In our workshop, we have a beautiful vintage amplifier from the 70s. It has a warm, rich sound that modern equipment often struggles to replicate. Its fatal flaw? It’s an analog island in a digital world. For years, connecting a phone meant wrestling with a tangle of 3.5mm-to-RCA cables, a solution that felt clumsy and restrictive. We wanted the freedom to stream our high-resolution playlists from across the room without sacrificing the character of our cherished gear. This is a common frustration for anyone who loves classic hi-fi, has a great pair of powered speakers without wireless capabilities, or simply wants to build their own custom audio solution. The alternative—replacing beloved equipment—is often expensive and unnecessary. We needed a bridge, a simple, high-quality, and affordable way to inject modern Bluetooth convenience into classic analog hardware. This quest led us directly to the world of DIY audio components and, specifically, to a tiny board with a big promise: the HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module.
- Power supply: You can directly use the MICRO USB Android cable 5V for direct power supply, or you...
- Audio output: The earphone can be directly connected to the 3.5mm audio interface, or it can be...
Before You DIY: What to Look for in a Bluetooth Audio Receiver Module
A Bluetooth audio receiver module is more than just an item; it’s a key solution for audio liberation. Unlike a full-fledged AV receiver that acts as the central hub for a home theater, these tiny modules serve a singular, vital purpose: to receive a wireless digital audio stream and convert it into a clean, analog signal that any amplifier can understand. They are the missing link for countless projects, enabling you to build custom portable speakers, upgrade a car stereo, or, as in our case, modernize a vintage hi-fi system. The main benefit is unlocking the potential of existing equipment, saving it from obsolescence and saving you a significant amount of money in the process.
The ideal customer for this type of product is someone with a spark of curiosity and a desire to create. If you’re a hobbyist, a maker, a tinkerer, or simply someone who isn’t afraid to pick up a soldering iron to solve a problem, this module is for you. It’s for the person who sees an old radio at a thrift store and thinks, “I could make that a Bluetooth speaker.” Conversely, it might not be suitable for those who want a polished, plug-and-play consumer product with a remote control, multiple inputs, and a user manual. If you’re looking for an all-in-one box to power your entire living room sound system without any hands-on work, you would be better served by a traditional stereo or AV receiver.
Before investing, consider these crucial points in detail:
- Dimensions & Space: These modules are incredibly small, but your project’s enclosure is finite. You must account for not just the board itself, but also its wiring. Consider where you will route power cables (to the Micro USB, 5V, or VBAT pins) and the audio output cables (from the 3.5mm jack or L/R/GND solder pads). Proper planning ensures a clean, professional-looking final build.
- Capacity/Performance: The core of the module’s performance lies in its Bluetooth version and codec support. The HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module uses Bluetooth 4.2, which offers reliable connectivity and low power consumption. Crucially, its support for lossless formats like FLAC and WAV means it can deliver audio quality far superior to standard SBC-only modules, provided your source device and files are up to the task.
- Materials & Durability: As a bare printed circuit board (PCB), its durability depends entirely on your handling and installation. The quality of the solder mask, the clarity of the silk-screened labels, and the integrity of the copper pads are paramount. While robust for what it is, it’s vulnerable to static electricity before installation and excessive heat during soldering. Careful, methodical work is the key to its longevity.
- Ease of Use & Maintenance: Post-installation, its “use” is seamless; it pairs just like any other Bluetooth device. The real challenge is the installation itself. For those comfortable with soldering, it’s a straightforward task. For novices, the small solder pads can be intimidating. Long-term maintenance is virtually zero, but a secure installation, free from potential short circuits, is essential for a “set it and forget it” experience.
This little module is a gateway to custom audio, but it’s a component, not a final product. Understanding its place in the wider audio ecosystem is key.
While the HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module is an excellent choice for DIY projects, it’s always wise to see how it stacks up against the competition in the broader receiver market. For a broader look at all the top models that offer a complete, out-of-the-box solution, we highly recommend checking out our complete, in-depth guide:
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- Amplify and enjoy your home audio experience in the comfort of your home.Frequency band : 2,400 MHz...
