SALON AV: S.A.Lab Hercules MkII

Nikolay EFREMOV
Автор
Article on the reviewer's resource
February 03, 2017
Date

Of all the Russian audio manufacturers only Alexey Syomin is probably audacious enough to start a new project of such a scale for investments are huge — as well as the risk of failure. Of course if one doesn't try to create High End audio from junk bought at a garage sale — counting on innermost esoteric knowledge and magic cables.

RESURRECTED IN MARBLE

Each project of Alexey receives maximum funding but without fanaticism or pomposity. He works for audio connoisseurs who appreciate a truly high quality audio device… and have enough money to buy it. Compared to 1990s the number of such people in Russia grew considerably but not sufficiently to support Russian manufacturers with steady inflow of cash. A considerable share of S.A.Lab's products is sold in Europe — the fact that can be regarded as a reliable proof of quality. But more important is the sense of solidity, thoroughness and a tendency to use original engineering solutions even for budget models.
In this respect the new Syomin's project far exceeds his previous achievements. Hercules Mk II combo consisting of a preamp and a pair of mono blocks weighs more than 400 kilos and is delivered in three huge crates. Last year Hercules's pre-production sample received the Product of the Year prize at the Moscow Hi-Fi & High End Show being nominated in the Component Manufactured in Russia category but never reached the mass-production stage. As soon as the Show ended, a number of ideas for improving this 'monster' was put forward commencing the work on MK II version. By the way this fact is in itself a proof of Alexey's attitude: without 'creaming off' his previous model he started designing a new one with the aim of not just face-lifting it but looking for a radical overhaul of schematic and architecture.

«The most important (and costly) feature is that filaments in all the tubes incl. powerful ones are heated by rectified and stabilized voltage».

Hercules Mk II has three-level architecture. The lowest one is comprised of the power source featuring 1200 VA transformer, Schottky diode rectifier and a bank of custom-made capacitors (100,000 µF/600 V). To eliminate power surge while they are charging a gradual start of anode feeding is provided (the corresponding voltage amounts to 580 V). The most important (and costly) feature is that filaments in all the tubes incl. powerful ones are heated by rectified and stabilized voltage. This approach leaves no chance for hum, a real scourge of a tube amplifier.

The second level contains additional feeding decoupling circuits with smoothing capacitors and output transformers. Power-to-size ratio of the latter ones is also 1200 VA; the technology of hand winding and the way windings are switched is designed by S.A. and will probably be patented in the near future. The transformers' tape cores are manufactured from the best Russian electric grade sheet.

And finally the upper level which contains the cooling system: one can feel a powerful current of heated air escaping form a ventilation grille. Output stages feature eight (four in each shoulder) thoroughly matched 6P36С tetrodes working in a push-pull ultralinear mode. Let me remind you that such a mode with a tap for screen grilles combines the advantages of triode stages (low output impedance, short harmonics plume) whilst the decrease in output power is insignificant. Eight substantial valves produce 200 W working in class A no matter what the speaker impedance is: Hercules is equipped with binding posts for connecting both 4Ω and 8Ω speakers. The signal voltage is amplified by 6072 double triode and accelerated by a driver utilizing 12W 6v6 pentodes.

The levels are connected by means of RPN military grade posts with silver-plated knife contacts. In case of malfunction any level (shelf) can be easily extracted and tried on a test bench.

«Output stages feature eight (four in each shoulder) thoroughly matched 6P36С tetrodes working in a push-pull ultralinear mode».

Pre amp is designed for working with one of five line sources remotely switched. It's equipped with push-pull transformer output based on a pair of 6P9 pentodes working as triodes. Essentially it's a small-scale power amp with output impedance of about 22 Ω capable of working with cable of any length. In my opinion the only thing it lacks is a headphone output. The schematic is completely suitable for it — only the socket is missing.

Input stages are based on rare and expensive Siemens C3g tubes featuring low noise level and enormous resource. Volume is controlled by step attenuator utilizing relays with micro-current contacts.

As seen on the picture the new Hercules threesome's look is truly monumental. He decided to finish cabinets with American walnut tree massif (this material is used to manufacture rifle butts) and genuine Carrara marble (the huge slabs of it are delivered to Russia from Italy). According to Alexey finding pieces of similar color and texture is not as easy job and a lot of marble is to be discarded.
We listened to this combo for two days in a row; first with Mark Levinson №512 CD/SACD-player then with Studer A-807 Mk II tape recorder playing back master tapes. The speakers were of similar quality level — 145-kilo closed cabinet Magico M3s with graphene cones and diamond coated 28-mm twitters.

