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If you want a single pair of everyday Bluetooth over-ear headphones with aptX Low Latency, 50mm drivers, multipoint pairing and a wired fallback for music, movies and gaming, choose August EP650; if you need a two-headset TV listening system with independent volume, a charging dock and a 164ft range for a household watching together, choose SIMOLIO 737D.
• August EP650 biggest strength: 50mm dynamic drivers, aptX Low Latency for tight audio/video sync, multipoint pairing to two devices at once, and an EQ app for tuning the sound.
• August EP650 biggest trade-off: 15-hour battery life and a 10-metre Bluetooth range — plenty for personal listening, but modest next to a dedicated TV system.
• SIMOLIO 737D biggest strength: two pre-paired over-ear headsets with independent volume control, a transmitter that doubles as a charging dock, and up to 164ft of transmitting range.
• SIMOLIO 737D biggest trade-off: it's built around TV watching — the spec sheet lists no noise control, and it ships as a two-headset kit rather than a single portable pair.
• Best for one listener on the move → August EP650.
• Best for couples, families or hard-of-hearing TV viewers sharing one screen → SIMOLIO 737D.
The August EP650 is a personal listening headphone first. Its 50mm dynamic drivers are the headline: that's a large driver for an over-ear, and August pairs it with a 60Hz–20kHz frequency range and a low-impedance 50-ohm design. The brand's own framing leans on deep bass and detailed mids — in my opinion that's a sensible target for someone who wants a bit of weight under pop, hip-hop or action soundtracks rather than a flat, clinical monitor sound. The free August Audio EQ app for Android and iOS lets you push the tuning further, which is unusual at this price-agnostic tier of feature set and genuinely useful if the stock curve isn't to your taste.
The second thing that defines it is aptX Low Latency over Bluetooth 5.1. Low Latency matters most when you're watching video or gaming, because it shrinks the gap between the picture and the sound. August also lists multipoint, so the EP650 can hold two source devices at once — your laptop and your phone, say — and pause one to take a call on the other. There's an integrated microphone and an on-ear remote for volume, track skipping and calls, and the headset is listed as compatible with VoIP services like Skype and with PC gaming. A 3.5mm jack gives you a wired option when you'd rather not run the battery down, and the enclosure mixes ABS, metal, PU and sponge with a Li-ion battery — a normal, durable-feeling construction for this class.
Who should buy it? Someone who wants one pair of over-ear headphones to move between music, films, calls and games, and who values being able to connect to two devices without re-pairing. The adjustable headband, flexible earcups and soft padding are aimed squarely at long sessions — travel, work, relaxation.
SIMOLIO 737D: Who It's For
The SIMOLIO 737D Plus is a different animal entirely: it's a TV listening system sold as a kit, and it's honest about that. You get two pre-paired over-ear headsets, a transmitter that doubles as a charging dock, a power adapter, an audio cable kit, a Type-C charging cable and printed guides. Bluetooth 5.3 handles the wireless side, with a listed audio latency of 25 milliseconds — that's the number that explains why the brand can claim in-sync audio and video without you noticing a lip-sync drift.
The two features that justify the whole package are independent volume control and the bypass function. Each headset has its own volume dial, so one viewer can run loud while the other stays comfortable. Bypass lets the headsets share the same audio output as your existing soundbar or AV receiver, so the TV speakers (or soundbar) keep playing for everyone else while the headset wearer gets a private, individually levelled feed. That's the scenario this product exists for: couples and families with different hearing preferences, and seniors who need more gain than a TV's built-in speakers will give.
It's also flexible about sources. The transmitter plugs into a TV's OPT, AUX or RCA output and works with smart and non-smart TVs, and the range is listed at up to 164 feet in open air — enough to wander to the kitchen, garden or garage without dropping the feed. In Bluetooth mode, each headset can pair independently to a phone or tablet, which turns them into ordinary Bluetooth headphones when the TV is off. Comfort is handled with protein earmuffs and a retractable, soft-padded headband, and a full charge is listed at up to 20 hours. Two practical notes from the sheet: there's no L/R balance control on this model (SIMOLIO points to a different model for that), and on an optical connection you may need to set your TV or streaming app to PCM stereo rather than Dolby or 5.1 to get sound.
Who should buy it? Households where one or two people want their own volume on the same TV, or where someone needs a clearer, louder dialogue feed. The three EQ modes — clear dialogue, standard and cinema — are aimed exactly at that.
Who should skip it? A solo listener who just wants portable headphones for commuting and music. You'd be paying for a second headset, a dock and a transmitter you don't need. And if you want active noise cancellation, look elsewhere — the sheet lists noise control as "None."
• Best for aptX Low Latency and video/game sync on one device → August EP650.
• Best for zero-fuss TV sync with a dedicated transmitter → SIMOLIO 737D (Bluetooth 5.3, 25ms listed latency).
• Best for two people watching the same TV → SIMOLIO 737D, thanks to two pre-paired headsets and independent volume.
• Best for keeping your soundbar in the loop → SIMOLIO 737D, via the bypass feature.
• Best for battery life → SIMOLIO 737D at up to 20 hours versus the EP650's 15 hours.
• Best for wireless range → SIMOLIO 737D, listed at up to 164ft versus the EP650's 10 metres.
• Best for multipoint pairing and taking calls → August EP650, with two simultaneous source devices and an integrated mic.
• Best for sound tweaking on a single pair → August EP650, via the August Audio EQ app; for TV-specific tuning, the 737D's three EQ modes cover dialogue, standard and cinema.
• Best for a wired fallback → August EP650, which has a 3.5mm jack; the 737D is wireless-only.
In my opinion these two barely compete — they win in different rooms. If I wanted one pair of over-ear headphones for music, films, calls and gaming, with aptX Low Latency, multipoint and an EQ app to shape the sound, I'd buy the August EP650. If the real problem in my house were two people who can't agree on TV volume, or a family member who needs louder, clearer dialogue, I'd buy the SIMOLIO 737D without hesitation — the dual headsets, independent volume, bypass and charging dock are built precisely for that. Decide which problem you actually have, then check the current price on Amazon before committing.
what is aptx adaptive headphones
aptX is a family of Bluetooth audio codecs, and aptX Adaptive is a variant designed to balance audio quality and latency depending on what you're doing. Neither product on this page lists aptX Adaptive in its specs: the August EP650 lists aptX Low Latency, and the SIMOLIO 737D lists Bluetooth 5.3 with a 25ms audio latency figure instead. If aptX Adaptive specifically is a must-have, check the spec sheet of whatever you're considering rather than assuming it from the brand name.
Yes, but differently. The SIMOLIO 737D is purpose-built for it — its transmitter plugs into a TV's OPT, AUX or RCA output and supports two headsets at once. The August EP650 pairs to a Bluetooth-capable TV or source and relies on aptX Low Latency to keep audio and video in sync; August specifically notes that aptX Low Latency provides the tightest sync when used with compatible devices.
The SIMOLIO 737D ships with two pre-paired headsets, each with its own volume control, so two people can watch together at different levels. The August EP650 is a single headset; its multipoint feature connects to two source devices, not two listeners, so it's a one-person-at-a-time product.
The SIMOLIO 737D is the more natural fit for shared TV viewing, since each headset has independent volume and the bypass function lets the rest of the room keep using the soundbar. The August EP650 has sound isolation rather than active noise cancellation, so it reduces leakage passively rather than electronically. If quiet-for-others is your priority, the 737D's private, individually levelled feed is the more direct answer.
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