Musical Fidelity M8xi & M3si Integrated Amplifier Review

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Integrated amplifiers nowadays act more like AV receivers than they do two channel audio components; offering things like Bluetooth, streaming and Dax (audio extenders) and even HDMI. All of these are great features but what are you supposed to do if you don’t want those things?  What if you’re looking for an integrated amp that’s a little bit more simple, maybe even future proof. The Musical Fidelity M8xi and the M3si are such integrators that we will be talking about today.

Click here to check M8xi’s updated price

My first experience with musical fidelity was through their series of amplifiers; specifically the A3 and A308. While exceptionally more expensive than my lowly NAD amplifier that I had at that time. I did see the musical fidelity products as being aspirational, affordable and then I could see myself in time potentially buying them which is more than I could say for the rest of the lines that my dealer carried at that time. 

Sadly, I didn’t buy the musical fidelity products, opting instead for a host of other audiophile purchases, all of which turned out to be horrible investments, but I never forgot just how special those ‘A’ series amplifiers were. My curiosity about musical fidelity never waned which is why we are here today to discuss not one, but two of their integrated amplifiers, the first being the M3si followed by their flagship, the M8xi.

Now the M3si is a purist two channel integrated amplifier and mostly an analogue affair. There is no streaming, heck there’s barely even a DAC! The M three is all about analogue connectivity and it’s amplifier; two things that never really go out of style nor need updating.

Click here to check M3si’s current cost

Musical fidelity’s M series is fast. We opted for the M three si because on paper, it looks to strike the right balance between power practicality and price. It also is stunning. It’s one of the better, more minimal designs in all of the high five. Now, it comes in black, but I especially love it in the light silver which is what we have here.

And if you think it looks familiar or looks like other M series integrated amplifiers for musical fidelity, you’re not wrong, they all share visual cues. Really, they only vary in terms of their height though you do get more power and performance and features as you step up the line.

But the M3si is one of those products that looks decidedly high end; especially when you start to compare it to the looks of its competitors. Well, not a barnburner in terms of features, also not to start stressing in a year wondering whether or not it’s going to get that new firmware update or be rendered obsolete. In order to properly test the M three si, we connected it to a host of analogue components and some not so analogue ones.

For turntable duty, I relied very heavily on my U turn Orbit special as well as the spin deck from Andover audio. I even used our Cambridge Audio; the turntable which uses a moving coil cartridge and has a built in phono preamp. Now it should be noted that the funnel preamp that’s built into the M three si is mainly for moving magnet cartridges though it does have some support for higher output moving coil ones, but in order to test the phono preamp inside the M three, I did only use the U turn audio Orbit special as well as the Andover audio spin deck.

Additional components included our Arylic s50 Pro music streamer. We even connected it to the LG 8k TV via a HDMI to analogue converter box to fully test it’s 85 watts per channel. We also connected it to the Bowers and Wilkins signature towers, as well as the Q Acoustics concept 300 bookshelves and our reference KLipsch heresy Mark fours right off the bat.

If you are familiar with the Bowers and Wilkins signature speakers, you will know that we had one heck of a time finding an amplifier that worked with those particular speakers and one of the amplifiers that did well, the only affordable one, was the musical fidelity M3si. While it may only have a rated power output of 85 watts per channel, one of the things that is most noticeable about its performance is the control and way with which it puts that power down. 


This is an amplifier that sounds far beefier than its specs would lead you to believe. In fact, it exhibits such control over virtually any loudspeaker we connected it to and does so with ease that you would come to expect from costlier components, or more powerful ones. Bass was firm and incredibly textural subtle cues came through more clearly. 

There’s an awful lot of speed in the lower octaves which brings an immediacy to the music down low, listening to bangers like Dua Lipa’s latest through the Concept 300 proved that even though it’s a two way bookshelf loudspeaker, no subwoofer is required for satisfying bass. The mid range is equally nuanced and agile.

This is a fast amp; do not mistake that description as it being lean or forward, it’s neither of those things. It just has an ease with music that makes it immediate and brings out a certain presence, while not live, is definitely more in the room.Vocals are natural in their tambor and inflection, be it male or female.

This really isn’t an amplifier that colours the sound of your loudspeakers, which makes it one of the more neutral affordable integrators we currently have in house. The high frequencies are equally impressive though a little bit smoother and more editorialised in comparison to the bass in mid range. They are still exceptional and they roll off in such a way that would pair nicely with a lot of today’s digital music.

There’s still plenty of air and extension present, not to mention snap and decay. It just lacks that little bit of shimmer of top soundstage wise. The musical fidelity is among one of the best that I’ve heard at this price point. Yes I have heard amps that throw maybe a wider soundstage or a deeper one, but never one as balanced and detailed as this. That ease and control that we spoke about earlier is present and accounted for here, and it really doesn’t matter what genre of music you choose to listen to. You’re going to hear a soundstage as the engineer intended and you are probably going to hear every note just a little more clearly.

