Sennheiser’s BTD 700 arrives as a sleek, no-nonsense Bluetooth dongle designed to fix a problem everyone with wireless headphones already knows: your device’s built-in Bluetooth is usually garbage. At just 2.2 grams and 24mm long, it’s smaller than most flash drives but packs serious firepower—aptX codecs, Auracast, and low-latency gaming modes all wrapped in one plug-and-play USB-C package.
Throw in the USB-A adapter, and suddenly your aging laptop or desktop isn’t holding back your headphones anymore. It’s the sort of elegant, minimalist fix Deiter Rams might reluctantly approve—because sometimes good design means fixing the basics first.
High-Def Bluetooth That Doesn’t Make Your Ears Cry
The Sennheiser BTD 700 isn’t here to kiss your Bluetooth woes goodbye—it’s here to stomp on them with aptX Lossless and aptX Adaptive codecs, delivering wireless audio up to a lush 24-bit/96 kHz. That means your earbuds, headphones, or speakers suddenly go from tin-can-and-string quality to something closer to what the artist actually intended. Got a pair of Sennheiser MOMENTUM 4 or ACCENTUM headphones? Good. They’re already prepped to milk this high-def goodness.

Plug, Play, and Pretend Your Laptop Knows What It’s Doing
This dongle is class-compliant, meaning it sidesteps your device’s sorry excuse for Bluetooth like a pro, no complicated setup required—just shove it in like a flash drive and go. Android, iOS, Windows, MacOS? Doesn’t matter. Thanks to Bluetooth 5.4, your options suddenly multiply. Fire up an Auracast broadcast for that outdoor movie night, stream your favorite album in studio quality, or take a day’s worth of calls on the comfy Sennheiser MOMENTUM 4 headphones without sounding like a robot on a tin can.
Why It Matters: Key Features
- Audiophile-Grade Codecs: aptX Adaptive and aptX Lossless crank your wireless sound up to 24-bit/96 kHz. Translation? No more excuses for “Bluetooth” sounding like a tinny mess.
- Game Mode: A latency low enough (30 milliseconds) to keep your audio locked tight with the action—because watching a game where the sound arrives late is so last decade.
- Auracast™ Support: Share your tunes (or lectures, if you must) with multiple Auracast-enabled devices at once. Party trick approved.
- Crystal-Clear Calls: Finally, Bluetooth that actually makes you sound like a human on conference calls—no more “Can you hear me now?” moments.

How Does the Sennheiser BTD 700 Work with iPhones That Don’t Support aptX?
The BTD 700 acts as an external Bluetooth transmitter that handles the audio codecs itself—so even if your iPhone can’t natively do aptX (which is true for all iPhones, since Apple only supports AAC and SBC), the dongle will still send aptX Adaptive or aptX Lossless to your compatible headphones.
In other words: your iPhone sees the dongle as a USB DAC and sends standard audio to the dongle, which then encodes and transmits the audio to your headphones using the high-quality aptX codecs the iPhone alone can’t manage. This bypasses the iPhone’s codec limitations and upgrades your wireless sound quality without any fiddling.
So if you pair the BTD 700 with aptX-enabled headphones like the Sennheiser MOMENTUM series, you get all the benefits of aptX audio even on an iPhone that normally wouldn’t support it. It’s like giving your phone a secret audiophile upgrade card.
You can turn off your phone or tablet’s built-in Bluetooth and still use the Sennheiser BTD 700, since it operates independently of the device’s OS. You can also keep your AirPods connected via the native Bluetooth while your MOMENTUM 4 headphones pair with the dongle—letting you run two wireless audio connections at once without a fuss.
Comparison
BTD 600 | BTD 700 | |
MSRP | $39.95 | $59.95 |
Release Date | June 2022 | June 2025 |
SKU | 700248 | 700434 |
Connectivity | Bluetooth 5.2 compliant, class 1, 10 mW (max) | Bluetooth 5.4 compliant, class 1, 10 mW (max) |
Transmission frequency | 2,402 MHz to 2,480 MHz; GFSK, π/4 DQPSK / 8DPSK | 2,402 MHz to 2,480 MHz; GFSK, π/4 DQPSK / 8DPSK |
Supported Profiles | HTP, A2DP, AVRCP | HFP, A2DP, Auracast™ |
Supported codecs | SBC, aptX™, aptX™ Adaptive | SBC, aptX™, aptX™ Adaptive aptX™ Lossless, LC3 |
Dongle / Adapter Weight | 1.9g / 2.8g | 2.2 g / 3 g |
Dongle Size | 15.5 x 19.7 x 7.8 mm | 23.8 x 15.2 x 7.6 mm |
Adapter Size | 15.5 x 25.3 x 7.8 mm | 25.69 x 15.2 x 7.6 mm |
Supported operating systems | Windows 8.1 or later MacOS version 11 or later | Windows 10 or higher, Mac OS V11 and V12, Android 13 or higher, iPhone or iPad with USB-C |
Storage Temperature | Temp: –25 to +70°C, Rel. humidity 10 to 90% | Temp: –25 to +70°C, Rel. humidity 10 to 90% |
App support | Sennheiser Transmitter Updater (PC/Mac) | Sennheiser Transmitter Updater / (PC/Mac) |

The Bottom Line
The Sennheiser BTD 700 is tiny, unassuming, and far smarter than the Bluetooth nonsense built into most devices—like a brilliant butler in a sea of bumbling fools. At 2.2 grams, it slips in unnoticed but immediately upgrades your audio to something your ears might actually enjoy. Plug-and-play means no brain cells wasted, and with premium codecs, low latency, and Auracast, it’s the only dongle that won’t make you question humanity. For under sixty bucks, it’s the kind of no-nonsense, elegant fix that makes you wonder why your laptop’s Bluetooth hasn’t been fired yet.
Price & Availability
The BTD 700 lands on June 3rd, 2025, priced at $59.95 USD / $69.95 CAD at sennheiser-hearing.com, and from select Sennheiser retailers. Your headphones will thank you—assuming they could talk, of course.
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Anton
June 3, 2025 at 8:02 pm
It’s interesting to me that Apple still refuses to play ball with everyone else in regard to Bluetooth codecs. Probably explains why I’ve never considered AirPods.
Ian White
June 3, 2025 at 8:10 pm
Anton,
Apple will continue to do what it does until it’s not financially smart. Should Apple ever decide to end support for AAC, we will all dance if they take on aptX and its variants.
Don’t hold your breath.
IW