Quloos, a well-known Chinese brand, is celebrated for its wide array of high-quality audio products. My introduction to the brand came through MUB1, a dac/amp unit. Prior to experiencing this little wonder firsthand, I came across commendations for this compact device and decided to dig deeper into both the product and the brand itself. Among their notable offerings from the brand is the QA390LE, which has also received acclaim for its exceptional quality from various people.
Concept Kart, a local online store in India, sent me the MUB1 for an audition. MUB1 sells for nearly 500 USD. It can be bought here.
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Rating Criteria:
I want to lay out my rating criteria before we start off. For me, the primary criterion for evaluating audio gear is its intrinsic value rather than its price tag. A higher price doesn't always correlate with superior quality, and similarly, a low-priced product can give enough listening pleasure for it to be called outstanding. I consider the build, features, and, most importantly, the impact on the listening experience. The fundamental purpose of audio gear is to enhance the listening experience. So for me, this degree of enhancement in the listening experience is a key determinant in rating a product.
Rating below 4: I really won't be posting reviews of such items unless someone has asked for them.
Rating of 4: The product is good, and some users may find it more satisfactory, but it does come with a few caveats, such as price, fit, etc.
Rating of 4.5: The product is excellent and comes with an easy recommendation, reflecting its high quality and overall positive attributes.
Rating of 5: This product can be deemed groundbreaking, a trendsetter, and an eye-opener and deserves a spot on everyone's list due to its exceptional features and outstanding performance.
Product Features:
MUB1 boasts a plethora of features, rendering it an exceedingly valuable device. It encompasses all the essential functionalities one could think of within its price range. To begin with, it harnesses the power of four CS43131 DAC chipsets, for delivering exceptional sound quality characterized by high resolution and refined tones, along with an impressive signal-to-noise ratio.
Inputs: There is a USB type-C data source where you can connect your devices for listening. The other USB-C port is for charging. It also takes data input via Bluetooth, supporting the 5.0 BT protocol. The BT connection uses some advanced features to stream with decent sound. The BT connection is quite strong and does not drop.
Gains: There are 4 types of gain modes. Low, Medium, High, and Super High gain modes. For iems, high gain mode is more than enough. One can use super high gain with more power-hungry headphones as the output is nearly 3–4 times that of high gain.
Filters: MUB1 offers five different types of filters. While these filters have quite subtle differences, it's good to have options. I used the MUB1 mostly with the NOS filter. Its the most relaxed of all.
Outputs: There is a 3.5mm and a 4.4mm balanced output. The 4.4 balanced output can be set to line out. There is a 3.5 mm optical or coaxial SPDIF digital output too.
Design: MUB1 is quite compact and has a very sleek design factor. It is very lightweight, and its dimension is not an issue when carrying a smartphone. The build feels quite premium, and the device gives a good, solid feel when you hold it. All the functional buttons are on the right side of the device, and the lower side has input and output ports.
Battery: There are separate charging and data slots. For charging, it takes a 5V/2A power supply. The battery life is very decent and can go up to nearly 8 hours on the balanced output. I could not time the battery life, though. To give a good and long life to the battery, there is an option where, when you connect the device to a charger, you can bypass the battery and power the MUB1 directly from the charging port.
Sound Analysis:
MUB1 is a little powerhouse with a very impressive sound and great tonality. The sound is warm and smooth, with some decent bass presence, a sweet midrange, and controlled highs.
The bass on MUB1 is quite decent. Its well layered and has a good texture to it. The subbass has a good body and depth. The bass is tight and precise, with a good impact, and does not intrude on the higher frequencies.
The midrange has a very natural feel, and there is a nice tonal weight to it. The mids are sweet, as per my liking, and the resolution is very decent. Both male and female vocals have good texture and sound quite full. Midrange instruments like piano, string, etc. have decent weight and extension. The upper mids have a good amount of energy and do not get shouty at all. There is no thinness in the upper mids.
The upper frequency is quite controlled and smooth. There is no sharpness or unwanted peakiness, making it ideal for longer sessions. There is good detailing and extension. However, the sense of airiness is not quite pronounced.
In terms of technical aspects, MUB1 performs above average. The soundstage is not as wide but is not even intimate. The depth is quite decent. The separation of instruments in complex musical passages is very decent, and there is no congestion.
Comparisons and pairings:
The only other similar device I could compare the MUB1 with was the Earmen Angel. Angel is more powerful than the MUB1. It hosts an ESS DAC, ES9038Q2M chip. Angel has a neutral sound signature with a hint of brightness. The soundstage on Angel is wider than that of MUB1, and the depth is almost similar.
The natural and organic tonality of MUB1 is more to my liking than the analytical and rather cold signature of Angel. Angel pairs well with warmer iems and adds a sense of airiness. Angel can drive some power-hungry headphones and iems quite well where MUB1 can lack a bit. Angel does not have Bluetooth. Also, MUB1 has buttons to pause, play, and skip tracks, which are not there in Angel. So, in terms of usability, MUB1 can appeal to a lot of people.
Pair up:
64Audio Fourte: I absolutely love how MUB1 handles the Fourte. Its controlled and refined highs create a perfect synergy with the Fourte's nearly-bright character. Mids sound sweeter on the MUB1. The mids are rendered with a delightful sweetness on the MUB1. Personally, I refrain from using the Fourte with Angel as it tends to increase its brightness. With Fourte, there is a slight static hiss likely due to Angel's higher power output. However, I really wish that headstage was a bit better with the MUB1. I found it limiting the true potential of Fourte. I used the NOS filter for the Fourte, which dealt with the upper frequencies the best.
Kinera Verdandi: Verdandi is a power-hungry iem and scales quite a bit with a powerful amp section. MUB1 handles the Verdandi really well; however, the Angel does more justice to it. On Angel, the Verdandi sounds more open, and the headstage is better, thus creating a more expansive audio experience. The output on Angel shows a good sense of airiness, with improved bass impact compared to MUB1.
Among the less power-hungry iems, my preference leans strongly towards MUB1. Its natural tonality significantly enhances its musical character. One reason to avoid Angel with sensitive iems is because of the static hiss in the background. Angel performs really well with iems having a warm signature and higher power demands; otherwise, it tends to sound overly analytical in many instances.
Conclusion:
The MUB1 stands out as an exceptional device, offering a comprehensive range of features within its compact form. It sounds amazing. It has a great battery life. It is powerful enough to fire up most of the iems and decent-sized cans. MUB1 effectively renders any potential use case for a dongle, especially the more expensive ones, obsolete. While its price may be higher compared to most dongles, its unparalleled performance justifies the investment. In my opinion, no other dongle can match the exceptional sound quality of the MUB1. It can also give a good fight to some more powerful dac/amps. I cannot find anything that is missing with the MUB1. It gets a solid recommendation from me.
A true 5/5 device. 
