Hardware Reviews

Moonriver 404 Reference has the power

MoonRiver model 404 reference review

Moonriver Audio Model 404 Reference amplifier

Before I discovered the Model 404 Reference I spent some time with the Moonriver Model 404 amplifier and I heaped a great deal of well-merited praise upon it. Our Editor added the cherry on the cake by awarding it the coveted Editor’s Choice award. The final sentence of my review was:“I shall be genuinely sorry to see the Model 404 depart. If I was in the market for a new amplifier this would be at the top of my list. I can’t wait to get my hands on the Reference model – the mind boggles as to how good that is going to be!”. Little did I realise that it would be another two and half years before that wish would become a reality – but my goodness my patience was  richly rewarded.

The overall appearance of the Reference is identical to its sibling save for white script being replaced by gold script, in keeping with the premium status of this model. Subjectively, it works. The Reference has real rack presence. The front panel layout is identical. Looking from left to right, we find a control for source selector, then a small toggle switch for adjusting the lights on the front panel. Below that is the on/off power button and then a rotary control marked Tape Monitor. There is a resurgence of interest in both open reel and cassette recorders and players, but this feature also allows the user to use “a digital or analogue room correction processor, a buffer, a noise reduction system or indeed any other line device available to improve the sound of a connected source”, in the company’s own words.

MoonRiver model 404 reference review

Right in the centre is an amber LED which confirms that the unit is switched on and operational. To its right is a rotary for balance control (hooray), and a mono/stereo replay switch (hooray again). And finally there is the volume control, which has just the right amount of sensitivity to allow for precise volume control.

The rear panel is similar to its sibling’s, but offers WBT Nextgen speaker terminals, which the company says ensure “the massive flow of current from the amplifier’s output stage is able to drive even ‘difficult’ loudspeakers.” There are four line level inputs with number 1 and number 4 being marked for use with the optional MC/MM phono stage and the optional DAC respectively. There are then two pairs on inputs for tape in and tape out. Next to them are two pairs of pre-amp line level outputs, the WBT loudspeaker terminal and lastly, on the far right is the IEC power input. This keeps components optimally warm for instant listening pleasure. A soft start circuit based around a 30A relay has been designed to give the amp longevity measured in decades.

Neither the phono stage nor DAC were installed on the review sample that was here, so I shall not be commenting on those. However given the attention to detail throughout this amplifier I am confident that they will be very worthy additions. They can be added to the amplifier at the time of purchase or any time thereafter, which means that on the digital side especially you will not be buying obsolescence as standard if you choose to have the DAC module fitted. I would suggest that you always ask your supplying dealer to fit these modules.

MoonRiver model 404 reference review

404 Reference under the hood

The main changes from the Standard to Reference model are, as my American friends would say, under the hood. Here, there have been major changes made in the power supply section. The Standard model has 57,000 µF capacitance which is lifted to a whopping 107,000 µF in the Reference, and of that 21,000 µF are reserved for the  fully discrete preamplifier section. The objectives of this increase were to expand on all the good things about the output of the standard model, improving dynamics, digging out more detail and low level information while giving the lower frequencies more heft and authority. Given that I had enjoyed the Standard model so much, I was curious to learn whether all these goals were met when real life intersected with theoretical gains. Output still quoted as 50 watts per channel.

When the 404 Reference was installed in my system it was connected to my wonderful Harbeth Compact 7ES XDs with Audioquest Robin Hood cable. Sources were my modified Linn Sondek LP12, with a Gold Note PH10/PSU on phono amplification duty, and my trusty Yamaha CD-S3000 SACD/CD player, with its DAC also being the conduit for my television sound. An Auralic Aries Mini streamer completed the options for sources. About a week after the installation, my Harbeths gave way to a pair of Node Audio Hylixa Signature loudspeakers. (Review to be published shortly).

Listening to the Model 404 Reference

After allowing the amplifier a few hours to get up to room temperature I cued up the record which seems to spend more time on the platter than most others at the moment. It is Dave Alvin’s 2011 recording Eleven Eleven, in its 10th anniversary reissue on the YepRoc label. The opening track is Harlan County Line and it sprang into the room with incredible realism, with Alvin’s world-weary baritone projecting wonderfully into the room, his battered Stratocaster full of character and the supporting musicians arrayed wonderfully in a three dimensional soundstage. I was gripped from the start and played all four side of the album without interruption.