- Advanced circuitry design.Speaker selector for 2 systems. Input Sensitivity (CD): 500 MV/47k...
Unboxing the Trio: A First Look at the HiLetgo M28 Module
The HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module arrives in a simple anti-static bag, containing not one, but three of these diminutive boards. This multi-pack approach is immediately appreciated; it lowers the stakes for a first-time project and provides spares for future audio adventures. Our first impression upon handling the board is just how tiny and tidy it is. Each component is neatly surface-mounted, and the PCB itself feels solid. The silkscreen labeling is crisp and clear, precisely marking the essential connection points: VBAT and GND for battery power, 5V and GND for regulated power, and L, R, and AGND for the left, right, and audio ground outputs. This clarity is a godsend for any DIY project, minimizing the chances of incorrect wiring. The inclusion of both a Micro USB port for power and a 3.5mm stereo jack for audio output makes initial testing incredibly simple, allowing you to verify its function in seconds before committing to a permanent, soldered installation. It’s a thoughtful design that caters to both beginners and experienced makers.
Key Benefits
- Exceptional value for money, sold in a convenient 3-pack
- Impressive audio fidelity with support for lossless codecs (FLAC, WAV, APE)
- Highly flexible power options (Micro USB, 5V DC pins, or 3.7V Lithium battery)
- Dual audio outputs (3.5mm jack and solder pads) for versatile integration
Limitations
- Line-level audio output has low gain, requiring an amplifier
- Soldering pads are small and can be challenging for inexperienced users
In the Workshop: A Performance Breakdown of the HiLetgo M28 Module
A component’s true worth is only revealed on the workbench and in the final build. We put the HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module through a series of rigorous tests, from initial breadboarding to final installation in our vintage amplifier project, to assess every facet of its performance. We analyzed its installation flexibility, its core audio quality, its wireless stability, and directly addressed the user feedback we’d seen regarding its output volume. The results were, for the most part, deeply impressive for a module at this price point.
Installation and Power Flexibility: From Breadboard to Final Build
The genius of the M28 module lies in its accessibility. Our testing began in the simplest way possible: we powered the board with a standard Micro USB cable connected to a phone charger and plugged a pair of headphones into the 3.5mm jack. Within 30 seconds, we were paired to our smartphone and listening to music. This plug-and-play capability is fantastic for immediate verification and prototyping. It allows you to confirm the board is working perfectly before you even heat up your soldering iron. This is a feature that really sets it apart in the DIY space.
Moving to a permanent installation, the module’s flexibility shines. We tested both primary power options. First, we used a simple buck converter to step down a 12V supply to a stable 5V, connecting it to the 5V and GND pins. This is the ideal setup for projects powered by a larger DC source, like a car or a home-built amplifier. Second, we connected a 3.7V single-cell LiPo battery to the VBAT and GND pins, the perfect configuration for a portable Bluetooth speaker. In both scenarios, the module powered on instantly and performed flawlessly. This versatility means a single pack of these boards can be the heart of a wide array of different audio projects.
Now, for the soldering. We can confirm the user feedback that the pads are small. They require a steady hand, a fine-tipped soldering iron, and ideally, some flux to ensure a clean connection. We didn’t find it overly difficult, but a complete beginner might need to practice on a spare board first (another reason the 3-pack is so brilliant). Once soldered, however, the connections for both power and the L/R/AGND audio output were solid and reliable. The design thoughtfully provides everything you need for a robust, permanent integration into almost any audio device you can imagine.
Audio Fidelity and Lossless Playback: Does It Live Up to the Hype?
This is where the HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module truly punches above its weight. Frankly, we were skeptical that a module this inexpensive could deliver on its “lossless” promise. We wired its audio output to a trusted TPA3116-based Class D amplifier connected to a pair of bookshelf speakers we know intimately. The difference in audio sources was immediately apparent. Streaming a standard 320kbps MP3 from Spotify sounded good—clean, clear, and perfectly acceptable for casual listening. There was no discernible hiss or digital noise, a major victory in itself. As one user noted, we also found it didn’t require a ground loop isolator, which is a common and frustrating necessity with many other cheap Bluetooth modules.
