Aphrodite (TDA1547) DAC: owners’ reviews

Owners of Demograf Audio converters on the Philips TDA1547, the vintage DAC chip now offered as Aphrodite in the Reference Tube DAC, describe a fast, detailed and dynamic sound with a full low end, a striking midrange and a closeness to vinyl. Below we summarise their posts from 2011 to 2013: the sound by range, what they heard on CDs against vinyl, how they compared it with a Berkeley Alpha DAC, a Mytek DAC, a Weiss DAC202 and other chips, and what they warn about.

These impressions are summarised and translated from owners’ posts on an audiophile forum. They are the subjective views of their authors, not measurements or claims of Demograf Audio.

Which units the owners describe

Owners often call these converters “DAC7”, the TDA1547’s common nickname. The units quoted here were built to order by Dmitriy Gubchenko with an EL8 tube output stage and, in most cases, a tube-rectified power supply in a separate chassis. They differed in detail: one had only a coaxial input, one a USB input, one step-down output transformers by Sowter, one shared its chassis with a second DAC on the Cirrus Logic CS4397.

Today the TDA1547 version of the Reference Tube DAC is called Aphrodite. Unlike the multibit TDA1540 and TDA1541, the TDA1547 is a 1-bit bitstream chip. Aphrodite takes 16-bit / 44.1 kHz PCM over S/PDIF coaxial; the stock output stage is solid-state, and a tube stage is an option. In the designer’s voicing, Aphrodite is dark and velvety.

Sound, range by range

Bass

• One owner, whose loudspeakers had always been short of bass, heard the low range “cut through” at once: a foundation on which the whole of the music stands. He describes it as powerful and informative, without spilling into the midrange, and especially good on chamber and acoustic jazz.
• Another owner, after a later revision of his unit with output transformers, heard a dense, well-defined low end and more detail, with natural timbres.

Midrange

• One listener calls the midrange divine: he heard organ pipes he wanted to reach out and touch, something he had never heard from his loudspeakers before.
• Another speaks of a singing midrange and an unusually balanced sound; violins did not pour out in as wide a wave as from a CS4397 converter, but sounded remarkably beautiful and refined.

Treble

• One owner heard a characteristic lift in the upper midrange and lower treble, audible on both music and sweep tones. With battery power in his set-up, sibilance disappeared completely on his Beyerdynamic headphones, while that lift remained.
• Next to a TDA1541 converter, another owner heard the TDA1547 as cooler, with an occasional “icicle” in the sound. He changed rectifier tubes to tune it.

Detail and dynamics

• Owners describe high detail that does not read as a collection of small details. One compared it with his previous DAC on the ESS ES9018 and found the detail similar but far more musical: on the near-free-jazz duets of Chet Baker and Wolfgang Lackerschmid he could follow the musical thread the two players weave. Complex rhythms lose nothing for him, and Frank Zappa plays without any smearing; only on heavily produced industrial music do natural timbres matter less.
• Another heard the details become larger and more tangible, analytical yet not tiring, with very high dynamics in a soft, enveloping presentation.
• The same owner describes the ranges as clearly separated and yet smoothly joined.

CD against vinyl

Two listeners compared CDs played through the TDA1547 converter with vinyl.

• One owner compared CD and vinyl pressings of records he knows well. On Deep Purple’s “In Rock”, he had always heard on vinyl how the band’s playing and mood changed from track to track; through the new DAC he heard it on the CD as well. A Japanese K2 remaster of “Deep Purple” (the third album) drew level with the Japanese vinyl. His verdict: CD still did not beat vinyl, which remained warmer, mightier and more full of drive, but the gap had narrowed to a minimum and digital no longer tired him.
• On audiophile CD formats such as K2 and XRCD, the slight glassiness he used to hear disappeared.
• A visitor to the designer’s home compared a converter on the AKM AK4399, the TDA1547 converter and vinyl, with identical CDs and LPs. He heard tremendous resolution from the AK4399 and an analogue quality from the TDA1547 that brought it closer to vinyl. On a jazz reissue CD and LP sounded nearly identical; on classical music the period LP was a little freer. He concludes that good CDs played through the TDA1547 make a sensible companion to a vinyl collection.

Compared with other DACs

vs Berkeley Alpha DAC Series 1

One owner compared his DAC7 with a Berkeley Alpha DAC Series 1 and Berkeley’s USB converter, listening on Audeze LCD-3 headphones, and he reports a result against his own unit on several points. He found the Berkeley more detailed, refined and calm: delicate, without strain or heightened emotion, so that the smallest changes in dynamics and vocal timbre were easy to hear. After the DAC7, the Berkeley’s timbres seemed paler at first, but he heard that as the natural sound, and concluded that his DAC7 adds contrast. He heard the Berkeley clearly ahead in stage, volume and space. His DAC7 strongly emphasises solo instruments and the main musical line, which in his view masks the others; with the Berkeley he heard new layers in familiar music. His image of the two: the DAC7 is a powerful, fast mountain river sweeping everything before it, the Berkeley a calm, unhurried, self-assured aristocrat. He stresses that these were first impressions.

