[Listening test] Lonpoo LP42MX - passive minimonitors

Product: Lonpoo LP42MX - 2-way bookshelf loudspeakers
Manufacturer: Lonpoo - China
Suggested retail price: €/$95/pair, depending on offers and shipping
Reviewer: Lucio Cadeddu - TNT-Audio Italy
Reviewed: December, 2025

A few months ago, I reviewed the new LP42M active mini-speakers, with rather disastrous results. The issue was entirely due to their internal electronics and DSP, which completely undermined the speakers' performance. In fact, with a small, reversible, zero-cost 10-minute modification, I was able to bypass the internal amplifier, turning the LP42Ms into passive speakers that suddenly - almost magically - started to sound great. So, I asked Lonpoo whether it might be a good idea to sell the LP42M directly without the awful built-in electronics. They agreed, and thus the LP42MX was born. To avoid any specially prepared (i.e., improved) review samples, I bought them anonymously on-line. Lonpoo's naming scheme has never been what you'd call logical. The original LP42 was joined by the active LP42X, so I assumed the X indicated the active versions. But no - the next active models were called LP42M, and now these passive ones bring back the X. In short, it's a total mess. I imagine the change in finish, and even in the colour of the drivers, was done to clearly distinguish them from the active LP42M units they're derived from.

A closer look

I was surprised when I first saw them, because the (faux) dark-wood cabinet finish had been replaced with a black oak finish (like the original LP42s), and the woofer's aluminium diaphragm had changed from copper to silver colour. I initially feared they had swapped the drivers entirely. After opening the speakers, however, I can confirm that the drivers are identical in every respect (4" aluminium woofer and 1" dome tweeter). Even the tweeter's filtering and attenuation remain unchanged.

The internal damping material and wiring - complete with the usual foam sleeves around the cables to prevent vibration - are also the same. The only difference lies in how the drivers are connected to the binding posts: in the LP42Ms, two pairs of wires come from the binding posts, one for the woofer and one for the tweeter, which would have made bi-wiring very easy to implement by simply desoldering the leads and adding a second pair of input terminals. In these LP42MX units, however, a single wire from the binding posts feeds the woofer, and the tweeter is then connected directly to the woofer's terminals. This was likely done to streamline assembly, reduce internal wiring, or shorten the signal path. I suspect the first reason, as this is clearly a cost-sensitive design where every cent matters.

Biwiring is still perfectly possible, though: just desolder the wires that run from the woofer to the tweeter and route them to a second pair of input binding posts. I'm not a fan of biwiring, though.

The package, in addition to a decent user and installation manual, contains a reasonably thick speaker cable and some felt pads to place between the speaker and its support base.

A note on the lack of filtering on the mid-woofer

The woofer, following LP42 tradition, uses simple mechanical filtering (i.e., it plays as high into the frequency range as its natural response allows). This has horrified YouTube “experts” and even more knowledgeable Facebook-group gurus, unaware that many high-end speakers have used - and continue to use - the same approach for decades. Diapason, for instance, grandly calls it Direct Drive, because the woofer is connected directly to the amplifier with no filter or crossover. The GrandiNote MACH8P employs the same solution. Long before these premium models, several AR speakers (AR7, AR18, and others), the legendary Epicure EPI100, the Pioneer HPM900, the Polk Audio Model Nine, and many designs from Epos and Mordaunt-Short all worked exactly the same way. But back then, today's YouTube reviewers either weren't born yet or were still listening to the musical mobiles hanging over their cribs - perhaps explaining their current analytical abilities.
For their cultural enrichment (assuming they can read, given their preference for images), here's what Diapason designers state on their website for greater clarity:
“The Direct Drive principle is simple: the natural frequency response of the mid-woofer allows for direct connection to the rear connectors, without the use of a low-pass circuit. The result is immediately perceptible: exceptional speed and control in the low frequencies.”
A similar claim can be found on the GrandiNote website: “Nine woofers, pure sound - no crossovers, no compromise.”
For the sake of fairness, those who mocked the LP42s for using this same principle should direct the very same criticism toward Diapason, Epos, Mordaunt-Short, and even GrandiNote - manufacturers of very expensive high-end speakers. Of course, their drivers are of far higher quality, but there is nothing surprising or “scandalous” about relying on a woofer's natural low-pass behaviour. Now you know: designers far more skilled than you, working on projects unconstrained by budget, have chosen the very solution you find so incomprehensible. Get over it. And learn a bit of Hi-Fi history - it will only do you good.

