Preamble:
At HiFime, all started with the production of the Tripath TK2050 speaker amplification chip. Nowadays they are mostly known for their portable DACs that use valuable electronics but remain a good price-performance ratio.
I would definitely say for myself that I really like ESS Technology’s SABRE audio chips – in some applications, their sound is very crisp, dynamic and fast, however realistically speaking, one should rather expect smaller differences between various DACs (if any) instead of worlds, as long as elementary things such as a neutral frequency response are given (correctly metrologically volume-matched, the differences among various devices are usually rather small and sometimes small enough to be considered inexistent when it is about transparency, soundstage, subjectively perceived tonality (because of “noise floor modulation” effects) or speed, and most modern audio implementations and applications provide a linear and clean signal wherefore real differences in terms of audio quality are usually rather tiny (objectively speaking)).
Nonetheless, I still like the “typical SABRE glare” some applications have, with their fast, clean and crisp treble, despite measuring ideally flat, wherefore I really love the iBasso DX90 and
HiFime 9018d, although I usually don’t use the latter to directly drive sensitive in-ears because of its noise floor.
Recently, HiFime has released a new DAC that is using a 9018 SABRE chip as well. That new model is a very small and inexpensive (semi-) transportable DAC with digital optical S/PDIF input as well as analogue 3.5 mm Line Out socket (
http://hifimediy.com/SPDIF-9018-DAC). It is getting its power from a regular mains adaptor or mobile battery pack that has to be connected to the micro USB socket (that is really just there to connect a power supply, as it does
not act as USB DAC).
This review is going to cover how clean, linear and stable the signal of HiFime’s optical 9018 DAC is.
Before I go on with my actual review, I want to take the time to thank Nick from HiFime for providing me with a sample of the optical 9018 DAC free of charge in exchange for an honest, unbiased evaluation.
Technical Specifications:
Price: $59.00
Input: Digital SPDIF optical signal, accepts all sample rates up to 192kHz, 16, 24 and 32 bit
Output: Analog audio through 3.5mm connector
Sabre ES9018k2m DAC chip and SABRE9601 headphone and line out driver
Requires power from microUSB (not included). Note: It doesn't work as a USB DAC! The microUSB connector is only for power.
Works and sound great with most headphone (including low impedance IEM and high impedance headphones) and all line level devices (preamps, amplifiers)
Ultra low noise regulator LP5907 with added noise reducing aluminium solid capacitors (NCC PSF series)
Optimised 4 layer PCB for greatest performance
122dB SNR
110dB THD+N: 2V rms @ 600 ohm load
100dB THD+N: 30mW @ 32 ohm load
No DC blocking capacitors on the output
Power usage: <80 mA depending on sample rate and volume
Dimensions:5.5 x 3.5 x 1.8 cm (without cable)
Weight 30g
Delivery Content:
The envelope contains solely the DAC. The customer has to get the power supply (most phone chargers will do) as well as interconnection cables by himself.
Aesthetics, Build Quality:
The DAC’s enclosure is made of black plastic that features a recessed HiFime logo on its upper side as well as a second logo along with a “Made in China” sign on the bottom.
The two shorter sides contain two LEDs and of course all connector sockets that are conveniently labelled with white colour.
The enclosure’s edges are nicely rounded and the DAC is very small. The matte black plastic feels very nice as well as sturdy and is comparable to the Xbox 360’s controller’s material.
Although the DAC is very plain looking, it is very sturdy and neither fragile nor rickety, ulike some other inexpensive products.
Features, Connectors:
One side contains a micro USB socket for the power supply as well as an optical 3.5 mm S/PDIF input. The opposite side hosts the 3.5 mm audio output plus two red LEDs.
The right LED is permanently shining and signalises that the power supply is working whereas the other is only activated as soon as an audio signal is incoming. What I really like is that both LEDs are just modestly shining and far from being bright and obtrusive.
All connectors sit firmly in the sockets.
left picture: power on, no signal right picture: power on, signal incoming
Sound:
The source devices I used were my Windows 7 laptop, Pioneer PD-S 701 CD-player as well as iBasso DX80.
The amplifier I connected to the HiFime was my gain-reduced Leckerton UHA-6S.MKII with the main in-ear being my UERM. However, I also used the Triple.Fi 10, Shure SE846 and last but not least Pai Audio MR3.
Frequency Response:
As one can see, the output frequency response is unaltered, flat and therefore just as it is supposed to be.
As usual, I won’t publish my other measurements as my sound card is not reference-grade and only accurate when it is about measuring frequency response plus frequency deviation (loaded and unloaded). Nonetheless, measured dynamic range, noise floor and distortion values with my soundcard were around -115 dB and crosstalk around 84, which is simply the best my soundcard can measure, what of course means that the HiFime DAC is metrologically better but my soundcard won’t capture it.
