SMSL DO300EX HiFi DAC Headphone Amplifier, AK4499EX AK4191 Chip XU316 USB DAC, DSD512 PCM32Bit/768kHz Digital Audio Converter with 4.4mm/6.35mm Headphone Output (Black)

Using this in my main stereo system being fed by a Wiim Pro plus (coaxial connection) and cd transport (optical connection). The DAC is connected via balanced xlr into a Quad pre-amplifier. The Quad has an option to bypass the tone shaping circuits for the balanced connections, which is what i selected. The Quad pre then connects to a pair of Neumann studio monitors and sub. Initially I left all the default settings on the SMSL DO300EX unchanged as I wanted to check whether the reviews of it sounding neutral were 'true'. Well it did sound flat, as I expected. The Neumanns do not add anything that isn't in the signal already so what I was hearing was the recording of the music and nothing else. There is a noticeable gain drop when using this DAC compared to using the Wiim plugged direct into the Quad. The Wiim has an AKM chipset also (AK4493SEQ) so I'm not sure if this behaviour is related to the pcm filters always being 'on'. With ESS based DACS there is usually an option to turn off the filters. That might be important to you or not, so you might want to choose your chipset carefully. I messed about with the volume pot on the SMSL and settled on -3dB in the end. You are able to 'lock' the volume pot at your chosen level in the comprehensive menu to prevent unwanted changes. Next I altered the sound colour setting and noticed very subtle changes between each setting. Like really subtle! I reverted back to the default filter '1) sharp roll-off'. The included manual provides basic information only. There is no illustration or description of how the sound profiles or pcm filters alter the sound spectrum. You will have to go online to find the graphical plots of the filters for the chipset installed in this device.Listening to a variety of music sources it is obvious that the level of detail is excellent and comparable to the Wiim Pro Plus direct as you would expect. Forget terms like "warm" or "less digital" sounding, this is a DAC. Phrases by AKM of "sound as if you were there" are marketing mumbo jumbo! Everything else in the chain has to be up to scratch too for this to be a close reality. What I did find was that listening to this DAC for several hours straight was more pleasurable than when listening through the Wiim Pro Plus direct. Even with the Wiim's EQ abilities. This DAC does a job and it does it very well. No glitches, no hair on the sound, just a conversion with all the detail present. The headphone stage is an added feature which might sway your final decision.

I upgraded from a FOSI Q4 to this, which costs ~£70 and features 1 Cirrus chip. Cirrus chips are mainly used in portable devices now, or in unison of quantites of 6-12 in some modern desktop DACS.The SMSL DO300EX is 4 times the price, 4 times the size, but does it sound 4 times as good?I'm listening with Fostex TH900 and also Sennheiser Momentum (1st gen). Using the unbalanced output as it's such a short distance it won't matter. After fiddling with the settings, I'm set on the default sharp roll off, low gain, as both headphones are low impedance, and a narrow DSD. The sound is plenty loud even on low gain, below 0.0db, for these easy to drive headphones at 25-32 ohms.The display can be permanently on, altered brightness, or dim after 5s - 1min, which is nice.I did have an issues with the DAC disconnecting, so it's important to have the DAC directly USB into the PC, instead of using a USB extender in the middle. This fixed the issue completely.I immediately noticed that the sound was much more crisp & detailed and the bass was a lot more punchy and deep. The sound generally overall feels a lot more premium, responsive and present.I don't have anything in the general price point to compare to, but I would say it's a very neutral DAC and it allows my V shaped headphones to colour the sound very nicely. The other review saying that it smooths out the voices, not really sure what that person is on about there, I don't hear that at all.My goal was to buy a personal endgame upgrade, as IMO the diminshing returns for cost with DACS likely goes exponential beyond £300-500 range. Overall, does it sound better than a cheaper alternative with a single AKM or ESS chip with less features? I couldn't tell you, as I have no reference to similar products. If you are more budget constrained, perhaps it would be a better alternative. But as it stands, i'm very happy with the purchase and would be satisfied to never upgrade again. I am a little worried about the unit eventually breaking, but if it lasts several years before a capacitor blows, and can be repaired, then that seems ok.

Full disclosure: I design and build DACs for a hobby, so spend a lot of time thinking about them and listening for differences between them. This is a good one! From a technical perspective, it's an odball because the AKM chip here is a hybrid between delta-sigma (1-bit, i.e., almost all modern DACs since the early '90s) and multi-bit switching resistor-based... which is sort of an old and primitive tech.Anyway, that primitive tech (resistor switching, like R2R) tends to sound more like cheap vinyl than cheap CD. But at its best, it can sound like the best of both worlds in terms of well-implemented vinyl and similarly well-implemented CD. To me, this DAC sounds more towards the latter: it has the slam and detail of good digital with the presence and body of good analogue. I can only assume that this combination of subjective qualities maps onto the tech.While I still prefer the old-school 'true' multibit DAC implementations, especially with the TDA1541A, the commercially available options either lack a remote control, lack sufficient variety of digital inputs, etc, and functionality holds some sway. More importantly, the emotional engagement afforded by this unit is as good as anything I've heard aside from the unobtainable designs. Detail is not the battlefield of modern DAC (device) design. But engagement arguably is and this device is surprisingly good at that.