«Designer decided to finish cabinets with American walnut tree massif and genuine Carrara marble».

We started with listening to CDs. The output was about 60% of the maximum level. At first the sound seemed too loud but gradually our hearing adapted to it. Dynamic range was incredibly wide but more important was the spine-chilling agility and easiness of transitions from pianos to thundering fortes. It immediately occurred to us how unusual this speed was and how unaccustomed to it we grew to be. Intervals between tracks were dead silent but intermissions between parts of a single musical piece were alive with the breath of audience. I instantly recalled that in order to avoid an emotional collapse while editing a radio show the intermissions were filled not with demagnetized tape but with a 'sound' of an empty recording studio. Powerful transistor amps tend to 'bleach' low level sounds and sometimes ignore them completely giving music a mechanical tinge. The Hercules combo held our attention to the last note of each track helping us to discern the seemingly insignificant nuances. But it is them that created the overall impression of a musical piece.
Talking about micro dynamics I don't think I can remember another audio system capable of demonstrating the difference between CD and so vividly. The SACD provides an entirely different level of spaciousness, harmonic accuracy and the feeling of 'wholeness' together with incredible immediacy of the audio picture. By the way, you can listen to the Hercules combo at low volume for neither musical balance nor aerial perspective suffers from it. Even high and low frequencies roll-off — an unavoidable trait to our hearing — is less obtrusive than usual.

Bass was marvelous (nimble and agile) — as well as the middle which was reproduced without unintelligible hum and a vague 'rubbery' constituent appeared only at the very bottom. This seemed to be the result of a lower dumping factor (compared to the one of a transistor amp). In this respect the most suitable speakers for these power amps would be the Altecs, early JBLs etc. In other words speakers with huge woofers equipped with light paper cones. But even with the low-impedance Magico the amps produced impressive results.

Especially so when we connected Studer and played back a master tape recorded as 15 ips. Frankly I never heard such a hurricane of dynamics. We were literally swept out of the room (despite the fact that the volume level remained the same) and had to continue listening from a neighboring room through an opened door. The sound was succulent and meaty with luxurious middle and bright 'analogue' frequencies. Michael Jackson's Thriller exhibited so many sounds and unexpected effects we never noticed before that our heads started spinning. The audio space was grossly overpopulated, but we noticed no hint of either inaudible mess or loss of timbre clarity. It seemed impossible to bring these monsters to the brink of clipping. We changed the genre to jazz quintet and voila — spaciousness, airiness and depth of audio scene were gloriously evident. Even tape noise during gaps was perceived as an essential element of the general picture.

«Dynamic range was incredibly wide but more important was the spine-chilling agility and easiness of transition from pianos to thundering fortes».


We had to admit that the room was too small for the Herculeses; they needed more space — preferably a high ceilinged hall with about 5 m distance between listeners and speakers (the way it is in a small jazz club). In tis case you will be listening not to a pair of speakers but to the absolutely real soundstage sitting on the best seat.

«You can listen to the Hercules combo at low volume for neither musical balance nor aerial perspective suffers from it. Even high and low frequencies roll-off — an unavoidable trait to our hearing — is less obtrusive than usual».

«The audio space was grossly overpopulated, but we noticed no hint of either inaudible mess or loss of timbre clarity».


DESCRIPTION
Model
S.A.Lab Hercules MkII
Manufacturer
S.A.Lab (Russia)
Output: 250W (4Ω) || Signal/noise ratio: –99dB|| THD: 0.03% (150W, 4Ω) || Size (mono block/pre amp): 555 х 685 х 700mm/465 х 270 х 480mm|| Weight (mono block/pre amp): 175/57kilos || Price: 6,000,000 rubles.

Editorial office thanks SoundProLab salon for its help in conduction the listening tests.

MUSIC

CD/SACD
• Celine Dion, «All The Way… A Decade Of Song». SACD Sony 2004
• «Tutti! Orchestral Sampler». 24 bit HDCD Reference Recordings, 1997
• Jean Sibelius, «Concerto for Violin and Orchestra in D minor, op.47». Anne-Sophie Mutter and Staatskapelle Dresden. Deutsche Grammophon • GmbH, Dresden 1995.
• Noisia, «Split the Atom». 2 CD, Mau5trap, 2013

MASTER TAPES
• Ray Brown, "Live in Nagykanizsa",1998
• Freddie Mircury & Montserrat Caballe «Barcelona», 1987
• Michael Jackson «Thriller», 1982
• Rachmaninoff «Piano Concerto N3». Ashkenazy/Previn