Had mine for a few months now, a nice dac and quite a bit better then my Yulong DA8.
The Yulong sells for around the same price.
General description
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The parts used in the DAC are of very high quality and test out to be genuine.
The advertising copy for this dac has a lot of buzzwords, I found to my surprise it did not fully describe the features of the dac.
Hirez PCM DXD and DSD256 works as advertised, using it with Audirvana and the Raspberry Pi 2
One major thing the standard LKS blurb did not emphasize was that the USB interface was galvanically isolated as was the I2S interface.
This was a pleasant surprise when I opened up the dac.
Technically this dac is much better implemented than the previous MH-DA002 and avoided the hamfisted use of the old linear regulators.
This dac uses the LT1763 ultralow noise regulators.
Each dac has the critical AVcc 3.3V supplied with its own regulator.
The 1.2V digital and analog core supplies share the same requlator, unfortunately, but each dac has its own regulator,
a little annoyed as to why LKS decided to penny pinch at the last moment, old habits die hard...
Sound quality
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Presentation especially presence of the performance is much better than the DA8, the stock LKS tends to the bright side like a lot of ES9018 units.
On really complex passages the Yulong can sound confused and incoherent but the LKS is not affected, bass extension and lower midrange presentation is superior to the Yulong, material like the double bass and cello sound quite muddy on the Yulong in comparison.
I am using this with the HD800/Mjolnir and SR009/SRM-007T2. The former combination is unforgiving on bright material.
Upgrade potential
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Where the LKS comes into its own is when a modest amount of modification done.
The bright topend of the ES9018 is made much worse by the use of the Crystek CCHD575, this is a femto clock.
The sound is hard and etched. I replaced it with Crystek CCHD-950X which give it a more balanced presentation.
The stock LKS (as with most Sabre32 DACS) is not very liveable on the HD800/Mjolnir combo.
The Crystek 950X makes both the HD800 and SR009 sound good without any treble hardness.
The stock opamp used in the current to voltage converter idles at about 7-8mA,
the ES9018 used as a 8-channel mono device requires the opamp to handle up to 32mA of current.
LKS used the opamp in virtual earth configuration and has to sink and source this current completely,
otherwise the ES9018 will flip and flop from current mode into voltage mode and back again.
This means part of the output stage of the opamp is no longer operating in class-A beyond 25% of its operating range,
that means the opamp drops out of Class-A operation at round 7-8mA.
The replacement opamp is a discrete unit from Sonic Imagery which operates in Class-A up to 30mA.
Still a little short of the ES9018's fullscale output but is significant step up from the stock unit.
Replacing the I/V opamp improved the transient attack of the material while taking the hard edge off the sound,
quite surprised how mellow the HD800/Mjolnir combination sounded without losing any of the clarity and transparency.
(Mellow, Mjolnir and HD800 is something I would not use in the same sentence in normal circumstances) .
On the SR009. I can hear the initial transient of hammer hitting the membrane kick drum, normally it is a dull thud on the Yulong.
None on the clarity is lost on the SR009.
The other major improvement came with replacing the integrator caps in the I/V converter with matched polystyrene caps.
The stock Wima FKP2s were quite marginal. Some of the copperfoil polystrenes are visible in the pictures.
The unbalanced section used 2 dual opamps which were replaced with the NJR Muses01 FET opamps
I have also replaced the main output filter caps of the various voltage regulators of the digital parts of the dac with Sanyo OSCONS and Nichicon R7 FPCaps. The original Nichicon Muse caps were really quite unsuited to the job of providing low-ESR and high ripple filtering capability to the fast changing power demand transients of the digital side of the DAC.
Picture of the DAC internals
Closeup of the I/V converters.
Future mods
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Vishay Z-foil resistor for the I/V conversion resistors
Vishay foil trimmers for the offset pots
Future comparisons
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Waiting for Schiit to get their schiit together and ship the Yggdrasil so that I can get one and compare.
