MC331 Tube Integrated Amplifier with DAC, 2 Channel Home Audio Stereo Power Amp for HiFi Bookshelf Speakers/3.5mm Headphones, Vintage VU Meter Preamp with Bluetooth and USB/Opt/Coax/RCA

There are basically two categories of inexpensive audio equipment: "you get what you pay for" and "capable of embarrassing much more expensive equipment". I think Fosi has garnered the reputation at this point to run for president of the latter group. I love this amp. I'm a musician and high quality audio is important to me, so believe me when I say it sounds good. The warmth and quirks of the tubes is very audible. Play music through it before they're fully warmed up (and they do get quite warm) and the sound is harsh and lacking dynamic range. Give it a few minutes and the sound mellows out and the sound stage comes into its own. There's easily enough power to fill a room, and it's sounded full and detailed with every genre. I also really appreciate the style and build quality of this unit. Unlike many other products at this price point, the construction is entirely metal; and not foil-thin metal the flexes under minimal strain. It feels sturdy, thick, and has a decent weight. There's no plastic here (except for the shield on the vu meter and the protection tubes around the vacuum tubes, which I don't mind). Even the knobs on the front are metal, and feel very satisfying in the hand. The connections on the back are also solid, if a bit small and close together. I think banana plugs are pretty much a must on this unit, unless you want to spend 10 minutes "threading the needle". Out of the box, the tubes come separately and you attach them yourself, giving it a bit of a DIY feel. Maybe having to partially assemble the unit yourself heightens the emotional connection. It's not just plug-and-play; you actuay have to spend some time interacting with it before you can use it. The tubes are featured prominently, but the amp makes no obfuscation of the fact that it's a thoroughly modern piece of equipment. There's a minimalist aesthetic here that I appreciate, and it's pulled off much much better than the brands that try to go for a faux-vintage look. The volume knob is doubles as the input selector by pushing it and the power button by pushing and holding for a few seconds. Turning it on or off, either with the power button or the handy remote, the unit gives a satisfying click. The only other controls, the bass and treble knobs, are very functional. The dichromatic amber-on-black is visually pleasing, and the amber lighting around the tubes is actually tastefully done I think. Tubes naturally have a dim glow, but many units (especially cheap ones) feel the need to play this up by covering the tubes in LEDs that usually look tacky. Here, the subtle amber glow accentuates the tubes, I think, rather than obfuscates them. The VU meter is also just fun. I think that's about all I have to say. I'm gonna go back to listening now.

I had heard good things about this manufacturer's amplifiers, and I needed something a little more than a one input amplifier. This integrated amplifier allows you to connect via Bluetooth, USB-C, RCA and optical, allowing me to use this to connect to an Arylic streamer and my PC. I was initially reluctant to purchase something that uses tube technology, since I'm not sure how long they will last. My previous solid state receiver lasted 20 years with no issues until last month when it started getting cross talk issues between FM and other inputs. With the Fosi MC 331 on sale I thought I'd take a chance. My concerns are unfounded so far, since the tubes are only for the pre-amp stage and are easy to insert and replace. I've even come across some suggested tubes that allegedly improve the sound, although the sound with the included tubes is terrific. I'm not crazy about the user interface, since the volume dial is used to adjust the volume, switch between the sources by single clicking, and a power switch, by long pressing. I have some unusual banana plugs that I was unable to use since they are not the usual type but are flexible and intended to be used in the clip type speaker posts but this amp only allows for standard rigid banana plugs and using bare wire to insert into holes under the twist-tight speaker posts. You'll be better off with thinner speaker wire if you don't have rigid banana plugs and need to attach using bare wire, as the 14 AWG speaker wire I use barely fits. Thinner wires are fine for shorter runs, so I wouldn't be worried if this were to power nearby bookshelf speakers, which I suspect will be the most frequent use case for this amp. The built-in Texas Instrument DAC allows this to be connected to my PC via USB-C cable and the improvement over the original Realtek sound from the HP PC and RCA cables was noticeable. Some caveats: the manufacturer provides tube protectors to keep you from touching the glass tubes as they are fragile and get quite hot so don't touch them with the power on. It takes the tubes 15 to 20 seconds to warm up, so make sure to turn the amp on before you sit down to enjoy your music. This amp is tiny and fits easily on the shelf with the shelf speakers, which are 10 1/2 inches tall. By comparison. the receiver this replaced took up all the available shelf space. Have to move some stuff around now with the extra space. This also has a headphone amp, but note that while using the headphone output, the speaker outputs are not available. A remote control is included, but you'll need two AAA batteries, as none are supplied. If I run into any issues with this I'll update the review, but so far very happy with this purchase.

