Hi All,

Today is not going to be a full review, but some quicker impressions. The product we are taking a look at is another item from FangSound, whose Ariadne amplifier I reviewed recently. FangSound sent along their small dongle DAC/Amp, called the Prometheus, inside the box with the Ariadne to let me check it out during the review period.

The dongle, small DAC/Amp market has absolutely exploded in the past 10 years, but the past 5 years in particular. I remember back in 2015 I bought the LH Labs Geek Out V2, which claimed a power output of 1 watt (into 16 ohms if I remember correctly) and it did actually sound great. The issue was the 3d printed plastic case, which, due to the 1w power output and associated heat dissipation heating the plastic, lacked any real structural integrity. The reason I mention this is that the FangSound Prometheus also features a 1w power output, but has a build quality and sound that easily surpasses the LH Labs Geekout of old. It’s been neat watching the headphone hobby change since I first started with a pair of Grado S325 back in 2012, and the amount of both choice quality equipment out there these days is truly staggering in comparison.

The Prometheus has exactly the same feel, look, and build as the much bigger Ariadne. It feels solid and well built. There are no moving parts, no volume control, no power buttons. It has a simple USB-C input, with both a 3.5mm and 4.4mm balanced output. I’ve mostly used the 4.4mm balanced output in my testing. I’ve used both easy- and difficult-to-drive IEMs, as well as easy- and medium-difficulty-to-drive headphones in my testing with the Prometheus. Out of all the tiny DAC/Amp I’ve used, the Prometheus is my favourite thus far. It’s so incredibly simple, but it has a solid power output for its size, and can handle basically any IEMs you throw at it, whilst also working with easy- to medium-sensitivity headphones. I wouldn’t recommend it as a primary solution for hard-to-drive headphones; it doesn’t excel in that area. However, if you need an option for travelling, in hotel rooms, or just as an incredibly easy-to-move-around-and-use option as a second setup at home, for less dedicated listening, the Prometheus fits that need perfectly.

The Prometheus sounds slightly more neutral than the Ariadne, lacking a bit of the slight warmth and glow of the full-size amp. Featuring the ESS 9039 Pro chip as its DAC, the Prometheus has a very clear, clean, and detailed presentation, but thankfully doesn’t wander into sharp or overly bright territory. I personally feel some of that ESS Sabre preconceptions of bright and harsh sound from the 9018 era have been mostly resolved both on ESS’s end and also people implementing the chips. I’m sure it still exists in some products, but I’ve not found it to be an issue in any way with the Prometheus.

One thing to mention is that the Prometheus, due to its 1w power output, gets hot. Not enough to burn you, but it’s definitely warm after 10 minutes of use. Also, due to the higher-than-normal power output, is battery usage of your device. This is something to consider if you are using it with a phone, and on a long flight or something similar. Try doing some testing before your trip to see how fast you burn through your device’s battery, and bring a charging cable if need be.

The only real negative I can come up with after spending time with the Prometheus is the price. Retailing at $ 560USD, it’s a very steep asking price for a dongle DAC/Amp. The Prometheus is a very high-performing DAC/Amp, especially considering its size, and does outdo most of the competition in terms of specifications and build quality whilst also sounding great. With that being said, I do think a lot of people who just need something small and affordable for a second system or third option as a backup will probably go elsewhere. However, if you are primarily an IEM listener vs full-size headphones, or if you know that a small dongle DAC/Amp is going to be your primary source for all your listening, then the MSRP begins to make a lot more sense.

I really like the Prometheus. It’s certainly the best Dongle DAC/Amp I’ve personally used. It’s really well built and incredibly simple, with no moving parts to break. It’s surprisingly powerful, and presents music in a really clean, clear, and crisp manner. It’s more neutral than the larger full size Ariadne and very detailed, and will work incredibly well with basically any IEM, whilst also working with easy to medium sensitivity headphones. If price isn’t a factor for you, or if you are going to be using a dongle as your primary source, I’d definitely recommend checking out the Prometheus. Well done FangSound!