A Paw in your Palm!

PROS: neutral sound sig with a natural tonality, play/pause/skip hardware control, volume control, multi-platform compatibility, 3.5mm and 4.4mm outputs, MQA 4x support, ATE/EQ presets, Line Out, belt-clip.

CONS: higher price than S1, lightning cable is optional.

The product was provided to me free of charge for the review purpose in exchange for my honest opinion.

Manufacturer website: Lotoo. Available for sale from various retailers, including Musicteck.

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Intro.

In the past I used to cover more usb dac/amp dongles, but as I mentioned in one of my previous reviews, the demand for these thumb-size gadgets went through a roller-coaster ride. In the days of older smartphones with poor sound quality, they were a blessing. Then, sound quality of Android phones and iPhones improved, so demand went down. After disappearance of 3.5mm jack, it peaked up again and dropped down later with popularity of TWS. Then, last year Lotoo announced S1 and raised the bar by introducing a new device in PAW (Portable Audio Workstation) series with more advanced features, atypical for a regular thumb-size wired dongle.

Among those new features, Lotoo included volume control, less common in this type of devices, and both 3.5mm and 4.4mm headphone outputs, also less common since Pentaconn socket takes more room. And they added a display with access to EQ/DSP presets (non-editable) and other settings. There was also a dedicated opamp to boost output power, though the current draw from the source stayed relatively low. I covered S1 in many discussions on Head-fi and featured it in a number of my reviews as part of Digital Out pair up with various DAPs, though never got to finalize and to publish the official review while still waiting for the MQA certification of S1.

But as they say, if you wait long enough, the problem will either resolve itself or no longer be relevant. There is no problem with S1 and it is still relevant (LO feature was just added with new fw update). But turned out that I waited long enough for Lotoo to release S2 version of their popular dongle. So, is this a worthy follow up and would I recommend it as a must-have upgrade to S1? Let’s find out more in this review of Lotoo S2 usb dac/amp dongle.

Unboxing and Accessories.

S2 arrived in a compact black cardboard box inside of a white sleeve with a glossy 3D-like picture of S2 on its cover and list of basic features on the back. But despite its small size, the packaging box packs a lot of goodies. Once you remove the cover, you’ll find the star of the show, S2 sitting securely in a foam cutout, side by side with a belt clip accessory. Underneath, once you remove S2, you will find a small box with cables and adapter, and below it a warranty card and a very detailed manual. I usually don’t spend too much time on manuals, but found a few interesting details about MQA in this one. And if you ever misplace it, you can download it directly from Lotoo S2 support page where you can also find the latest fw.

The original S1 accessories were simplified down to usb-c to usb-c OTG short cable and usb-c to usb-A adapter. With S2, the only thing carried over was usb-c to usb-A adapter so you can use S2 as USB DAC with your laptop, while the rest was updated. First of all, the cable itself was revised, using multi-core pure OFC copper wires and updated connector housing with improved strain relief and tighter fitting connector. The jacket of the cable is also higher quality, using more durable PVC instead of a braided fabric sleeve which is prone to faster wear’n’tear. In addition to a short 2.5” cable (excluding connector length), Lotoo also included a bonus long cable, exactly the same build quality with updated design and almost 32” in length. Longer cable is more convenient when attaching S2 to your computer, but there is another idea behind the extended cable version.

Short cable will allow you to keep S2 right next to your phone for convenience to carry both in your pocket. But with access to playback controls, Lotoo decided to come up with a new way of carrying S2. In addition to longer cable, Lotoo also designed and included a belt-clip with a built-in cable winder/organizer. This way you can have S2 clipped to your pocket, belt, or even a backpack or a bag strap, and use a longer cable to connect to the phone in your pocket. This way phone will stay in your pocket and you have easy access to S2 controls to change the volume and to skip or pause the playback. The only thing you do have to remember, this is a directional cable, and UFP (upstream facing port) labeled connector with U> will have to be connected to S2.

For those with iPhone who require usb-c to lightning cable, Lotoo also made one with the same updated wires and connectors, but it is optional and you have to buy it separately. Also, for those who are familiar with their original usb-c to lightning cable, it wasn’t able to provide 5V to the dongle, only 3.85V. Per my measurements, the new updated lighting OTG cable provides a solid 5V output.

Page 2 – Design and under the hood.
Page 3 – Sound analysis and Pair up.
Page 4 – Comparison and Conclusion.