The 404 Reference integrated amplifier

Following the runaway success of The Moonriver Model 404 (Standard), Moonriver Audio decided to move a step further by improving on the already excellent design platform of the Standard 404 model. The Moonriver Model 404 Reference achieves even better performance over the Standard Model, while retaining a sensible price point.

Just like the Standard Model 404, the 404 Reference amplifier will extract hidden elements, and render textures from within any audio format; but with the capability to drive any speaker on the market – despite its moderate power. Only the source, speakers and room will set the performance limit. Its culture will suit all music, as the Model 404 is by design, set to define the faintest nuances of which tonal integrity is composed.

The power supply section has been improved to the maximum. The 404 standard uses a total of 57000uf capacitance. The 404 Reference lifts the capacitance to a spectacular 107000uf of which 21000 of them are reserved for the preamp only.  This enormous increment expands the driving behaviour; the dynamic character; digs out more detail; low level information; a deeper and more articulate soundtstage; space between instruments is vast, while the bass has greater authority and is more confident than ever before.

The texture of each individual instrument is exposed exponentially in comparison with the Standard version. A fully discrete preamp section serves to provide acute dynamic awareness, while a high output stage that is custom-optimised for bandwidth and distortion, gives neutral character and transient fidelity. A sophisticated selection of components fuses the design against tonal traits, therefore preserving naturalness throughout the shortest feasible signal path.

Optional Phono Stage

Model 404 Reference comes with two options in the phono stage department; one is MM only and the other is MM/MC selectable. Both follow the exact quality principles that Model 404 Reference is built on. Quality components and massive power supplies are also employed here, to efficiently accommodate very low noise, high performance op-amps.

The gain in the MM/MC phono can be adjusted, simply by changing the dip switches position. The MC input load can be set also, by replacing the original 100 Ohm input resistor with a higher or lower value. No soldering is required.Specifications

• Inputs: 5 (line 1 and 4 optionally occupied by phono stage and USB DAC respectively, 1 x tape loop)
• Outputs: 2 x preamp out, 1 x rec out
• Max output power: 50 W / channel into 8 Ω
• Frequency response: 10 Hz to 50 kHz
• Total harmonic distortion: 0.05%
• Signal to noise ratio: 85 dB (line)
• Idle Consumption: 22 Watts
• Dimensions (mm): 430 (W) x 390 (D) x 135 (H)
• Weight: 13 kg