SMSL M3 USB DAC Power Amplifier Review

When you are looking for a portable headphone amp, what is your most concern?

Price, performance, build or other thing?

Well, if you are not sure at first thought, It is fine.

Let’s take a look at an entry level portable DAC headphone amplifier, SMSL M3. Maybe you will have the answer after reading it.

Now, let’s go.

SMSL is  a company known to offer an extensive range of amplifiers and other audio products,  and it is very popular for the durable build of its product.

M3 is a USB-powered headphone amplifier from the brand. It can be used with many different types of devices to improve the sound quality. In this SMSL Audio M3 review, we’ll have a detailed look at the build, specifications, features, and pros and cons of this headphone amp DAC.

Design and Specification

Unlike most other amplifiers available in the market, SMSL M3 is designed in a much different way. It is more like a slab with small rubber feet which you can easily place on a flat surface.

If you have used a DVD player in the past, M3 is a smaller version of DVD player,  as far as the design of the amplifier is concerned. In order to enhance the durability, the shell of the device, the buttons, are all made from aluminum.

SMSL M3 has a  very compact size and it is  light in weight. It only weighs 7.2 ounces and measures 4 x 4.5 x 2.5 inches. So you can easily hold it in the palm of your hand and it can be easily carried in your pocket or backpack.

Smsl M3

On the front of the device, there is a single jack for headphones and volume control. On the left side is the function button and the LED indicator which light up based on the volume and input.

With the help of the function key, you can select the audio source. The short press will help you select the audio source, and long press turns the device on and off.

At the back, you have multiple output ports, like RCA analog right channel input, left channel input, coaxial input, and optical input, as well as, two USB ports for power input and USB input.

Features of SMSL M3

SMSL M3  features with an advanced purified power circuit and has a maximum power output of 1.5W. It can be easily powered by a mobile phone, tablet, or a computer.

However, it is not compatible with Apple iPhone and iPad which may a letdown for a lot of people.

The good thing, you  can  connect this device to a power bank to generate better sound.

It has a 24 bit asynchronous USB input and its 24 bit/192kHz advanced decoding chip is CS4398,  which is widely used in a number of high-end amplifiers.

The DAC is compatible with all the Hi-Fi headphones,  and the great thing is you can see  the full frequency sampling rate  from the front panel. It supports computer USB as well as OTG USB which makes it easier for the users to charge the device, no matter if they are at home or traveling.

One thing to remember is that the M3 is NOT COMPATIBLE WITH 16 BIT AUDIO -only 24 bit, which is fine, just set Windows and Foobar to output 24 bits.

Performance of SMSL M3

I tested SMSL M3 with quite a few high-end headphones and with a Windows computer as well as an Android smart-phone. Also, I tried many different types of music with the amplifier, like rock, blues, jazz, etc. to get a better feel of its performance.

As soon as I plugged in the headphone and played the song, it was very much evident that the amplifier has significantly improved the quality of the song.  The lows and mids were clearer and the bass was tighter.

However, with rock songs, I felt that the amplifier was a little loud. Even at the lowest volume, the sound was a little too much for me. But this can be a good choice for people who love listening loud music.

Keep in mind that, listening too loud music for a long time can damage the sensitive structures of the inner ear.

In case you are wondering the parameter of SMSL M3, 

Shell Aluminum alloy shell, solid aluminum buttons and knobs
DAC chipCS4398
Output power level1.9 Vrms
THD+N< 0.006%
Dynamic range> 112 dB
SNR> 107 dB
Channel separation> 105 dB
Sample rateUSB: 96 kHz (24 bit)
Optical and coaxial: 192 kHz (24 bit)
Output power108 mw: 32 ohm at THD 0.1%
85 mW: 64 ohm at THD 0.1%
49 mW: 150 ohm at THD 0.001%
24 mW: 300 ohm at THD 0.001%
InputsUSB, optical, coaxial
Outputs Line, headphone amp
DimensionsExcluding protrusions: 3.75 x 3 x 1.2 in (9.5 x 7.6 x 3 cm)
Weight7.5 oz (212 g)

Pros and Cons

While there is no denying the fact that M3 from SMSL is an excellent product at a highly affordable price tag, it has quite a few flaws too. Let us have a look at some of the pros and cons of this best portable DAC-


Solid build

Multiple input options

USB powered

Easy controls

Highly affordable

Compact and light in weight

Can be used with computer and smartphones


Not compatible with Apple iPhone and iPad

Audio was too loud in some instances

Some users have mentioned that the performance suffers when used along with high-end headphones


SMSL M3 USB Powered Audio Decoder is a value-for-money product.

This DAC/amp will help you improve the sound quality without taking up too much space in your bag or on your desk.

It has a solid build, multiple output options, and it is compatible with smartphones, tablets, and computers, and is very easy to use.

With its competitive price tag, we can say that it is one of the impressive DAC headphone amp in the market.