I have been looking at all the new DACs for one to mod but until now have not seen anything worthwhile.  The Gustard X20 is the real deal.  $870 delivered from China with 2 ESS DACs in dual mono mode (8 parallel DACs per channel)......it looks like a $3000 product and according to the guy in the below link beats the Schiit Yggdrasil (Yggy) and the Auralic Vega.....these two heavy hitter DACs ($2300 and $3500) are seriously respected DACs in their price range. This DAC can handle Quad speed DSD (tested with driver from DIYinHK) via USB and supposedly Octal speed DSD via I2S as well as the usual 32/384 PCM.  It has a digital volume control with remote so could be used to directly drive an amp.  Check out these links: 
Gustard X20 DAC mods

 Here are some AC power mods that are simply mindblowing:

1. Bypass the fuse with copper foil (or use audiophile fuse if this scares you)....now I even bypass the fuse holder for even better sound.
2. Remove the hardware from the transformers and raise them off the chassis using doubled up carboard donuts.  You can then use nylon nuts and bolts without much tension to hold them in place.
3. Twist all AC wires tightly (both into and out of both tranformers and between front and back boards).  You have to remove the heatshrink tubing from the wire before you can twist them.
4. Remove the input AC filter.
5. Remove the 110/220 volt selector switch.
6. Remove 5 AC connectors inside the unit.  You have to desolder and remove the circuit board mounted to the AC inlet.
7. Remove the power switch.

If you do all 7 things above then you will have both transformers hardwired directly to the AC inlet.  Black wires from transformers go to neutral and white go to hot for 120V.  If you have 240 then use black to neutral and red to hot.  Tape off end of unused wire. To turn on the unit, you plug it in.  To turn it off, you unplug it.  There is no reason to turn it off....it does not use much electricity.  The sound is now incredible.  This has to be heard! 

If you can solder and are adventurous, you can do these first 7 yourself.  The first three are easy and you do not need to solder.....they will show you the promise of this thing. Pic below is showing all 7 AC mods and you can see the custom digital cable installed as well.  

Pic below showing cardboard underneath transformers and nylon hardware (not tightened for best sound).

Here is a link to where you can buy it:
Another link where you can buy it and more pics :
Also, Please check out this link about upsampling PCM to DSD with HQ player and my response about using the Gustard for the DAC in that senario at the top of page 11:

5-17-2016:     Taking orders now!   A month ago an old customer compared his not even burned in stock Gustard to his Yggy.....he sold the Yggy....the stock Gustard is better!  Wait till he does some mods!...and he will...he is a tweaker...it will blow his mind!  Link to new thread on What's Best forum:

Below is the before picture

Basic mod package :   $425 plus return shipping

1. All 7 AC power mods listed above.....incredible!....incredible.....incredible!!!!  Included is a complete byass of fuse holder and fuse.......audiophile fuse extra.
2. WA Quantum Chips on power supply caps.....noticeably more detailed and transparent.
3. Damping of loose mounted caps, many electrolyics,clock, etc...... more focused and clear and real.
4. Changing rectifying diodes on output board to damped soft recovery types......OMG, so much more 3D and inner detail
5. Remove the digital cable between the board and install low jitter Crystek clock right at the DAC with modified Wima bypass cap with WA Quantum chip installed.

This mod has no power switch.....you plug it in...it is on.  No need to turn it off...uses little electricity.  For those that must have a power switch we can install one on the back panel for TBD price.  The switch will degrade the sound slightly.

NOTICE: If you are not using the usb input then it sounds noticeably better with the usb card removed.  Not easy to do but worthwhile (see below for instructions).  If you plan on just using coax/AES or I2S input then I can remove the card for you at no additional cost.  In fact, if you are never planning on using the usb input then buy the DAC without the usb board for $829....save some money.

Turn around time on Mods is 2-3 days in house.  Please see Gustard Pro page for latest information.

How to make your own PC for super audio playback via HQplayer.....please click here:
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