On loudspeakers the Berkeley had disappointed him, and he found it unsuited to dynamic or heavy music; until then the DAC7 had played better in his system than any DAC he had heard. A second listener, who mainly plays heavy music, also found the Berkeley weak on loudspeakers and on aggressive music, and had liked the DAC7 from his first listen: its strength, he writes, is musicality and involvement whatever the genre. After a later modification by another builder, the first owner heard space, precise positioning and full decays without losing its dynamics.

vs Mytek 192-DSD DAC

Another owner calls his DAC7 a very natural DAC, with high fidelity and a rich trail of decays and timbres. Next to it he heard a Mytek 192-DSD DAC as a little more dynamic and more accented, which can mislead a newcomer into hearing more detail. Over a longer listen he heard them as a metallic colouring, without a live atmosphere. “I am not saying the Mytek is bad; I am saying the DAC7 is very good.”

vs Weiss DAC202 and a prototype AKM converter

A visitor heard the TDA1541 and TDA1547 converters and a prototype converter on an AKM chip against a Weiss DAC202 and the Philips SAA7322/SAA7323 DAC built into the Sennheiser HEV90 (Orpheus) amplifier. The TDA1547 converter was his favourite of the day for its musicality, juiciness and engagement, with a well-balanced sound, a good stage and good dynamics. He heard potential in the AKM prototype and placed the HEV90’s Philips DAC between the TDA1541 and the TDA1547.

vs TDA1541, TDA1540 and CS4397

• One owner heard the TDA1541 as more comfortable and relaxing and easier on headphones, but in quick switching found the TDA1547 much more informative and interesting.
• Another heard a wow effect from the TDA1547, bright and brilliant, but missed the analogue quality of the TDA1541 and, still more, the TDA1540.
• Listeners who heard it next to a CS4397 converter found the CS4397 ahead in detail, scale and the lowest bass, and the TDA1547 ahead in the natural, singing midrange and in balance.

What owners report

• One owner came to the designer after a CD player had made his previous DAC redundant. After hearing the designer’s own system, he chose the TDA1547. His two-box unit has a single coaxial input, WBT connectors and a black wooden faceplate matched to his loudspeakers.
• Another owner asked for the smallest possible chassis with a USB input and an EL8 output stage. Later the unit came back for a rebuild: output transformers were added, the original USB board was replaced by an Amanero module connected over I2S, and the power supply was tidied up. Classical music from his computer, once his weak point, now sounded as it should.
• The same owner tried several rectifier tubes. With 6X5GT rectifiers from Sylvania the sound became denser and the midrange clearer, but some liveliness went; with Toshiba tubes it was right at once, and he stopped looking. RCA 6AC7 tubes in the output stage sounded pleasant but did not win him over.
• One owner listens to his DAC7 eighty per cent of the time and finds it hard to match musically with any multibit DAC; another preferred it to the solid-state DAC he owned.
• With the converter on, one owner hears dead silence in his headphones, even with its power supply a few centimetres from a plasma TV.

Reported problems

• A lift in the upper midrange and lower treble that one owner could hear on sweep tones.
• A cooler sound than the TDA1541, with an occasional “icicle”, for one owner, who tuned it with rectifier tubes.
• Strong emphasis on solo instruments and the main line, and a smaller stage than a Berkeley Alpha DAC Series 1, in one owner’s comparison.
• It needs a system of matching quality: one owner calls this its “big minus”.

Summary

Owners describe the TDA1547 converter as fast, dynamic and detailed, with a full, informative low end, a singing midrange and detail that serves the music. Two listeners heard it bring CDs close to vinyl, and in sessions with a Weiss DAC202, a Mytek and other chips it was the favourite of several listeners.

It is not neutral. One owner heard it add contrast and emphasise the main line next to a Berkeley Alpha DAC, others found it cooler than the TDA1541, and it asks for a system of its own quality.

Which Demograf Audio piece fits

• Aphrodite is the TDA1547 version of the Reference Tube DAC: 16-bit / 44.1 kHz PCM over S/PDIF coaxial, no DSD, a solid-state output stage as standard and an optional tube stage on 6Zh4, EF14, EL8, AL4 or ML6 with a 5Ts4M rectifier.
• If you also want USB, high-resolution files or DSD, Hyperion on the CS4397 takes up to 24-bit / 192 kHz and DSD256 over USB. See our Hyperion owners’ review.
• Hades and Bellerophon amplifiers can carry a built-in DAC on the TDA1547 chosen at order time, and Charon is our external master clock.

Every converter is made to order by Dmitriy Gubchenko, with a one-year warranty (extra warranty available: +1 or +2 years).