Design & Ergonomics

Moonriver had a very clear vision when conceiving the Moonriver 404 Reference amplifier: Classic design with a modern touch; high-quality materials such as over-sized aluminum controls, solid walnut cheeks, sturdy chassis and an ergonomic user interface.

There are no ‘for show’ aesthetics here, no display with complicated serial menus and hidden functions, nor a single multi-function knob for ‘minimalistic’ purposes.

The heart of the Moonriver 404 is pure and minimal, but the interface is user-oriented and easy to operate by anyone in seconds, with no need to resort to the user manual. Four knobs and three switches give direct access to any function.

Modular Architecture

Moonriver 404 Reference amplifier is modular like its brother; it can accommodate an MM or MM/MC phono stage and a USB asynchronous DAC.  Fitting these modules is simple, and can take place at any time, on or after purchase.  The USB DAC may also be upgraded with a newer version to meet future needs and technologies.

Balance Control

You may find this feature to be vanishingly scarce in audiophile products as a result of today’s ‘minimalist’ design mentality and the various myths accompanying it. However, balance control addresses a common problem: speakers that are positioned in asymmetry, in a non-balanced room environment. It therefore provides the simplest tweak towards achieving a proper soundstage.

Living rooms and house furniture are meant to serve everyday life and may not be positioned in an ideal listening spot, evenly distanced from each speaker to form an equilateral triangle. It is also not uncommon for one speaker to have to be placed nearer room boundaries than the other, having various frequencies boosted in a more or less predictable pattern. More often than not, balance control is incredibly useful as it drastically helps overcome volume level unevenness and in some cases, even reclaiming the stereo effect and the resulting focused sound stage.

It is to be expected, the way the balance control is implemented on the Moonriver 404 Reference amplifier – in parallel, will not degrade or affect the signal in any way that is determinable.

Discovering the layout

Model 404 Reference, like the standard model, incorporates no less than 5 separate power supplies, each featuring overload protection. The power amplifier specifically runs on a dual mono configuration, beginning from separate windings on the toroidal transformer.

WBT nextgenTM speaker terminals ensure the massive flow of current from the amplifier’s output stage, is able to drive even “difficult to drive” speakers.

Signal switches are implemented via relays, while volume attenuation is trusted on the legendary blue ALPS pot.

A soft start circuit based on a 30A relay ensures that even the on/off switch is thought out to work with virtually no burden or wear for decades.

The 404 Reference chassis reduces unwanted resonant vibrations even further with absorbent materials, and better integral mechanical support.

Components are carefully selected for both suitability and reliability. We make no use of surface-mount in analog circuits, despite the fact that through-hole production costs more, and requires advanced space management & layout strategies.

Each element utilised has to be of proven stability and sustained higher performance – proficient implementation provided, before making it into our analog paths.

As for the sound, we are not to say whether Model 404 Reference is virtually transparent or inherently forgiving. Voicing it to appreciate the playlist and respect the user at all times has been the sum of all of our effort; a sincere effort to achieve effortlessness.

The Importance of Tape Monitor Loop

Most of today’s manufacturers probably reject the idea of their product featuring a tape loop. At Moonriver Audio, it has been concluded that the tape monitor loop is essential. Not only does it add the option of monitoring the difference between recorded and source material in real-time, it also, and most importantly, makes possible to insert to the chain – at will – a digital or analogue room correction processor, a buffer, a noise reduction system or any other line device available to improve the sound of a connected source.

Stereo/Mono Switch

The pristine era of analogue recording being long gone, features like the stereo/mono switch have been gradually chased out into obsolescence. Who wants to go back to one when they have two channels? “Less is more” and “more is better”. Well…

With the resurgence and interest in vinyl, whether the current rage; fashion or a real movement, countless monaural pressings emerge out there, often along with their digital… image.

Too many of them, among others waiting to be rediscovered, have currently become collector’s items, 78 rpm direct-cut gems being no exception. This is not unreasonable, as what happened between say the 30s and the 80s in terms of both musical interpretation and recording technique is by many considered to be “most of the music” – this sentence doing perhaps no justice to stunning actual developments in creation and reproduction.

The stereo/mono switch gives you the chance to enjoy recording art milestones with respect to how they were initially intended to please; in genuine mono, 2-channel, doing away with artificial phase discrepancies induced by a mandatory stereo mode.

So, ‘less’ may well be ‘more’, but ‘better’ is to have a choice.