Then, we switched to a local source, playing a 24-bit/96kHz FLAC file of a well-mastered jazz track. The change was significant. The soundstage opened up, stereo separation was more defined, and the subtle details in the cymbals and acoustic bass came through with a clarity we did not expect. The M28’s decoder was clearly doing its job, passing a rich, detailed signal to our amplifier. While Bluetooth 4.2 itself is the bottleneck and cannot transmit true hi-res audio, the module’s ability to decode high-quality local files means the source material isn’t being unnecessarily compressed before transmission. For anyone serious about getting the best possible sound in their DIY project, the lossless support on the HiLetgo M28 is a non-negotiable feature.
Bluetooth Connectivity and Real-World Range
A wireless audio module is useless if the connection is finicky or short-ranged. We found the M28 to be both simple and robust in this regard. The pairing process is as straightforward as it gets. Upon power-up, the onboard blue LED flashes quickly, and the device appears in your phone’s Bluetooth menu as “M28” (or M18/M38 depending on the batch). It connects almost instantly. A great feature we tested and confirmed is its auto-reconnect capability; once paired, it will automatically connect to the last-used device whenever it’s powered on and in range.
The manufacturer claims a range of “up to 20 meters” in an open environment. In our tests, we found this to be a realistic, if optimistic, figure. In a clear line of sight across our workshop, we maintained a perfectly stable, skip-free connection at about 15-16 meters (around 50 feet). Introducing a single interior drywall partition reduced this effective range to about 10 meters (33 feet), which is still more than enough for single-room or even multi-room listening in most homes. The connection only started to break up when we put a second wall between the source and the receiver. The performance is solid, reliable, and more than adequate for the vast majority of DIY applications.
Addressing the Achilles’ Heel: Output Volume and Amplification
One of the most crucial pieces of user feedback we encountered was a complaint about low output volume. We can definitively confirm this observation, but it’s essential to frame it correctly: this is a characteristic, not necessarily a flaw. The HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module produces a standard, line-level audio signal. It is not designed to drive speakers or even low-impedance headphones directly. Its output is meant to be an input for a separate power amplifier.
When we connected it to our amplifier, we did notice that we had to turn the amplifier’s volume knob higher to achieve the same listening level compared to other sources like a DAC or a CD player. For example, a comfortable listening volume might be at the 11 o’clock position for a CD player, but we needed to turn it to 1 o’clock for the M28 module. The sound itself was clean and distortion-free; it just had less initial gain. This is a critical expectation to set. If you buy this module expecting to wire it directly to a pair of speakers, you will be disappointed. But if you understand that it’s the “pre-amp” stage of your audio chain—the component that feeds the signal to your “power amp” stage—then its performance is exactly as it should be. For any project, from a portable speaker to a home stereo upgrade, you must pair this module with an appropriate amplifier board to get room-filling sound.
What Other Users Are Saying
Our findings are strongly corroborated by the experiences of other DIY audio builders. The consensus is overwhelmingly positive, especially concerning the module’s core value proposition. One user perfectly summarized the general sentiment, calling the boards “great” and praising their “really good sound quality.” They specifically highlighted a major technical win: the lack of ground loop hum in their setup, a testament to the board’s solid engineering. They rightly concluded that it offers “fantastic value for money.”
However, the feedback also provides a balanced perspective. The same user cautioned that the soldering “can be a little tough” for those with less-than-perfect skills, a point we validated in our own workshop tests. This serves as fair warning for absolute beginners to proceed with care. Another piece of critical feedback pointed to the module’s primary characteristic: the output volume. A user noted they “could not get a high volume output” and had to maximize their phone’s volume. This aligns perfectly with our expert analysis that the M28 provides a clean but unamplified line-level signal that absolutely requires a separate power amplifier to drive speakers effectively.
