We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-19 · 8 min read · Independent comparison
If you want a wired, closed-back studio monitor headphone with a full set of pro accessories and a tunable, isolation-focused design, choose Superlux HD661; if you need a modern studio headphone bundled with a USB-C to 3.5 mm adapter for today's phones and laptops, choose OneOdio Monitor 60.
• Superlux HD661 — biggest strength: A genuinely studio-oriented spec sheet: 40 mm neodymium dynamic drivers, 68Ω impedance, 102 dB sensitivity, and a 10 Hz–20 kHz range, plus two cables, a gold-plated adapter, a cable clip and a pouch in the box.
• Superlux HD661 — biggest trade-off: It's a purpose-built wired monitoring tool. There's no adapter for USB-C devices, and the 68Ω load asks a bit more of weak phone outputs than a low-impedance consumer pair would.
• OneOdio Monitor 60 — biggest strength: It's positioned as a professional studio headphone for mixing, mastering and DJ work, and it ships with a USB-C to 3.5 mm adapter so it plugs straight into modern phones and laptops.
• OneOdio Monitor 60 — biggest trade-off: The published spec detail is thin. You get the positioning and the adapter, but not the impedance, sensitivity or frequency figures that a spec-driven buyer would want to compare directly.
• Who each is for: Superlux HD661 for the home-studio engineer or live monitor who wants documented specs and a full accessory kit. OneOdio Monitor 60 for the modern listener or mobile creator who needs one headphone that works with both a 3.5 mm jack and a USB-C port.
The HD661 is the more transparently engineered of the two on paper. Superlux builds it around a 40 mm dynamic driver with a neodymium magnet, rates it at 102 dB SPL (1 mW) at 1 kHz, and quotes a frequency band of 10 Hz to 20,000 Hz with a 68Ω impedance at 1 kHz. Those are the numbers a studio buyer actually reads: the low-end extension reaches down to 10 Hz, the sensitivity is high enough that the headphone doesn't need a monster amp, and the 68Ω load sits in a middle ground — easy enough for most interfaces and desktop gear, but not as trivial to drive as a 32Ω consumer pair.
The design is closed-back and over-ear with plastic cups in black, and Superlux explicitly frames it around isolation: the airtight enclosed design is meant to let you work in noisy environments, and the description highlights a deep sound field with high resolution and balanced tone for recording and monitoring. In practice that's the classic tracking-room use case — you're cutting vocals or a guitar take, the click track is bleeding into your mic, and you want a sealed cup that keeps the mix in and the room out. The same logic applies to broadcast and live monitoring, where you're standing near a stage or in a booth and need to hear the feed, not the crowd.
The accessory list is the part that surprises people. You get a 3.3 ft (1 m) cable and a 9.8 ft (3 m) cable, a gold-plated 3.5 mm to 6.3 mm conversion plug, a cable clip and a carrying pouch. The short cable is the one you use at a desk or with a phone; the long one is what you use when you're tracking and need to walk across the room to the console. The clip keeps the cable from yanking on the cup. The pouch is basic but it means the headphone survives a gig bag.
OneOdio Monitor 60: Who It's For
The Monitor 60 is the more forward-looking package. OneOdio presents it as a professional studio headphone for audiophiles and DJs, and the sound description is the familiar three-part promise: clean highs, full mids, and deep, punchy lows — tuned so that mixing, mastering and casual listening all work from the same pair. That's a legitimate design goal for a monitor that has to double as a daily driver, and it's the kind of tuning DJs and bedroom producers tend to reach for, since a little low-end weight makes beatmatching and casual listening more enjoyable than a ruthlessly flat reference curve.
The real differentiator is in the bundle. The product is sold as the OneOdio Monitor 60 Headphones & USB-C to 3.5 mm Adapter, which tells you exactly what problem OneOdio is solving: the headphone terminates in a 3.5 mm connection, and the included USB-C adapter lets it work with phones, tablets and laptops that no longer have a headphone jack. If you've ever sat on a train with a pair of studio cans and a dongle you had to dig out of a bag, you know why that matters. Here the adapter is part of the kit, not an afterthought.
That makes the Monitor 60 a strong fit for the mobile creator: the person recording voiceovers on a phone, filming with a tablet, or DJing from a controller and a laptop that only offers USB-C. It's also the easier recommendation for a general listener who wants one headphone that moves between a desktop setup and a phone without a drawer full of adapters.
The honest caveat is the spec sheet. OneOdio publishes the positioning and the adapter, but not the impedance, sensitivity or frequency response figures. For a buyer who compares headphones by the numbers — and if you're cross-shopping against the HD661, you probably do — that's a real gap. You're trusting the tuning and the design intent rather than verifying a 10 Hz–20 kHz claim and a 68Ω load. It doesn't make the headphone worse; it just makes it harder to predict how it will behave with a given amp or interface before it arrives.
Side-by-Side: Which Should You Choose?
• Best for published, verifiable specs → Superlux HD661. 40 mm neodymium drivers, 102 dB sensitivity, 10 Hz–20 kHz, 68Ω. You can plan around those numbers.
• Best for USB-C devices out of the box → OneOdio Monitor 60. The USB-C to 3.5 mm adapter is included, so phones, tablets and modern laptops connect without extra purchases.
• Best for studio cable runs and amp connections → Superlux HD661. It ships with both a 3.3 ft and a 9.8 ft cable plus a gold-plated 3.5 mm to 6.3 mm adapter.
• Best for DJ and mixing-tuned listening → OneOdio Monitor 60. OneOdio explicitly tunes for clean highs, rich mids and punchy lows — a livelier curve than a flat reference monitor.
• Best for isolation in noisy rooms → Superlux HD661. The enclosed, airtight over-ear design is built around blocking external noise for tracking, live and broadcast work.
• Best for a minimal, one-cable lifestyle → OneOdio Monitor 60. Fewer accessories to manage, and the adapter covers the port you're most likely to have.
• Best for lower-impedance-friendly gear → uncertain. OneOdio doesn't publish impedance, so if your source is weak, the HD661's 68Ω figure is at least something you can reason about.
• Best for a kit that survives gigging → Superlux HD661. Cable clip and carrying pouch are included; the Monitor 60's listed bundle is the headphone and the adapter.
In my opinion, I'd buy the Superlux HD661 if I were setting up a desk for recording, monitoring or broadcast work. The published driver, sensitivity, impedance and frequency figures tell me what I'm getting, the enclosed design is aimed squarely at isolation, and the two cables plus the 6.3 mm adapter mean it slots into a real studio chain without a trip to the store. I'd pick the OneOdio Monitor 60 instead if my daily driver is a USB-C phone, tablet or laptop and I want a studio-styled headphone that connects without a dongle hunt — I'd just accept that I'm buying on design intent rather than on a full spec sheet.
FAQ
The HD661 lists a 68Ω impedance and 102 dB sensitivity, which most phones can handle, though a low-impedance pair would be easier. OneOdio doesn't publish impedance for the Monitor 60, so I can't compare the load directly — but the bundled USB-C adapter means it connects to a phone more conveniently.
For the HD661, yes if you're plugging into a USB-C phone — you'd supply your own. For the Monitor 60, no: the USB-C to 3.5 mm adapter is part of the package.
For tracking in a noisy room, I'd lean HD661 because the enclosed design targets isolation and the long cable reaches a console. For mixing and casual listening with a livelier low end, the Monitor 60's tuning is aimed at that. Check the current price on Amazon before deciding, since that often settles the tie.
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