LOOKS amazing! SOUNDS great!! Remote SUCKS! ha ha ha! but then again, I am a bit impatient... This little amp is a joy to listen to! and play with! and look at! It looks so good: small, the VU meter moves a lot, the light is soft, it is a joy to look at, very elegant on the mantle. Sound is very nice; warm, detailed, voices come in as if the singer is there (listen to Norah Jones - Come Away With Me - 24bit/192kHz - Qobuz.com). I hooked up (from my Samsung S22 with Qobuz) an external DAC to it (SHANLING UA4, Moondrop Echo-B, or FiiO KA13 dongle amp) and my speakers Magnat 503's (which are very efficient at ~91) and got very good sound. It can get loud (loud enough to make the dog next door bark, and that furious little thing is ~100 ft away). But the sound quality stays very good and even at loud levels, very loud levels. I have other setups that are Class AB (Arcam SA10 with FiiO K13 R2R, and fed by the WiiM Pro AirPlay 2 Receiver, again via LAN cable and Qobuz). The difference is very minimal and I can tell only because the FiiO K13 R2R architecture leaves a mark on your ears/brain (that thing is so AWESOME!!! of all the entry-level DAC's I reviewed that one I kept. It is better, in my opinion, than ~$2k DAC's. Actually of all the DAC's I tested this one (FiiO K13 R2R) is the best sounding. You'll love Voila by Andre Rieu and Emma). Anyways!! I am getting this little amp for my sister for Christmas. She will not mind the remote latency at all, and she will be so happy at the way it looks. It looks very good, one of the most well designed aesthetics in the audio world. I am getting the "1Mii B06Ultra Bluetooth 5.2 Receiver" for her so she can listen to this thing via LDAC Bluetooth from her phone, as this little amp does not come with any worthwhile codec's. Back to the Fosi Audio MC331 - The REMOTE SUCKS: the remote takes two seconds to recognize you pressed the volume button on it (up or down), if and when it decides to recognize it. And you have to point it directly at the amp, the IR will not bounce off stuff like it does with other remotes. ALL the buttons have a darn-awful latency to them, even the selector. It can get infuriating after a while. I was working on a spreadsheet and wanted the sound just a little lower and instinctively picked up the remote and pressed the volume button, but it took forever to register so I had to take my mind off what I was working on to focus on "is this thing working!!??" It pisses you off after a while. And yes, some of the sound disappeared when I turned it very low (almost silent); and no, "that is expected, dufus!" because I get that, but on the other systems at that very low level ALL the sound comes across-the-board at very low volume, not just some of it. Highly recommended! Just fix the remote Fosi!! :-) :-) another little thing... it will not work with a higher-end power supply. I tried another Fosi power supply on it and it will not even turn on, so you are stuck with the power supply it comes with. Not a problem, but in case you were wondering "what if..." you added a better power supply?? No, it will not work. You are stuck with the 24V it comes with.

A friend purchased this amp for a standalone turntable system, and it sounded great with the records I heard so I purchased one to use as well, even though I already had my turntable connected to my Emotiva receiver (via a Fosi tube pre-amp, which has been great!). The look of the unit along, adjacent to the tube preamp, was very nice, and the sound was almost as clear as through the Emotiva, but I noticed that during certain sounds (applause on Sgt. Pepper's, and various times on Pink Floyd Animals), the sounds would run together and become more like static. I reconnected my receiver and confirmed this did not happen with it. As much as I liked the look and (generally) the sound, these faults made me decide to return the unit. But for a standalone system, this paired with a Fosi tube preamp looks great and would perform well the majority of the time.

I bought this Fosi audio amplifier looking for a compact and affordable option, and it exceeded my expectations. The sound quality is excellent for its price range: very good definition, clear detail, and a balanced reproduction of lows, mids, and highs. It is easy to set up, works reliably, and drives the speakers very well considering its size. The build quality feels solid and the overall performance is more than satisfactory. I definitely recommend this amplifier to anyone looking for great sound without spending too much. Outstanding value for money.

A simple tube based power amplifier that has a Bluetooth receiver that can pair with up to 10 devices. It will only receive from one device at a time, so you need to turn off the Bluetooth device on are not trying to pair with when switching between Dec, but this is to be expected. I have used it with a Bluetooth enabled turntable, and a couple of iPhones. All worked as expected. I also tried a very inexpensive Bluetooth enabled pocket cassette player, and would not pair. So, your mileage may vary. Sound quality is decent, with pretty good bass. Ultimately this is determined largely by the speakers, so the better your speakers, the better the sound. It has a Bass and Treble control, which work, but obviously not as good as a multi channel equalizer. Build quality: Seems good. All the parts were provided and packed properly. I had no difficulty assembling the amplifier, which just involved plugging in the two tubes, screwing in the tube heat protectors, and connecting the cables. Power: The amplifier is rated at 105 watts per channel, into a 4 ohm load,, which is more than enough for any small to medium sized room. I noticed no distortion at any of the sounds levels I was using. The price: at $116 with a small running discount, this amplifier is easily worth the price. You get what you pay for I guess. Overall I am happy this little amplifier. Recommended!

Sounds incredible. It was easy to hook up, with a lot of input options. For the price, it made an immediate and significant improvement. It's clear, and the soundstage is spacious. I'm really happy with it so far, and I'm not using fancy headphones (yet).

I purchased this unit for my TV, but the optical input did not work and produced strange sounds. I thought the cable was faulty, so I bought a new one at Best Buy, but the issue persisted. While Bluetooth and sound quality were excellent, the unit ultimately didn't meet my needs.