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If I had to gripe I’d point at a sonic character slightly too lightweight. Bass was well controlled and resolved but there was too little of it in connection with the HD800. And with Depeche Mode Ultra Freddie Hubbard’s "Open Sesame" wasn't properly anchored. On a side note, wanting to save dosh by going after a cheaper Taiwanese Collector’s Edition I was fooled. It’s merely a CD, not hybrid SACD. And it was pressed in the Polish Takt factory without a plastic cover. Back on track. The same lightness in the lower midrange was apparent on Jim Hall’s Live! His guitar was well defined in space as a clear strength of the ADL and in terms of textures brilliantly resolved. It simply was not as extended as it should have been. That’s when I swapped headphones. As it turned out HifiMan’s HE-4 were excellent partners which lowered the tonal balance but maintained their brilliant treble clarity. Now the midrange filled out to become more three-dimensional. A new issue cropped up however in the HE-4’s low efficiency. On most material I was okay but on quieter CDs like Jim Hall’s only opening the volume control fully netted satisfactory loudness. This then also introduced compression and clipping.

As previously with HifiMan’s own EF-5 amp, the golden middle turned out to be AKG’s K701. This does not imply that other headphones won’t perform equally well. The amp simply prefers low-impedance higher-efficiency loads. It neither fancies 300/600Ω like my Sennheisers or Beyerdynamic’s DT990 Pro or low-efficiency designs. With the AKG I had a very good tonal balance and a nicely saturated lower midrange. Here too the amp’s strong treble remained evident but it was not disturbing since the AKG rounds it off a little to make for a splendid combination.

As line preamp: Here surprise collided with deep respect. Replacing an 80.000zł dedicated preamplifier with an upstart 1.900zł multi tasker usually invites problem but not here. While the Furutech was clearly inferior on resolution, dynamics and dimensionality, it still served the sound in such a way as to not hurt. Most of all it maintained the same tonal balance as my usual Ayon Polaris III for a slightly warm fleshy timbre. Without imitating valves there were certain similarities. Even more surprising was the very potent low bass. Such articulated double bass with real kick in its lower reaches I’d not heard in a long time regardless of price. And the Japanese mini had truly terrific dynamics too. From this point forward the GT40 is my new reference preamp recommendation below 10.000zł, period. Where the best tube units at this price beat the ADL is scale. Here everything was slightly smaller and condensed towards the central listening axis. This was not bad—again the ADL is really a quite wonderful little preamplifier—but a good tube preamp of about 10.000zł will have grander breath and scale to get closer to the live event. But considering price, a loud bravo is in order!

As USB DAC with variable outputs: The built-in USB DAC is characterized by subjectively high resolution where differences between 16 and 24 bits or 44.1 and 96kHz were clear. Denser files were calmer and had better timbre. With CD-quality files the ADL accented the treble which won’t work well with all power amplifiers and loudspeakers. This is a clean precise sound but 24/96 files were far more relaxed and also had superior midrange and bass. The latter was solid and forceful but with CD not as substantial as it had been in preamp mode. However one turns it, this is a good DAC, period. It is not as saturated and ‘analogue’ as the KingRex UD-1 Pro had been but upper midrange and treble were better differentiated and crystallized especially with 24/96 material.

As phonostage: Although many will regard this instinctively as a mere convenience feature, in my opinion the GT40 could justify its sticker on analog alone, i.e. with its phono and linestage performance. Obviously here one cannot separate those two. The phono function nicely complemented the preamp sonics with a similar flavor. I mostly spun vinyl with my Denon DL103SA MC cartridge as reference. This was mounted to a Music Hall MMF2.2WH table. It resulted in a strong dark sound with lovely timbres.

Resolution was nearly overwhelming but without any bad aftertaste. For the money it simply cannot be bettered. With a more expensive deck like Transrotor’s Rondino the sound opened up further and resolution still improved further. I do not think that owners of the Rondino would look at the GT40 but you should know that such a combination would not be as much of a misalliance as you might assume.