Returning to the small and modest LP42MX, they continue to use a rear-firing bass-reflex system, in keeping with LP42 tradition. The gold-plated input terminals accept banana plugs, spades, and bare wire. The cabinet is reasonably robust, made from adequately thick MDF.

For the record, I weighed them: the old LP42M slave - that is, the passive speaker - weighs 40 grams more than this LP42MX. I believe this is simply normal manufacturing variance in the cabinet, since the drivers are exactly the same.

Evolution of the species - listening notes

These LP42MX units cost about €10-€20 less than the active LP42Ms. Frankly, I was hoping for a greater price difference, considering they omit all the electronics: the amplifier, DAC, Bluetooth module, tone controls, and even the remote control. Still, their price is roughly in line with the original first-generation LP42s, so it's understandable.

Since I still have the LP42Ms I modified into passive speakers, as well as the original LP42s, it's time for a direct comparison. Keep in mind that in the LP42M, the electronics - even when disconnected - occupy part of the internal volume of one of the two speakers. This means the two speakers are not identical, creating an asymmetry that may slightly affect the sound.

After some 10-20 hours of mandatory break-in (do not judge them right out of the box!!!) the sound is exactly as I remembered: excellent bass - now symmetrical between the left and right channels - and a more balanced mid-high range overall, noticeably better than the first-generation LP42s. The absence of electronics in one speaker is immediately noticeable in the LP42MX, as the left and right units now sound perfectly identical. Moreover, because one of the original LP42M speakers effectively gains additional internal volume once the electronics are removed, you also get a bit more low-frequency extension, at least on that channel. However, since bass is largely omnidirectional, the overall effect is that these new LP42MXs deliver even better, fuller, and more present low frequencies.

Not only that, but the mid-high range - particularly vocals - also improves slightly. The electronic board previously housed inside one of the speakers likely introduced some colouration and resonance. After all, the circuit board includes plastic and metal components that can contribute unwanted resonances to the sound. So yes, these LP42MXs sound genuinely convincing. The stereo image also benefits from the restored symmetry between the two speakers, appearing wider, deeper, and more focused.

Although I have already compared the passive'd LP42Ms with the original LP42s, I decided to repeat the test with the LP42MXs. Let me emphasize again that these are two entirely different speakers, with different drivers and a significantly different cabinet. Beyond the larger internal volume, the LP42MXs no longer feature the sloped baffle (see the comparison photo below). Their weight has also changed substantially, increasing by a full 38% - from 1.688 kg to 2.328 kg per speaker.

Listening to them head-to-head confirms the differences I already observed with the modified LP42Ms: an overall more balanced sound, less harsh in the mid-highs, with stronger and more extended bass (they can now be placed farther from the rear wall), and a wider, deeper 3D sound-stage. The only area where the older LP42s perform slightly better is midrange dynamics, where certain percussion instruments sound a bit cleaner and quicker - though not more powerful. At the same distance from the back wall, the three-dimensional image is clearly in favour of the LP42Ms.

Of course, since these are very small and inexpensive speakers, it's perfectly normal for them to struggle with demanding music - especially tracks rich in deep, punchy low frequencies. In such cases, just as with many more expensive bass reflex speakers, the rapid airflow through the reflex port can produce unwanted noises. If you enjoy listening at high volumes (above 90 dB), be sure to keep an eye on the excursion of those small woofers!

Conclusions

I'm glad Lonpoo took this reviewer's criticisms seriously, and I can only acknowledge a level of humility and adaptability that is rare among Western audio companies. Whenever we've given a Western product a negative review, the manufacturers and designers have taken offence, reacted with visible irritation, and, unsurprisingly, stopped sending us any further products. There are many reasons why Chinese products are creating serious challenges for Western industries, but mental flexibility and the willingness to learn from one's mistakes are certainly among the most important. Maybe - just maybe - we have something to learn.

What else can I say about these LP42MXs, other than that they are a substantial improvement over the LP42s? At this point, I would recommend that Lonpoo give the older model LP42 a well-earned retirement. It simply no longer has any reason to exist when the LP42MX is available at the same price. Finally, I'd love to see an active version of these speakers, using the electronic board of the first series of LP42X.

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Lonpoo LP42MX - mini-monitors

Evolution of the species

A closer look

A note on the lack of filtering on the mid-woofer

Evolution of the species - listening notes

Conclusions