 2020 and 2021. They are the subjective views of their authors, not measurements or claims of Demograf Audio. Aglaya is a one-off build, not a current catalogue model.

The amplifier

Aglaya was ordered with a clear brief: weight, power, ferocity, a rolling dynamic sweep and body. Dmitriy Gubchenko tuned it for handmade electrostatic headphones while listening on the same model of headphones as its owner. According to Club Audio it has enough power for any demanding headphone, including the HiFiMan HE-6, which the review gives as 83.5 dB sensitive at 50 Ω; it also has an electrostatic output on the front panel and terminals for loudspeakers at the back.

What Club Audio heard

In April 2020 the blog Club Audio published a short review of the amplifier under the title “Red is in fashion”.

Sound

• The reviewer calls the sound typical of a tube amplifier: it does not spoil the listener with a wide stage and air, but gives every instrument natural weight and body.
• The sound is dense, driving and juicy, with timbres full of warmth.
• On Igorrr’s Downgrade Desert, when the drums come in, they struck him as powerful and massive yet controlled, with each hit felt in the chest.
• Heavy metal (Exhumed, Kreator, Molotov Solution) played superbly in his view, bass-heavy minimal techno from the Kompakt label sounded excellent, jazz was enjoyable and vocals flowed smoothly.

Caveats

The DAC used for the test was not of a high level, so the reviewer could not judge the amplifier fully, though he found its potential obvious. For classical music he would choose a neutral solid-state amplifier with a wider stage, more air and more fine detail, and he presents this as a matter of taste between a dense, full-bodied tube sound and an airy, neutral transistor one. He also noted the red case, a colour he sees catching on in headphone audio.

With handmade electrostatic headphones

In January 2020 Maxim heard the amplifier with handmade electrostatic headphones from a Chord Hugo 2 and a Krell DAC. He rated these headphones among his five favourites: natural, very even, with positioning he compared to loudspeakers and a technical level close to the top STAX models.

• The amplifier itself gave a fairly transparent, voluminous sound with moderate warmth, plus power, good dynamics, a very deep stage and a powerful, full upper bass and lower midrange.
• With these headphones the result was well balanced and correct, with a slightly darkened overall tone that came from the headphones.
• What struck him was the combination of power, ferocity and weight with transparency and space: hits were whip-like and clear rather than merely aggressive, with very good separation and positioning. For metal, he wrote, he could not imagine anything better; from here, only the DAC and cables were left to tune.

After an upgrade

In December 2020 another listener heard the amplifier with handmade electrostatic headphones and a Demograf Audio DAC after it had been upgraded. In early sessions he had found it dark and dense; now the sound had cleared, with a calm, neutral and finely detailed midrange. He found it so natural that he stopped looking for hi-fi effects and simply listened to the music.

He compared it with a STAX SRM-006t hybrid energiser on the same headphones. On the STAX unit the headphones lost body and bass and, for him, interest; he admits he is no fan of the STAX sound, and preferred the tube amplifier.

Next to the Tantal

In April 2021 the same listener heard the red amplifier and its DAC alongside a Tantal. After servicing and further work the red pair had become more detailed, neutral and technical, but had lost some massiveness; after the Tantal and another Demograf Audio system it sounded simpler. With STAX electrostatic headphones he found it an excellent match. Comparing several versions of the handmade headphones with STAX on the red amplifier, he heard them ahead only in the size of the imagined stage and in larger images.

Reported limits

• Club Audio found the stage less wide and airy than a good solid-state amplifier’s, and would choose differently for classical music.
• Its first voicing was dark and dense for some listeners; after the upgrade it became more neutral but lost some weight.
• Next to the Tantal it sounded simpler.

Summary

Aglaya was voiced for weight and power with handmade electrostatic headphones, and listeners heard exactly that: a dense, warm, driving sound that carries heavy metal, electronic music and jazz, with a deep stage and enough power for the HiFiMan HE-6. Its later, more neutral voicing traded some of that weight for clarity. As a one-off build it shows how far a Demograf Audio amplifier can be tuned to one owner’s brief.

Which Demograf Audio piece fits

Aglaya is not in the catalogue. The current amplifiers closest to it are these:

• Tantal, on 3C24 triodes, 3 W per channel, with a STAX-type electrostatic output built in and speaker terminals.
• Helios MkII, on G-811 triodes, 15 W per channel, with headroom aimed at hard-to-drive headphones such as the HiFiMan HE-6; an electrostatic output is an option.
• Tantal Senior, on 4E27 pentodes, 30 W per channel, with a STAX output as an option.

Every amplifier is made to order by Dmitriy Gubchenko, with a one-year warranty (extra warranty available: +1 or +2 years), and the voicing is agreed with you before the build. Our headphone amplifiers page lists every model, and owners compare the Tantal with the Viva Solista and the Sennheiser HEV 90 in our Tantal comparison.