Clash of Categories: HiLetgo M28 Module vs. Full-Size AV Receivers
It’s important to understand that the HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module exists in a completely different universe from traditional home audio receivers. The M28 is a component for the hands-on creator, a tiny, specialized tool for adding wireless functionality to a larger project. If you’re looking for a complete, all-in-one, high-power home theater solution and prefer a remote control to a soldering iron, you need to explore full-featured AV receivers. These offer a polished, plug-and-play experience that the M28 isn’t designed to provide. Here’s how it compares to some powerful alternatives.
1. Onkyo TX-NR7100 9.2-Channel AV Receiver
- STATE OF THE ART ROOM CORRECTION: Dirac Live take the room out of the equation, automatically...
- ULTRA CONNECTED: Offering 9 channels of processing with three HDMI-out options, the TX-NR7100 AV...
The Onkyo TX-NR7100 is a home theater powerhouse. This is a full command center for a sophisticated surround sound system, boasting 9.2 channels of amplification, 100 watts per channel, THX Certification, and advanced room correction with Dirac Live. It handles 8K video switching, network streaming, and multi-room audio. Someone would choose this over the M28 module because they are building a dedicated home cinema and need a single box to power multiple speakers, switch between various video sources (like a Blu-ray player and gaming console), and deliver an immersive cinematic audio experience. It’s a finished, feature-rich consumer product, not a DIY component.
2. Denon DRA-900H 2-Channel Stereo Network Receiver
- DYNAMIC AV RECEIVER - The Denon DRA-900H Stereo Receiver, a 2.2-channel 8K AVR delivering 100W/Ch,...
- EXPERT SOUND ENGINEERING – Denon's acclaimed high-current amplifiers with their use of Hi-Fi parts...
The Denon DRA-900H is a modern take on the classic stereo receiver, designed for the two-channel audio purist who also wants modern connectivity. It combines a powerful 100-watt-per-channel Hi-Fi amplifier with extensive networking capabilities via HEOS, allowing you to stream from popular services, listen to internet radio, and integrate into a multi-room audio system. It also includes multiple HDMI inputs for video sources. A user would opt for the DRA-900H if their goal is a high-quality, dedicated music listening setup with the convenience of network streaming and the ability to connect a TV, without the complexity of a full surround sound system. It offers amplification and source switching in one elegant package.
3. Denon AVR-X2800H 7.2 Ch Receiver
- IMMERSIVE 3D AUDIO, GEARED FOR 8K - Featuring 8K/60Hz pass-through, the Denon receiver 7.2-Ch...
- GET THE MOST OUT OF YOUR 8K TV - Enjoy the highest quality 3D audio and video with HDCP 2.3 & eARC...
The Denon AVR-X2800H sits comfortably in the middle ground, offering a robust 7.2 channel surround sound experience perfect for most living rooms. It supports 8K video, Dolby Atmos, and DTS:X for immersive, three-dimensional audio, alongside the same powerful HEOS wireless streaming platform found in its stereo sibling. This receiver is the ideal choice for someone who wants to create a compelling home theater experience that’s also great for music. It balances advanced features with user-friendliness, providing a comprehensive solution for movies, gaming, and music that the HiLetgo module, as a simple receiver component, could never fulfill on its own.
Final Verdict: An Essential Component for the Modern Audio Tinkerer
After extensive testing, the HiLetgo M28 Bluetooth 4.2 MP3 Audio Receiver Module has earned a permanent place in our workshop components drawer. It is not a product for the casual consumer seeking a plug-and-play box. It is a brilliant, highly effective tool for its intended audience: the makers, hobbyists, and audio enthusiasts looking to affordably and effectively add high-quality wireless audio to a custom project. Its primary strengths are its incredible value, surprisingly excellent audio fidelity thanks to lossless codec support, and wonderfully flexible power and output options.
Its weaknesses are simply characteristics that must be understood before purchase. It requires some basic soldering skills for permanent installation, and its line-level output signal must be paired with an appropriate amplifier to achieve significant volume. If you understand these two points, you will be delighted with its performance. For breathing new life into vintage gear, building a portable speaker from scratch, or any number of other audio projects, the M28 is an undisputed champion. If you’re ready to start your next audio adventure, we wholeheartedly recommend it. Check the latest price and availability to get started.