The Lotoo PAW S1 USB hifi-dongle is a new audiophile portable DAC. It has a very efficient circuitry that creates a clean, powerful and energy-saving headphone amplification for smartphones, tablets, laptops, video consoles and many other devices with a USB connection. It also supports Apple devices with a Lightning connection through a cable that is sold separately. The popular 4.4mm Pentaconn balanced output is also supported.
A neat feature is the use of pre-configured sound filters that implement a parametric equalizer (PMEQ) with what Lotoo calls Acoustic Timbre Embellisher (ATE). When asking Lotoo, I received the reply that they implement an “array of studio effects”. I am not sure where I have to search to find out what they do exactly. I cannot notice any change in the impulse response, phase or distortion other than what is clearly due to the equalizer. However, some of these presets utilize crossfeed to a quite noticeable extent.
List of Presets
+ uses crossfeed or another way of 3D stereo enhancement
++ has a strong surround enhancement
- Movie +
- Game ++
- Radio +
- Near Field +
- Far Field ++
- Full Bass
My Favorite Presets
Near Field and Free Field (and Brighter)
Many IEM are tuned to sound full, rich and warm. These two presets subtly correct a majority of the IEM to a more neutral signature. Don’t expect your headphones to suddenly sound studio-neutral, but I think even adjusting by 2 dB, like in this case, creates a noticeable improvement. Comparing to my RME ADI-2 DAC FS or Chord Hugo 2, the PAW S1 has a rather warm signature as well, so lifting the top end is to my preference. Near Field lifts mids and treble, while Far Field is more subtle in the midrange.
I noticed that these two filters also use crossfeed. Far Field has a stronger effect than Near Field. BTW, I am a huge fan of crossfeed. If you don’t like enhanced stereo width, the Brighter setting will work too.
The Sweet preset creates a small boost in the bass and treble of around 3 dB. But it also enhances the soundstage significantly. It works well at lower volume for a livelier presentation. I found it to be a great filter to pair with mid-centric headphones like the Sennheiser HD 660 S.
Dental softens the midrange and creates a more intimate experience. I am really confused by the name, because the only audio reference I can think of is “bite” – a term I would use to describe a forward and aggressive upper midrange. But the filters here are doing the opposite. So maybe if you don’t like the thought of ice cream touching your teeth, then this could be the filter array for you.
Movie and Game
I do not recommend either for music. But many of us use the PAW S1 with a smartphone and tablet, with which we also consume video. I found that the Movie preset works very well for the name it carries. The midrange is boosted to better hear voices, but not in a way that boosts overtones. Instead, it works well to cover for the lack of a center speaker. The surround experience is also enhanced.
The Game preset is even a bit more aggressive and has a rather weird correction which focusses on clarity. I can imagine this is a mean to better pick up directional and location information for competitive shooters. I am more of a casual gamer and for me this preset is not enhancing the experience with the Indie games I play on the Nintendo Switch. This might be different for you, though.
Yep, I guess I have to include this option. Often the audio sounds best when it is manipulated as little as possible. The PAW S1 provides clean amplification and enough power to suit all my IEM and headphones. (I don’t have any very power-hungry unportable headphones.) The signature of the S1 is a little bit on the warm side. It can’t quite match the organic texture and treble smoothness of the Chord Mojo, but it still pairs reasonable well with IEM that appreciate some warmth. E.g. the Campfire Solaris, DUNU Luna, final A8000 and InEar ProPhile 8.
Presets I Disagree With
I really would not mind the option to delete any of the presets. In case Lotoo is reading, when selecting a preset, can you include the option to remove a preset when holding the minus button? Less clutter is always great. Thanks!
The preset Classic rolls off in the treble by what seems to be a shelf correction. I don’t quite get why -6 dB at 10kHz+ is supposed to help with any recording. For one, I think Classic refers to Oldies and not to Classical music. But then again, I would have called it YouTube or Amateur, because the cut in treble information isn’t enhancing any of my albums anyway.
This just does not work for me at all. This filter array sounds extremely dull. I am sure one could have thought of a better way to enhance the bass experience without completely castrating the treble. Here is a suggestion.
Jazz and Rock
The coloration is strong with these two filter sets. Jazz and Rock include such a broad selection of music styles, that my preference for each of the genres just doesn’t seem to vibe well with what the designer was thinking of when creating these presets. Jazz completely destroys the timbre and Rock throws compression artifacts right into your face. Both seem to be very unique and niche corrections which make it very difficult to recommend unless you have a very specific recording and a special headphone that for some reason need this kind of correction.
I can think of some options that I would prefer over what is already included. Actually, I wouldn’t need any of the presets if I only had the following options.
Crossfeed: Narrow and Wide
I would really love to have the option to use nothing but crossfeed. Unfortunately, this is not possible. So I have to choose one of the following presets.
Narrow: Movie, Radio, Near Field
Wide: Game, Far Field
By default I choose Near Field but with those IEM, that already have a decent amount of treble, like some of my favorites (final A8000 and InEar ProPhile 8), this is a bit too hot. I would also prefer if the implementation of crossfeed would be more subtle overall. The bass smears more than with the low crossfeed settings of the ADI-2 DAC or Hugo 2.
Many of the filters increase the bass quantity, yes. But there is none that only enhances the very low frequencies. I am asking for something more in line with Harman. This could be implemented with a crossfeed that only affects the lows, too, for a 3D effect that does not reduce clarity in the midrange and treble.
Keep in mind that the presets do more than just implement an equalizer. So I cannot show you the full truth. But here is how the tonality is changed when using any of the filters. Enjoy!