By my owns methods, first treating the room, after that eliminating vibrations around the gear, and lastly using crystals, and stones of my own design(you can laugh i am used to it)...
This dac will sound the same in any non cleaned house and audio system, it has sound the same in my non cleaned system : not so good...But now its sound 3-d and musically organic without any lack of details... Forget this dac, think about any piece of gear, this will be the same...Any non treated room .house, audio grid, will destruct the musicality of an amplifier or of the speakers etc... Even headphones,for example i dont like so much my non treated non cleaned AKG K 340 headphone; but now they are so good that they trash all my others headphones including 2 Stax , the reason was my non cleaned audio grid and non clean electrical house grid... Now that i have eliminated vibrations even in this headphone, and introduce some stones in the cable ,now they are so good that all negative reviews of these can made no more sense,but before the cleaning methods my impressions of the Mighty AKG K 340 were similar to some negative impressions ,for exemple lack of coherence between the drivers... Now i am in love with them...True gem like my dac...And impossible to upgrade because of multi-thousand dollars costs will be necessary... When music is already there you speaks no more about "sounds"... And i can say the samething about my SAnsui AU 7700 before cleaning methods and after...It is not the same amplifier...Now i am in love with my gear, why? Because cleaning reveal the qualities of your piece of gear...They are better dac than this French dac, better headphones that the K 340, better amplifier than the Sansui, and better speakers than mine,but after cleaning, improving their sound will cost me 10,000 dollars perhaps more not one thousand ...I listen more to music now than to the sound of my system