If you want robust dual-device charging and a bright display for long family road trips, choose Arestech FM Transmitter; if you need pristine audio fidelity with zero static noise and seamless auto-connect features, choose Aston Innovations SoundTek A1+.
• Arestech FM Transmitter: Its biggest strength is the integrated QC 3.0 fast-charging hub that powers two devices simultaneously, but its trade-off is reliance on FM radio frequencies which can sometimes introduce background hiss depending on your local signal. This pick is for drivers who prioritize keeping phones charged and want visual feedback in low light.
• Aston Innovations SoundTek A1+: It shines with advanced audio codecs like AAC and aptX-HD that deliver studio-quality sound through an AUX connection, yet it lacks built-in charging ports, requiring a separate cable solution. This pick is for audiophiles and tech-savvy drivers who demand crystal-clear calls and music without any radio interference.
The Arestech FM Transmitter is designed for the practical driver who needs more than just music playback in their vehicle. At its core, this device solves the common problem of running out of battery power during extended drives. By integrating a Quick Charge 3.0 port alongside a standard 2.4A output, it allows you to charge two different devices at once while they are connected to the car's electrical system. This capability is particularly valuable when traveling with family, where multiple passengers might be relying on their smartphones for navigation, entertainment, or communication. The ability to charge two devices simultaneously means you aren't fighting over a single outlet, a common friction point on long journeys.
Beyond power management, the Arestech unit addresses visibility and connectivity issues. It features a seven-color LED backlight, ensuring that the interface remains clearly visible even in dark driving environments or at night. This isn't just a cosmetic feature; it provides functional utility when adjusting settings without straining your eyes or taking your focus off the road. The Bluetooth 5.0 technology ensures a stable link to your smartphone, supporting high-definition audio streaming and hands-free calling. The inclusion of CVC noise reduction in the microphone is a significant detail for safety, as it helps filter out engine noise and wind, making conversations clearer for both parties.
However, this product is not a universal solution for every car interior. Because it transmits audio via FM signals, its performance is inherently tied to the quality of the radio frequency landscape in your specific area. While the device uses anti-interference technology to maintain a strong signal, some locations might still experience occasional static or overlap with other stations. Additionally, the unit is slightly larger than pure audio adapters, measuring 0.86 x 2.5 x 2.5 inches, which might be noticeable on smaller dashboard mounts. If your primary goal is purely listening to music and you have a dedicated charger already, the extra bulk and the reliance on FM transmission might feel like unnecessary complexity. But for those who need a central hub for charging and clear voice calls, it stands out as a capable all-in-one tool.
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-11-07 · 7 min read · Independent comparison
The Aston Innovations SoundTek A1+ targets a different demographic: the driver who treats their car audio system as an extension of their home hi-fi setup. Unlike the FM transmitter approach, this device connects directly to your car's AUX input, bypassing the radio spectrum entirely. The inclusion of Qualcomm chipset support for AAC and aptX-HD codecs means the audio signal is processed with higher fidelity, preserving the nuances of the original recording that lower-quality compression often strips away.
Convenience is also a major selling point for the SoundTek A1+. It features an auto-on and auto-connect function that syncs with your phone the moment you start the car, removing the manual step of searching for Bluetooth connections. Furthermore, its multipoint technology allows it to connect to two phones simultaneously. This is a game-changer for shared vehicles or households where multiple people drive the same car. You can switch between a personal phone and a partner's phone instantly without disconnecting one to pair the other. The device is incredibly compact, measuring just 0.43 x 1.69 x 1.69 inches, making it nearly invisible once plugged into the AUX jack. It sits unobtrusively, blending into the car's interior design without drawing attention.
Despite these advantages, the SoundTek A1+ has limitations regarding versatility. It does not include any charging ports, meaning you must rely on your car's existing cigarette lighter or USB ports for power, which might require managing extra cables. The lack of an FM transmitter function also means it cannot play music through speakers that do not have an AUX input, restricting its use to cars with older stereo systems or those equipped with modern auxiliary jacks. If your vehicle lacks an AUX port, this device is incompatible unless you purchase a separate FM adapter. It is strictly an audio enhancement tool rather than a multi-function power station. Therefore, it is best suited for users who already have reliable charging solutions and prioritize superior sound quality and seamless connectivity above all else.
• Best for simultaneous charging → Arestech FM Transmitter: With its dual outputs including QC 3.0, it keeps multiple devices powered up effortlessly, a critical feature for family road trips.
• Best for audio clarity and no static → Aston Innovations SoundTek A1+: The direct AUX connection and high-end codecs ensure pure sound without the risk of FM interference or background noise.
• Best for ease of use → Aston Innovations SoundTek A1+: Auto-power-on and multipoint Bluetooth connection remove the need for manual pairing every time you enter the car.
• Best for visibility in dark conditions → Arestech FM Transmitter: The seven-color LED backlight makes controls easy to find and adjust at night without distraction.
• Best for call quality in noisy environments → Arestech FM Transmitter: The built-in CVC noise reduction microphone specifically targets engine and wind noise for clearer conversations.
• Best for compactness → Aston Innovations SoundTek A1+: At under half an inch thick, it is significantly smaller and less obtrusive than the FM transmitter.
• Best for families with multiple drivers → Aston Innovations SoundTek A1+: Connecting to two phones at once allows for instant switching between drivers' devices.
• Best for older car stereos without AUX → Arestech FM Transmitter: Since it broadcasts via FM radio, it works with any car speaker system that has a tuner, regardless of age.
After weighing the specifications and real-world application of both devices, I would buy the Arestech FM Transmitter for my own family road trips. The combination of fast charging for multiple devices and the ability to see the controls in the dark outweighs the slight risk of FM interference. Family travel involves a lot of electronics, and having a reliable way to keep phones charged while navigating is essential. However, if your priority is purely the quality of the music and you have a reliable external charger, the Aston Innovations SoundTek A1+ offers a superior sonic experience that feels closer to a home stereo system. In my opinion, the Arestech model provides the most balanced utility for the average driver who needs everything in one place.
Yes, the Arestech unit is compatible with all cars and trucks operating on 12 to 24 volts, provided the vehicle has an FM radio tuner to receive the signal.
Absolutely. The multipoint technology allows the device to maintain active connections with two phones simultaneously, enabling seamless switching between them.
While the Arestech uses CVC noise reduction to minimize background noise, some static may occur depending on your local radio signal strength, whereas the SoundTek A1+ guarantees zero static via its direct AUX connection.
Yes, because the SoundTek A1+ does not include any built-in charging ports, you will need to use your car's existing power outlets to charge your mobile devices.
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.