Hiss:
My Leckerton is basically hiss-free in Low Gain setting, even with super sensitive in-ears. In order to that a DAC’s noise floor becomes audible when connecting it to an amplifier, it has to be quite badly constructed and the HiFime is fortunately not (which is however not much surprising) - the signal is flawlessly clean and hiss-free, but my RMAA measurements already indicated that.
Transparency, Precision, Soundstage:
Now to the very subjective part of my review. My opinion and experience regarding the sound signature of source devices and amplifiers goes like this: there is an existing audible difference between various devices, but it shouldn’t be overrated – simply because the basic character of a headphone won’t be completely changed (if the circuit follows a clean design philosophy), but sometimes rather “shaped” a little and is extremely subtle in many cases and is (in most cases) just slightly present (if even) and not huge like totally different classes.
Now let’s continue with my subjective impressions and observations:
The DAC sounds just like it should: transparent, unaltered and very clean. More specifically, one could say that it doesn’t “sound” at all, which is a good thing as it means that an uncoloured signal is put out.
The bass is quick and arid, the sound is transparent, the soundstage is three-dimensional with identical width as well as depth and the treble is crisp.
Does the HiFime, feeding the Leckerton, also have the “Sabre glare” some implementations slightly tend to have? I would say no, it does not and the signal is simply clean, neutral, clear and genuinely transparent. Some slight “Sabre sharpness” as my iBasso DX90 has to a little extent (along with a soundstage that is wider than deep), an especially fast treble as the Zorloo ZuperDAC has or some slight Sabre glare the HiFime 9018d (which by the way sounds like my DX90 to me, except for the HiFime’s very audible noise floor when directly connecting in-ears to it) shows, are things the optical S/PDIF HiFime DAC lacks entirely – all I am hearing here is the on-site upper treble brightness my UERM has when comparing the HiFime to the other mentioned devices that show some “Sabre glare” with the in-ears being plugged into their headphone output socket (nonetheless I should mention that the difference between the just-mentioned devices is (objectively compared) rather small and definitely not huge).
Short Comparisons:
Needless to say, the same audio files were used, along with the same measured volume setting with the Leckerton.
Vs. iBasso DX90 > LO -> UHA-6S.MKII:
Comparing the iBasso’s internal DAC to the HiFime, I couldn’t find any objectively reproducible difference – the output sound of the DX90’s Line Out is just as transparent, spacious and clean as the HiFime’s when connected to an S/PDIF source.
Vs. FiiO X3 -> LO -> UHA-6S.MKII:
Here I could just say the same as just with the DX90 – over the Line Out, there are no objectively reproducible differences I could make out.
Vs. Shanling M2 -> LO -> UHA-6S.MKII:
The same thing goes for here and both the M2’s Line Out as well as the HiFime output a comparably clean, transparent signal.
Vs. iBasso DX80 -> LO -> UHA-6S.MKII:
The somewhat analogue, smooth and slightly warm sound character of the DX80 is also a bit present over its Line Out wherefore the sound is somewhat warmer and less “crisp” as with the HiFime. In terms of transparency however, both are identical, nonetheless the DX80 sounds somewhat smoother and more “organic” in the treble when used as Line Out source. Is this a better or worse thing? It is neither of both and just a matter of preference.
When it is about soundstage, I couldn’t detect any objectively reproducible difference between both devices.
Vs. PC -> LH Labs Geek Out IEM 100 -> “LO” -> UHA-6S.MKII:
In terms of transparency, both are on-par, however the Geek Out’s sound is smoother by a smidgen, though without shifting to being ever so slightly warm at all. The Geek Out’s soundstage appears a slight bit deeper.
Vs. Laptp/CD-Player/DX80 -> S/PDIF -> UHA-6S.MKII:
So here, I compared the HiFime to the Leckerton’s internal optical S/PDIF DAC. Quite often, the UHA-6S.MKII’s internal DAC is said to be averagely transparent, so I cannot say whether the following comparisons contain some minor bias or not:
With metrologically identical levels (the Leckerton’s internal DAC puts out less voltage and is therefore more quiet than when purely used as amplifier), I would also say that the HiFime sounds somewhat more transparent with in-ears and that the Leckerton’s soundstage is a bit more compact and less clear – however, there is no night and day difference here again, nonetheless I would say that the Leckerton’s DAC is somewhat inferior in terms of transparency when used with sensitive in-ears.
Conclusion:
With their latest creation that uses an ESS 9018k2m chip, HiFime has introduced a small, inexpensive DAC with S/PDIF input. The sound is flawlessly neutral, transparent, clear and clean.
Who is looking for such an impeccable optical DAC because of his/her source device not putting out a linear/clean signal and/or not supplying enough voltage over the Line Out but has got an S/PDIF output should definitely look at this DAC from HiFime.
Therefore it is extremely easy for me to unhesitatingly recommend this DAC and to give it a perfect rating with 5 out of 5 possible stars as I do not see any area where it fails.
Ah, I see.
With the HiFime, you should get comparable results (slightly less "messy" and "confused" sound).