Hardware Reviews

Musical Fidelity M3si


Can this Musical Fidelity integrated with onboard DAC sound as good as it looks? Réne closes his eyes and lets the music work its magic.

When I was asked to pick a Musical Fidelity amplifier for a review I was attracted to the beautiful silver front and the quietly shining LEDs of the M3si, but I learned many years ago that looks are not all that matters, so I closed my eyes and started listening. The M3si is a dual mono amplifier, the only shared element is the toroidal mains transformer, the power supplies and amplifiers for the left and right channel are completely separate. The amplifier runs in the classic AB mode, which means a low bias current is fed to the power transistors, whereby the first Watts are delivered in class A, and high power in class B. This kind of design is energy efficient yet able to deliver substantial power when required. Musical Fidelity likes to make use of SMT (surface mount technology), using mini components on the circuit boards, because the technique the mechanised board population process is extremely reliable. Because SMT saves space, Musical Fidelity is able to offer more inputs and increase the continuous power output of the amplifier. The M3si has five analogue inputs, including MM phono and a switchable input for line or home cinema bypass use. In addition there is a USB input for data rates up of 24bits/96 kHz, followed by a digital to analogue analogue converter. Obviously there are speaker outputs, plus a line out and a pre-out, this last one suitable for connecting an additional power amplifier or a active subwoofer.


M3Si Back Panel


The output power of the M3si is specified as 85 Watts per channel into 8 Ohms, with an available peak current of 25 Amps. The damping factor is relatively modest with a value of 36, which implies that the feedback is low. The input impedance is 40kOhm for the analogue inputs and 50kOhm for the phono input with a nominal sensitivity of 3mV, good enough for high output moving coil cartridges. The USB input will work with generic Windows or iOS drivers. My music server running Linux recognized the USB receiver without a problem. It might seem a restriction that USB does not accept sample rates over 96 kHz, but on the other hand you don’t need to install a driver to use it.

To try all options on the M3si I used a Bluesound Node combined with a NAD M51 D/A converter. For the USB input I used a Vortexbox media server. Cabling is sourced from AudioQuest, Supra, Crystal Cable and Simply Audio. The loudspeakers are Harbeth P3ESR mini monitors on vintage Sonus faber stands. After various comparisons with all kinds of music I chose the most expensive solution to assess the M3si, the Bluesound Node plus M51 DAC. With 44.1 kHz ripped CDs it is clear that the converter in the M3si falls short of the NAD. Which you would expect, the M51’s only task is to convert and it carries a heavier price tag than the complete M3si. Moreover, the differences were clearly audible in the stereo image, the detail, impact and sound character. The amplifier part of the M3si deserves a compliment because it shows these differences very clearly.

It is essential that the amplifier is fully warmed up, it will sound its best if it’s switched on half an hour before listening starts. With Stacey Kent singing on The Boy Next Door (Candid) the ease with which the amplifier performs is especially striking. The sound is deliciously free from the loudspeakers and the amplifier seizes every chance to reproduce the dynamics and life in the music. It’s a complete soundstage where the volume certainly does not need to be high to produce a believable experience. But play loud if you want to, because even with low efficiency Harbeth P3ESR speakers it does not run out of steam. The lower notes are defined and tight, the deepest tones being limited by the loudspeakers. Stacey is placed forward within the stereo image, the band further back. With the media server this virtual image is significantly less wide and more limited in height and depth, a reflection of the USB input rather than the amp. Turning back to Stacey means enjoying the acoustic instruments in the band. The same goes for Paul Stephenson singing Captain Of The Loving Kind (These Days, Stockfisch) where his warm and pleasant voice keeps all of its expressiveness, and the guitar enters the spotlight in convincing fashion. It’s a nice full sound picture that clearly keeps its distance from the listener, exactly as one expects. High notes are playful, light and supple, the M3si is never sharp. At the same time when higher frequencies are present they are not suppressed or smoothed. Pamela Michael and Andrew Lawrence King play flute and harp on the high definition recording Garden Of Early Delights (Linn). I listened to this music on much larger Harbeth speakers (Super HL5 plus) with a heavy class A amplifier the night before, using the same converter. The current system is limited in comparison, but the fun factor is the same. The acoustic properties of the studio are less audible but only a little detail is lost. Quiet sounds made by the air blown into the flute are still clear.


M3Si Black Angle Left


I also played Janine Jansen’s interpretation of the Four Seasons (Decca), I chose the three tracks of Summer. It’s unbelievably beautiful music that varies between intense power and great tenderness, the amp has more than enough dynamic range for the job. That beautiful stereo image is also back, reaching well beyond the speakers, spread out to the left and right, using the full height of the listening room. If you ever listen to the M3si and you hear no such image, the recording might be the issue, the source or the speakers, but not the amplifier. Janine’s enthusiasm is palpable, because even cranked up to a high volume level the M3si delivers. With my feet back on the ground, the soundtrack of The Prince Of Tides, composed by James Newton Howard, forms a nice ending. This large orchestral work shows that the M3si is ready for the demands of home cinema world.

Wishes or complaints?
Partly because the M3si needed proper a run-in and partly because the distributor was in no hurry to collect the amplifier I continued to use it for longer than normal. It turned out to be a fine partner to my system, offering a wide open and beautiful sound. In truth I have not been able to discover any real shortcomings, save to mention that the USB input lags when compared with the line inputs. Maybe Musical Fidelity is still more convinced about the quality of CD players compared to streaming. There is after all an M3 series CD player with its own digital inputs. Those willing to invest in ultimate sound quality using music files will have to look for an external DAC, those with an ‘i’ device or a PC to play downloaded files can use the M3si as is, it won’t let you down. The sleek design contributes to the fun so thumbs up for the chic LEDs, they are bright enough to be seen in sunlight but never beam at you in the evening. Wishes or complaints? Not from me this time. The M3si turned out to be a really nice amp, powerful, pure and able to handle all kinds of music at high or low volume settings. More amplifiers should be this useful and handsome.


Power output: 85 Watts per channel into 8 Ohms
THD(+ noise): <0.014 % typical, 20Hz to 20 kHz
Signal to Noise Ratio: >98dB ‘A’-weighted
Frequency Response: +0, –0.1dB, 10Hz to 20 kHz
Inputs: 4x Line Level RCA / Phono, USB – Type “B” socket up to and inc. 24 bit 96kHz USB audio stream, 1x MM Phono input
Phono Input: Sensitivity (nominal): 3mV (suitable for cartridges giving 1.5mV or more including high output MC types)
Signal / noise ratio: >70dB ‘A’-weighted
Input impedance: 50k Ohms
Frequency response: RIAA/IEC ±1dB, 20Hz to 20 kHz
Dimensions – WxHxD (mm): 440 x 100 x 400
Weight (unpacked / packed): 9.2 kg/ 13 kg
Available in silver or black

Price when tested:
Manufacturer Details:

Musical Fidelity Ltd
T +44 (0)20 8900 2866


integrated amplifier & DAC


René van Es

Distributor Details:

Viertron bv
T 00 31 180 618355

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