Dynamics are exceptional and as I stated earlier, this is one of the few amps that was able to make the Bowers & Wilkins signatures shape up and act right. Now I don’t want you to let that lull you into a false sense of confidence by me saying that it can drive any loudspeaker on the market because it likely can’t. But for 90% of the loudspeakers on the market right now, this amp is more than enough, and even more than enough if you like it loud. 

Apart from its almost total lack of digital connectivity, it’s single USB input notwithstanding, there really isn’t much to fault with the M3si. Well, almost nothing.


It’s remote control is terrible in the opposite of the minimal design chic that you get with the amplifier itself. This remote is so old, I actually think that it’s been with musical fidelity, all the way back to it’s ‘A’ series which is going on 20 years old. And it was bad back then, but it’s a complete and utter letdown today in 2020. 

Thankfully the M three si is so easy to use that I don’t think that you’re going to have to rely on the remote all that much. It’s amazing to me how in 2020, you can have a remote be such an afterthought, especially when you’re pairing it with a product that is well thought out and designed as this one is and yet, that is what has happened here.

This isn’t the only brand that is guilty of this. It is just one of my pet peeves that I have just never understood how so many brands can design such great hardware, and then completely drop the ball when it comes to remotes. 


As far as comparable products go, there are more than a few at this price point, many of which offer more connectivity options but may not be the best in terms of overall amplifier performance. One example of this is the Denon PMA 150 H, it’s stylish, hugely connected and comparable in power to the musical fidelity but I’m still going to give the edge to the M three as I like was for the Marantz PM7000N, and it too, has a host of connectivity options, and even has a very capable amplifier. I’m just going to argue that it’s not as powerful, robust, or as refined, as the musical fidelity is here. 

Now, another amplifier that is worth noting is Cambridge audio’s CXA81. Now that amplifier has a lot in common with the musical fidelity m three, but it does have a slightly warmer, more romantic sound signature that may be what you are looking for if you are coming home to listen to music in order to relax; but if you are looking for refinement and accuracy, you’re gonna find it with the musical fidelity over the Cambridge. 

M3si VS M8xi

We’re gonna have a bit of fun because we really should not be comparing the M3si to the M8xi, and yet there are some similarities here. You can definitely hear a similar approach to sound reproduction out of both units and as a result, the M three si kind of comes off as a scaled down rendition of the M8xi.

Even in terms of styling and materials, there is a family resemblance. The M8xi is only an integrated amp and that its chassis is so large that it enables it to encapsulate a dedicated and isolated preamp, as well as two mono amplifiers in the same cabinet. In other words, it’s basically a separate system in one stylish chassis.

The M three si therefore exhibits a surprising amount of control and finesse. Then it has to be said that the M8xi is the epitome of both in the literal sense. I do not know if I have heard a finer amplifier, than the M8xi, in all of my years of reviewing products. Now I’m not going to break down the individual Sonic traits of this amp because in my opinion, this is what music via digital or analogue is supposed to sound like when played back at the highest level. 

It’s not as if the M8xi has allowed me to hear things I’ve never heard before, it has just enabled me to hear those faint traces of notes or those subtle harmonies anew and it’s brought them forward and presented them to me with undeniable clarity. 

Unlike other amplifiers that simply become louder as you turn them up, the M eight xi becomes more clear. Don’t get me wrong, it can play loud, but it never goes from being loud to shouty. It just builds, like layer upon layer with more volume until the entirety of your room in your system is transformed into whatever the recording says it should be.

The M8xi is absolutely one of the finest two channel integrated amplifiers on the market right now and arguably one of the finest ever made. While not cheap at around $7,000 US, I consider it to be an absolute steal when I compare it to systems that I have had in the past.

Built around things like Pass labs x350 amplifiers, or Mark Levinson’s own reference number 52, monoblocks, and number 526 preamplifier; the latter combination costing well over $60,000, and that was before we even talked about speakers. 

So the M eight xi begs the question of how far are you willing to go, but more importantly, what are you willing to spend for that last five to 10% of performance. Because here’s the truth; It is not seven times better than the M three Si, don’t get me wrong, it is demonstrably better, one of the finest amplifiers on the market.

But for most people in everyday environments with everyday systems and everyday listening levels, the M3si manages to get 70 to 75% of the way there to the M8xi’s performance. So let me just end with this. If you are serious, I mean very serious about the fidelity of your two channel playback, I can think of few products on the market right now that can do what the M eight can at any price, but for the rest of you, and the rest of us, there is the M three Si, which all things considered, might actually be the more impressive, of the two integrated amplifiers.

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