Wyred 4 Sound DAC-1 LE (Limited Edition) DSD-capable DAC [SILVER]


500+ Head-Fier
Pros: Smooth, Grain Free Sound. Excellent bass response. Excellent low level detail. Non fatiguing sound. Vinyl like
Cons: Could be a bit too smooth... lacking the last bit of 'air' and treble detail. Some upper mid range hardness and glare at times.
This is a review of the Wyred 4 Sound DAC-1 LE with the FEMTO clock upgrade.  I was looking to upgrade my iFi iDSD Micro portable headphone amp/DAC to a pure desktop DAC.  I no longer needed the head amp of the Micro, since I do all my headphone listening though an outboard amp.  The Micro is a GREAT DAC, but its weaknesses, slight as they may be, are an ultimate lack of control in the lower registers, and some grain in the treble, and some problems with sibilance.  One of its strengths is ability to play back every format in existence, and then some.  So, I had collected quite a few commercial examples of all the esoteric audiophile formats, including DXD and DSD256, so ability to decode those two formats in DAC was a must.  Check for the DAC-1 LE!  
The DAC-1 LE came to be when Wyred 4 Sound decided to upgrade all their DAC-1 in warehouse to more modern standards in order to remain competitive.  The old 24/96 USB receiver was replaced by a modern Amanero solution, (including Galvanic Isolation), and full DSD compatibility was added all the way to DSD256 (I don't believe DSD256 was initially added to the units at FIRST, so it is possible that some older firmware units are floating around that will not decode DSD256. As a matter of fact, my unit, while it will decode DSD256 no problem, is two firmware updates behind, which means when playing back DSD256 the front display won't display the file type properly).
In addition to the Amanero Asynchronous USB solution, the dac uses the ESS 9018, which has 8 dacs in parallel for maximum resolution.  The DAC-1 LE has a FULLY BALANCED signal chain with both balanced and unbalanced outputs.  There are, however, no preamp functions on the DAC-1.  The onboard ESS digital volume control is not accessible.  Preamp functions are reserved for the DAC-2DSD and DAC-2DSD SE, higher in the pecking order.  
As mentioned before, there is an optional FEMTO clock upgrade available, which takes the price of the DAC from $999 to $1,124.  My model has the Femto clock installed.  
Here is a photo of the back of the unit, with stickers detailing the installed options. 
Now to the meat of the review.  This is a darn good DAC.  I think it is a LOT of DAC for the price.  My immediate comparison is the iFi iDSD Micro.  Compared to the iDSD, the DAC-1 LE has notably more low level detail.  For instance, take the wow and flutter and imperfections that can be heard in the background of a recording made on reel to reel tape.  The iDSD glosses over these small details, while they are easily heard on the DAC-1 LE.  
The iDSD could get a bit harsh and sibilant on some recordings. The DAC-1 LE if anything could be too smooth in the treble.  No harshness or sibilance here.  The treble response could be described as 'sweet' on the DAC-1 LE.  Actually, the effect makes audio sound almost 'vinyl-like' at times.  Forgive me for repeating what has become something of a reviewer cliche, but, it really is an accurate description of the voicing of this DAC.  From the warm and full low end, to the smooth and rolled off treble, this is very much like an 'analog' experience.  
The DAC-1 LE is great for those long listening sessions, free from any ear fatigue.  It makes hotter recordings sound more listenable, while still doing justice to the best recordings.  MUCH attention seems to have been paid here to the internal power supply.  Perhaps more important in a DAC than anything else is the power supply. If you read through the W4S literature they talk a lot about their power supply, and I am happy to say the results speak for themselves.  This is a job well done.  
I only have one other real complaint about this DAC.  Since it uses the ESS chipset, all audio goes through internal DSP.  This means everything really sounds very much alike.  There is very little difference here in the sound of DSD and PCM recordings.  DSD recordings, while sounding great on the DAC-1 LE, are missing that last little bit of breath, air, and smoothness that differentiate DSD from PCM.  Also, it lacks the impressive transient response and attack I am used to hearing on DSD recordings.  This is one area where the iFi iDSD is very strong in comparison, since it converts DSD directly without any DSP.  That said, I would still rather listen to my DSD files via the DAC-1 LE, due to its strengths which outweigh this weakness.  Still, if native DSD conversion is a must have for you, and you want the best native DSD your money can buy, I would suggest looking to a DAC that uses something other than the ESS chipset.  
In conclusion, if you are in the market for a DAC in the $1000 range, I think you would be remiss in overlooking this DAC.  It belongs on your audition list, ESPECIALLY if you value smoothness, warmth and analog like sound over all else.  
Other equipment used in this review
CUSTOM PC running Jriver - 4 terrabytes of all high resolution music
INTONA USB Galvanic Isolator
iFi iUSB Power, iFi Gemini two headed cable
REGEN AMBER with generic LPS, Wireworld USB cables
iFi IDSD Micro
Rega RP3 turntable,  Audio-Technica OC9/ III cart, custom made step up transformer, Music Hall Phono Amp
Icon Audio Stereo 20 PP tube amp- headphone output via dedicated transformer 
Telam/Polam EL84 NOS tubes x 4
Westinghouse Black Plate 12AU7 NOS tubes x 2
Valvo ECC83 'I60' NOS tube x1
Audioquest RCA interconnects
AUDEZE LCD-X (2016 revision)