Soulnote Audio Amplifiers

Soulnote is a high-end audio brand from CSR Inc., headquartered in Kanagawa, Japan. CSR was founded in 2004 by the former members of Marantz Japan bringing much in-house expertise.

Hideki Kato, Soulnote’s ‘Chief Sound Manager’ since 2016, has been working in high-end audio since late 1980s, having been deeply involved in the development of the legendary products from NEC and Philips.

During his long career, Kato has designed both digital and analogue equipment. One question kept bugging him, which was why something which measured better on the scope did not necessarily translate into improved audio quality. Indeed, he found the opposite to be true in some cases. During our evaluation of products over many years, when deciding on products for our curated portfolio, we have often found this to be the case. Technical specifications and scientific measurements tell you nothing about sound.

 Kato believes in listening to develop, not in just electronic design on paper. This focus on listening moves from the circuit and parts to the chassis development too, where Soulnote have some innovative technologies including floating housings. All driven by the sonic advantages they bring not just the aesthetics.

Kato is pushing for what he calls, ‘Dynamic Performance’. Through his listening tests, he has developed products with NOS (non-oversampling) mode for PCM Playback in their DACs, as well as Zero Negative Feedback designs in their amplifiers. Both of these technologies lower measured performance, but to the ear they produce much better dynamic performance and listening enjoyment. Soulnote believe that the timing of the impulse is all important, as is the recovery of the impulse. The use of their technologies enables the fastest signal possible, and thus the best timing.

All of the Soulnote’s series of products share a very similar chassis design and size within each range for a very cohesive system look. All components are available in silver or back anodised aluminium.

Soulnote Series 1 components have a thick, milled front panels but conventional basic chassis to the top, bottom and rear.

Soulnote Series 2 units are built from milled aluminium panels on all sides, as well an introduction to their floating chassis technology.

Soulnote Series 3 units are built with absolutely no compromise. As well as milled panels, it incorporates all of their floating-chassis technology: top and bottom panels, along with the input and output sockets

In our listening tests, we found the A1, A2 and A3 integrated amplifiers to have a large class A component as these run quite warm. They deliver a rich and satisfying sound brimming with low level detail. Bass is authoritative and nuanced. Midrange, where most of the connection to the music is made, is rendered with real emotion.

The A1 offers exceptional value for money as it has a more basic chassis, whilst internal circuit designs still includes an in-house developed relay volume control to minimise channel imbalances and maximise sound quality.

The A2 offers a more expansive sound stage, with a more detailed rendition of any quality recording. A superb amplifier offering exceptional sound quality for the price point.

The A3 is a statement level build quality and offers a yet more open sound picture, more delicacy in the performance, and a more holographic soundstage.

Both the A2 and A3 integrated amplifiers have been designed to also work as stand-alone amplifiers with two working in tandem. The A-2 does this through a BTL (Bridge Tied Load) mode which makes each amplifier a mono, raising power output significantly. The A3 does not have a mono mode (it is already a dual mono amp design) but two units can be used to bi-amp your speakers, doubling the power of the standard unit. In both instances one amp will act as the master, to control both units. This allows for a strong upgrade path and is a real differentiator in the market.