Note: This article is based upon the video "Battle Royale: DX5 vs M500 vs EF400 vs DX7 Pro+ vs K9 Pro ESS” made by Passion For Sound on their YouTube channel and is printed here in partnership with Passion For Sound. The review was originally posted on September 13th, 2022. Edits have been made for clarity and length.
Let the battle begin! Lachlan of Passion for Sound pitted the best <$1,000 all-in-one units against each other in a roundup review on his YouTube channel. He compared the TOPPING DX5, SMSL M500 MkIII, HIFIMAN EF400, TOPPING DX7 Pro+, and the FiiO K9 PRO ESS.
Watch the full review below or scroll on for an abridged transcript.
Due to the lengthy runtime of the video review, we’ve only transcribed the introduction, preliminary conclusion, and final conclusion chapters. Our transcription doesn’t do Lachlan’s incisive and nuanced commentary justice, and we encourage everyone to watch the full video.
Hi, folks. Welcome to another Passion for Sound audio review. Today, we have a battle between five different all-in-ones. What I mean by that is that all of these are a DAC and headphone amp (and also a preamp in most cases). They’re all of that wrapped into a single box. I happen to have been sent a few of these for review all in short order, and so I thought rather than do individual reviews, where inevitably I would have compared them against each other anyway, I thought let’s just start off by comparing all of the all-in-ones that I have handy up to $1000.
I had some really interesting conclusions, and I’m not done yet but let me give you a quick summary of how these perform just as all-in-one’s driving headphones. I’m going to come back around in a moment and talk about them with IEMs and also as DACs or preamps only. But first let’s summarize them as all-in-one units only.
The SMSL M500 MkIII is the clear standout when combining price, sound quality, and the feature set. The M500 MkIII is an absolute beast.
The DX7 Pro+ comes in a very, very close second. It’s not quite as good as the M500 MkIII from a sonic perspective, but it’s got more power, it’s got I2S, it’s got balance control, and some of you are going to prefer the design.
The K9 Pro ESS has been bumped to third place for me, because it’s got slightly more features than the other two, but the sound quality from the M500 MkIII and DX7 Pro+ is clearly better.
The EF400 kind of sits on its own. For me, it’s got the best sound of all of them, but there is such a massive gulf in the feature set, and it also doesn’t seem to play well with high impedance headphones, so it’s got kind of a niche position. It’s number one in sound quality with lower impedance headphones, but it drops back so quickly, in terms of features and high impedance cans, that I really don’t know where to put it. I will put it as number one for sound quality for low impedance cans, but for everything else I’m probably going to go for the M500 as my absolute top.
And, finally, I don’t want to not mention the DX5. The DX5 is still great, but given that for just $80 US more you can get what I consider to be the best value in this whole roundup for that little bit more money, I just think the M500 makes so much more sense than the DX5.
Let’s not quite stop there just yet. I’m not going to crown any of these as the ultimate winners because there’s a bit more we need to talk about.
As you can probably see at this point, none of these are perfect. Deciding which of these is best is going to come down to how you’re going to use it, what you prioritize, what you’re using it with. There are lots of different variables, so let me try to sum everything up now and pull it all together into a coherent picture.
Starting at the bottom, in terms of budget, is the DX5. It’s a good solid unit. I will still recommend it for that <$500 market, but it’s really outclassed by everything else here.
The SMSL M500 Mark III is my clear favorite in terms of price, features, and performance combination, but it is worth remembering that it doesn’t give you a huge ability to upgrade with external amps, and if you are switching regularly between the headphone outputs and the line outputs, it is a little bit of a cumbersome process. It’s not a big deal. It’s a couple of presses of a button, but it’s a bit fiddly. If you want to just change on the fly, the DX7 Pro+ is the easier product to use. If you’re going to constantly switch between headphones and the line out, it’s much easier to switch than the M500. From a pure sonic perspective, I still think the M500 is the better-sounding device.
The EF400 is probably the best-sounding product on low impedance headphones. For some reason, that sound changes with high impedance headphones. It doesn’t work particularly well with IEMs, and it’s got no features to speak of other than oversampling and not-oversampling. It also has no preamp functionality (the volume control on the front is only for the headphone outputs).
And then, finally, we’ve got the FiiO K9 Pro ESS here, which is not as good as the M500 or the DX7 Pro+ from a pure all-in-one driving-a-headphone point of view. But it gives you a fantastic set of features, and it’s also the best of all in terms of being able to provide a variable line out and some of the best sound coming out of the DAC in this entire roundup.
And so if I were going to choose one of these for myself, it would be the M500 for versatility, the EF400 for pure headphone driving sound quality (unless it’s high impedance), or it would be the K9 PRO ESS for maximum versatility (but that would be with the assumption that I was going to be running external amplifiers as well).
I’m not knocking either of the TOPPING units. I think they’re both really solid devices. They just happen to be outclassed by a slightly cheaper M500, a slightly better-sounding EF400, and a slightly more versatile K9 PRO ESS.
Ultimately, there are no clear-cut winners here. I very rarely do clear-cut winners, but there are some really strong standouts. The M500 for me is the hero of this roundup. This is the one that I’m now most likely to have on my desk.
Happy listening, and I’ll see you next time on Passion for Sound.