Reviewer: Srajan Ebaen
Financial interests: click here
Sources: Retina 5K 27" iMac (4GHz quad-core with Turbo boost, 32GB RAM, 3TB FusionDrive, OSX Yosemite. iTunes 12.2), PureMusic 2.04, Qobuz Hifi, Tidal Hifi, Fore Audio DAISy1, COS Engineering D1, Metrum Hex, AURALiC Vega, Aqua Hifi La Scala MkII, Apple iPod Classic 160GB (AIFF), Astell& Kern AK100 modified by Red Wine Audio, Cambridge Audio iD100, Pro-Ject Dock Box S Digital, Pure i20, S.A. Lab Lilt [on loan]]
Preamplifier: COS Engineering D1, Nagra Jazz, Esoteric C-03, Vinnie Rossi LIO (AVC version)
Power & integrated amplifiers: Pass Labs XA30.8, FirstWatt S1, F6; Crayon Audio CFA-1.2; Goldmund Job 225; Gato Audio DIA-250; Aura Note Premier; Wyred4Sound mINT; AURALiC Merak [on loan]
Loudspeakers: Albedo Audio Aptica; EnigmAcoustics Mythology 1; Sounddeco 2; soundkaos Wave 40; Boenicke Audio W5se; Zu Audio Submission; German Physiks HRS-120, Gallo Strada II w. TR-3D subwoofer
Headphones: ALO or Forza Audio Works rewired Sennheiser HD800, ALO-rewired Beyerdynamic T1 & T5p, Forza Audio Works rewired Audeze LCD-2 and LCD-XC, ALO-rewired AKG K-702; stock-cabled HifiMan HE1000, HE-6, HE-560 both with upgraded pads, Forza Audio Works rewired MrSpeakers Alpha Dog and Alpha Prime; EnigmAcoustics Dharma D1000; Aëdle VK1; Ortofon eQ5
Headphone amps: Bakoon AMP-12R, Eximus DP1, Stello HP100MkII, Questyle CMA800R (x2), Eversound Essence, Aura Vita
Cables: Complete loom of Zu Event MkI and MkII; KingRex uArt double-header USB; Tombo Trøn S/PDIF; van den Hul AES/EBU; AudioQuest Diamond glass-fibre Toslink; Arkana Research XLR/RCA and speaker cables [on loan]
Power delivery: Vibex Granada/Alhambra on all components, 5m cords to amp/s and subwoofer
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves and Krion or glass-based Exoteryc stand/s for amp/s
Sundry accessories: Acoustic System resonators
Room: Irregularly shaped 9.5 x 10m open floor plan with additional 2
nd-floor loft; wood-paneled sloping ceiling; parquet flooring; lots of non-parallel surfaces (pictorial tour here)
Review component retail: €1'500

Under Nippon Hifi, Jani Leppälammi acts as Soulnote's Finnish importer and doubles as brand ambassador/sole distributor to Europe. It was in his latter role that he contacted our obscure Geneva hifi embassy for some unilateral talks on Soulnote's global visibility. Actually, he simply wrote in requesting a review on their new SD300 headphone amplifier. As he explained, until now this brand under the leadership of Mr. Norinaga Nakazawa, president of the CSR Group, hadn't really pursued European reviewers from their end. With my Swiss residence outside the EU, he'd now get Koki-san in Japan to handle my review loaner directly so he wouldn't need to hassle with customs. To learn more about the brand, I foraged through Jani's English pages. Here one learns that Nakazawa's career began at the Standard Radio Corp. where he was an R&D engineer on early tape recorders and players. In 1971, Superscope, then part owner of Marantz, acquired a 50% stake in Standard Radio Corp. Now they were tasked with R&D on mid-level components and receivers. By 1975, the company had changed its name to Marantz Japan Inc. By 1980 Superscope sold off some overseas assets plus the IP rights and sales division of Marantz to Phillips Corp. in Holland. Nakazawa was instrumental in the development of their Marantz CD63; involved with the Phillips LHH100, a 2-chassis CD player; the LHH500, the first 1-bit player; the AV1000 two-chassis AV controller/amp and much more.

Yet what had been an attractive partnership for our engineer because Phillips took Marantz upmarket eventually diluted. Marantz left Phillips to become part of D&M Holdings Inc. instead which had also absorbed Denon. Here the bottom line became more important than technical innovation. Nakazawa exercised a management buy-out to create his new company, CSR Inc. 50 engineers accompanied him. The Soulnote brand is the outcome of his departure from Marantz and his attempt to resurrect that company's original focus. Whilst newer in name, Soulnote has a 40-year+ legacy of extensive experience behind it. The name itself is suggestive of a committed return to Norinaga Nakazawa's core values. Marantz reborn without the bean counters?

With this history as retold by Jani, here was an engineering-driven company with a very serious past in mass-market and transitional high-end gear. They promised to be focussed on value whilst leveraging the necessary know-how on larger-scale manufacturing and associated infrastructure to work this sector successfully. So why hadn't we heard sooner about them since their June 30th, 2004 launch now dated back more than a decade? By July 1st 2010, they were 53 employees entrenched. I had visions of early but massively scaled-up Bakoon centred exclusively on their domestic Japanese market before breaking out. And I sensed a welcome if rarer opportunity to do our bit in moving the overpriced hifi narrative into a more accessible everyman chapter à la Denon, Onkyo and Yamaha.

Thus it was that I came to sign up for the SD300 headfi machine despite having absolutely no details on it yet. After my initial exchange with Jani then Koki-san, a lot of time passed because "there was a pretty bad mistake with their Japanese website host and they had to decide on appropriate action. They are not really that knowledgeable about the Internet yet but pursuing online reviews obviously requires a global English website. This had to be built before we dispatched review product." Perfectly sensible indeed. Timing is important. Here it meant waiting for Soulnote's global website.
As it turned out, the SD300 would be featured not unlike the super-expensive Goldmund Telos headphone amp. It included a 32/384PCM/DSD128 USB converter with XMOS transceiver and 24/192 coax and Toslink; plus one analog input. Then the Japanese one-upped the Swiss with defeatable 4.2/8.4Vrms RCA/3.5mm/XLR outputs to double as preamp with red-on-black alphanumeric display. Headfi connectivity was via 6.3mm and 4-pin XLR, with attendant specs of 190mW/32Ω power, 5Hz-80kHz bandwidth -3dB, 0.0015% THD/1kHz, a brilliant SN/R of 115dB and channel separation of 105dB.