MoonRiver model 404 reference review

What I loved about the Model 404 came flooding back but this time with added verve and vivacity. I heard little details in the recordings that had not been noticeable before, and the rhythmic drive that I had enjoyed before was even more pronounced. Do not interpret this as criticism, because it is quite the opposite, but having heard the 404 Reference model I am astonished about how much extra musicality and performance the power supply changes have added to the already excellent Model 404.

The arrival of the Node Audio Hylixa Signatures paused listening for half a day, as my Harbeths and their stands were removed from the room and the ultra-modern looking newcomers were painstakingly installed by the two gentlemen who had brought them. They asked about the amplifier (as you would expect) and were polite but clearly slightly sceptical about a mere 50watt amplifier being adequate for their product. (In fairness, Node Audio quote a suggested amplifier output of 50-150 watts, but as they said to me, more is better than less.) I had left the room to allow the installation to be done without me wittering away in the background. Eventually they were sufficiently satisfied and invited me back in to hear the loudspeakers.

Moonriver Audio Model 404 Reference review

Using the Auralic for convenience, we sat down and listened to several tracks which they recommended to me on the Qobuz streaming service, almost all of which was new to me, being mostly dance and electronic music. However, they chose well, because the music that came forth from the Hylixas was little short of astonishing. The loudspeakers were cold but even in that state their potential was very obvious. My two guests, who had not come across Moonriver before, expressed their delight at the pairing and actually apologised for having doubted that a 50 watt integrated amplifier (which, by the way is less than one fifth of the price of the loudspeakers!) would be up to the job. They then left but one of them had booked a night in a local hostelry with the intention of returning the following morning to make any adjustments required after an afternoon and evening of use.

On his return, once he was satisfied that the Hylixas were giving of their best in our room, I played him the first side of the Dave Alvin album, and I think both of us were delighted with what we heard. The Auralic Aries Mini is a good streamer for its price, but it took the much more expensive vinyl front end to really allow th 404 Reference/Hylixa pairing to shine. Mr Alvin and his band filled the entire room with a soundstage of greater depth height and width than even my beloved Harbeths could ever manage.

MoonRiver model 404 reference review

Left to my own devices, I then had several days where I accomplished very little of the business end of this reviewing malarkey, i.e. writing, because I could not stop listening to music. Even the notes which I jot down when I listen had long gaps between them. I worked through all sorts of music, from a compilation of country music stars singing Rolling Stones songs to celebrate that band’s 60th Anniversary, called Stoned Cold Country to Grant Green’s The Latin Bit on the Blue Note Tone Poet reissue, by way of blues, rock, choral, classical and pretty much every other genre. This system, with the 404 Reference at its beating heart, was as immersive as any I have heard, here or elsewhere. Regular readers will know that one of my favourite pieces is Pink Floyd’s Echoes, which takes up the whole of the second side of Meddle. Its epic sweep has never been better portrayed in my home than it was by this system, with the contribution of each band member clearly heard and placed in the soundstage, without any detriment to the musical flow. Hard to believe that it was released over half a century ago, it sounded so vivid here.

MoonRiver model 404 reference review

Model 404 Reference conclusion

Sometimes Special Editions are more the product of the marketing department than the engineering one, but not here. The improvements to the powertrain in the 404 Reference have promoted it to the super-league of sub £5k amplifiers. The Standard unit is still an exceptional value at its price point, but the Reference takes that already winning formula and turns it into something very special indeed. If there was any justice, the name Moonriver Audio ought to be mentioned in the same breath as that of many much more widely acclaimed brands. I congratulate the Moonriver team on this achievement – they are going to have their work cut out to produce something better than this. I know it is only May, but I think I have already identified a shoo-in for one of my Product of the Year nominations.


Type: integrated stereo amplifier
Analogue inputs: 5x RCA
Phono input: optional MM or MM/MC
Digital inputs: optional USB
Analogue outputs: tape out RCA, 2x pre-out RCA
Bluetooth: N/A
Headphone output: N/A
Speaker outputs: 5-way binding posts
Power Output: 50W into 8 ohms
Features: mono mode, balance control, tape monitor
Dimensions (HxWxD): 135 x 430 x 390mm
Weight: 13kg
Warranty: 3 years

Price when tested:
Moonriver Model 404 Reference £4,495
MM/MC phono stage £500
Manufacturer Details:

Moonriver Audio
T +46 (0) 765905066


integrated amplifier


Chris Kelly

Distributor Details:

Whole Note Distribution
T +44 203 911 5549

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