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If you want a USB-C splitter that keeps USB-C headphones working while your phone fast-charges, choose Marsno USB C Splitter; if you need a USB-C to 3.5mm adapter that lets you plug in regular wired headphones while charging, choose AVMAX USB C.
• Marsno USB C Splitter — biggest strength: a true 1-in-2-out USB-C design with a Realtek DAC and PD 60W (20V/3A) charging, so you can run USB-C headphones and power at the same time. Biggest trade-off: it only accepts USB-C headphones, won't drive two headphones, and passes no video at all.
• AVMAX USB C — biggest strength: a 2-in-1 USB-C to 3.5mm adapter with a 32bit/384kHz DAC and PD 3.0 60W charging that also plays nice with QC, AFC and PPS. Biggest trade-off: the audio side is a 3.5mm jack, not USB-C, and it does no data transfer.
• Pick Marsno USB C Splitter if you've already moved to USB-C earphones and want one dongle that charges and listens.
• Pick AVMAX USB C if your everyday headphones still end in a 3.5mm plug and you want the widest fast-charge handshake.
The Marsno is a splitter in the literal sense: one USB-C male plugs into your phone or tablet, and it fans out to two female USB-C ports — one for audio, one for charging. The audio port is built around a Realtek high-resolution decoding chip, and the charging port runs Power Delivery up to 60W at 20V/3A through an EJ899M chip. Marsno's own notes are refreshingly blunt about the limits: the audio port only takes USB-C headphones, the charging port only charges, and it will not feed two pairs of headphones at once. It also passes no video — no HDMI, no VGA, nothing visual.
So who is this actually for? Someone who has committed to USB-C earphones. If your daily pair is a USB-C set — or you're on a phone like an iPhone 17/16/15, a Galaxy S25/S21, a Pixel 7/6/5/4, or a Sony Xperia with no 3.5mm jack — the Marsno solves two problems with one cable. Long flights, all-day calls, gaming sessions where the battery is draining fast: you plug in the headset, plug the charger into the other port, and keep going. The 5 x 0.98 x 0.2 inch braided body is small enough to leave on the cable, and the metallic grey finish is neutral rather than flashy.
Skip it if your headphones are 3.5mm. There's no analog jack here — this adapter speaks USB-C audio only, so a standard pair of wired earbuds simply won't connect without its own adapter. Skip it too if you want to charge fast with a Quick Charge brick on a newer phone; Marsno explicitly warns QC may not be supported on some recent models, so a PD wall charger is the way to go. And if you expected video out, this is the wrong product entirely.
The AVMAX takes the older, more universal route. One end is USB-C, the other splits into a 3.5mm aux jack and a USB-C charging port. That means the headphones you already own — the ones with the round plug — still work, while your phone tops up at up to 60W over PD 3.0. AVMAX says the charging chip also recognizes QC, AFC and PPS standards, which is a wider handshake than most budget dongles bother with, and it adjusts voltage and current per device rather than pushing a fixed rate.
The audio side is the headline spec: a smart DAC rated to 32bit/384kHz. In plain terms, that's a high-resolution ceiling well above what streaming services deliver, and AVMAX pairs it with noise reduction for a clean, low-distortion signal. Just be aware of the fine print — your phone's audio settings have to cooperate to actually output at that resolution, and the adapter does no data transfer, so it's audio and power only.
It fits you if you're a 3.5mm holdout. Wired IEMs, an older pair of over-ears, a headset you like — all of them plug straight in. The compatibility list is broad, covering iPhone 17/16/15 families, Galaxy S26/S25/S24/S23/S22/S21/S20 lines and Note models, Pixel 10 down to Pixel 6, iPad Pro and iPad mini 6, MacBooks, OnePlus, Huawei Mate and P series, and even a PS5 or Steam Deck. At 2.56 x 0.79 x 0.39 inches it's a stubby little thing that won't snag.
Skip it if your headphones are USB-C — there's no USB-C audio port on this one, only the 3.5mm jack. Skip it if you need to move files while listening, since data transfer isn't supported. And if you wanted a splitter to run two headsets, neither product does that, but the AVMAX certainly doesn't.
• Best for USB-C headphone owners → Marsno USB C Splitter. It's the only one of the two that actually accepts a USB-C audio plug.
• Best for 3.5mm headphone owners → AVMAX USB C. The analog jack is the whole point, and your existing wired gear just works.
• Best for highest audio resolution on paper → AVMAX USB C. Its DAC is rated to 32bit/384kHz versus the Realtek chip in the Marsno, which Marsno describes as high-resolution without quoting a figure.
• Best for fast-charge standard coverage → AVMAX USB C. PD 3.0 plus QC, AFC and PPS is a wider net than the Marsno's PD-only 60W, especially if you own a mix of chargers.
• Best for iPhone 15/16/17 and Galaxy S25 buyers → either, but check your headphones first. Both list these phones; the deciding factor is whether your earphones end in USB-C or 3.5mm.
• Best for calls and mic use → either. Both support microphone and inline controls on the audio path, so voice calls and gaming chat work on both.
• Best for travel and everyday carry → Marsno USB C Splitter. The braided nylon cable and 5-inch length are easier to route from a pocket or bag than a rigid stub.
• Best for warranty length → Marsno USB C Splitter. It carries an 18-month warranty versus AVMAX's 12 months.
In my opinion, the deciding question isn't which adapter is "better" — it's what's already in your bag. If your headphones are USB-C, buy the Marsno USB C Splitter; it's the only one that will physically connect them, and the PD 60W charging plus the longer warranty make it the more reassuring pick. If your headphones are 3.5mm, buy the AVMAX USB C — the 32bit/384kHz DAC and the PD/QC/AFC/PPS charging support make it the more flexible partner for a mixed drawer of cables. Neither is a video adapter, and neither runs two headsets, so don't buy either expecting that.
No. Its audio port is USB-C only, so standard 3.5mm earphones won't connect. If you need a round jack, the AVMAX USB C is the one to look at.
AVMAX rates it for up to 60W PD 3.0 and says it also recognizes QC, AFC and PPS, which covers most Samsung and Pixel fast-charge modes. Use a proper PD charger for the best results.
No. Marsno states plainly that its splitter passes no video of any kind, and AVMAX describes its adapter as audio and charging only. Both are listening-and-charging tools, nothing more.
Both are budget accessories with no price shown here, and prices move around, so check the current price on Amazon before deciding — the button on this page takes you there. Let your headphone plug, not the number, make the call.
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