On turn on and turn off, there is a slightly audible click. This is the relay inside of the DX90 and normal. So do batteries make a difference? Some say they hear a difference using the OEM Samsung battery for the S3. Opinions matter. Can you improve what you hear by using better or different monitors that you are using? Some earbuds just don't cut the mustard. It makes sense to have a more densely packed thread with impressions and reviews of the DX90, now that it is out. I will post my review here and some thoughts and hopefully, it will stay on track. New firmware and drivers: Right Here! Lurker0 modified FW: Here Review sample until I buy it. Bought This DAP has two of the latest dac chips from Sabre, the ES9018K2M. There will be a dual core CPU for fast scan times and performance. Amplification is op amp based with output buffers, the BUF634. Same screen as the DX50 and UI, which will be very polished. S/N ratio, and exceptional 119 (added 3/28/2014) Crosstalk 115 7 op amps and 2 buffers (BUF634). DSD converted to PCM, coax out 24/192. New Custom made jacks. Very high quality, with an extremely good grip on the plug and rated for over 10,000 uses. Case, same as the DX50. This will be an extreme amount of power for digital decoding and sound in a very small package. USB music and OTG support. 8gb internal storage, which for me is fine as I prefer to change my music out and having 128gb cards makes that easy and pretty cheap now. Price: $419.00. I can only imagine this will be a very high performing DAP, obvious with iBasso's track record and hardware being used. Review 4 5 2014 DX90 Review It should be easy to review the DX90. The best evaluation I could do would be to suggest that you listen to one. That isn't what a review is about though. And there are times when people aren't interested in purchasing something, they would like to know something about the item, for interest sake. For me, what makes reviewing the DX90 more difficult, besides restraints on my time, is that it does so many things differently. To my ear it doesn't fit a mold, nor is it a progression of a line or a step up or down from some other DAP. I find I need to explain new terms, or to define terms in a new way that to me, is how different the DX90 is. I hear music not as something canned and electronically presented but I hear music for the sake of music. Minor occurrences, the sound, in a recording, are presented as important to the role of what I hear as the main figure, or theme. As a story has an antagonist normally the counter to the protagonist with both built on so you can understand in more depth their characters and you have the foils, who are figures that provide the fill with much less is known about them and less is built on them but they add body to the story. So it goes so much of the time with music I have heard. The main singer comes through, the instrument and you have all the supporting singers and instruments, sometimes taking their turns but you have the main drive, the nature of what the story is about. To have a story with all characters built, would be a joy but often too time consuming and sometimes unnecessary, unless it is a very simple outlay. The DX90 is able to pull from the recording, when well done, all the characters and lays them out to be heard in a dynamic space and time that creates and auditory image that belies the recording. It does not lay bare the music with intolerance, that drives a wedge between you and the music but brings the music to a closer and more emotionally satisfying place. I often listen to Neil Young's live recordings that I have heard so many times before. With the DX90 I am not separated, I am there, and it is mentally tangible. Recently I have started listening to Greg Brown on his solo recordings. Brown's voice, which is so individual, drives the words sings. His guitar carries the line and you can feel the connection. On these recordings you can sense the space dynamic drive of individual sounds as they emanate from the space they occupy. I have been using the Fostex TH900 and the Hifiman 560 quite a bit in conjunction with the DX90. I also use the ESW10 JPN. The Fostex and ESW 10 are rewired with Whiplash's new gold plated silver that I find that this gets the most out of the phones and gives me the reference I am after. The Hifiman 560 is used with either the stock cable or the copper cable that comes with the HE-6. These are the main phones I have used to this point. I have tried several amps, my favorite the fi.Q with the DX90 but I don't find it necessary, even with the HE-560. The amp section of the DX90 is a marvel. I couldn't ask anything more out of a portable amp. By using separate amps, I was able to get a handle on what the dac section and amp section are doing and what each is doing is superb. This is a case where both compliment each other. All my listening impression that I present here are done with the DX90 in total, nothing added, nothing taken away. I write here that the dynamics of the DX90 are the best I have heard from a DAP because they are personalized to the music, the performance and not generic. There is no compression of the sound, no bleeding of frequencies, no enhancement. The bass articulates, fluctuates to the recording. The mid frequencies give justice to the human voice or anything else that falls with their realm. Highs, to my ear are extended and without edge, glare or unnaturalness. In fact the entire sound is natural. With the S/N ratio of 119 and a crosstalk of 115 comes advantages. The DX90 has a silent acoustical background that builds the music, the placement, if it is close or far off sound is replicated and offstage sounds are realistic. Take from my review what you can, what you will. For me the DX90 takes the recording you hand it and gives you back music and that is an experience I can live with every day. ------------------ 4/17/14 I think that what some may be hearing as a black background or the difference with the DX90 and a few other daps, is that the DX90 is picking up everything on the recording. You get ambient sounds, which would give the impression of not as black a background but it is possible that black background doesn't really exist. I hear the same thing with the Hugo, and I don't know of a much better translator of music than the Hugo. I hear ambient movement, sounds that have been captured in the recording but often lost in the translation. I think that is one area the DX90 excels with, capturing so much of the detail of the recording, not loosing in the electronics and then presenting it to be heard, musically. With a S/N of 119 and crosstalk of 114, if everything else is done right, so much will get through of the original recording. A very low noise floor will get out of the way of those ambient cues, which to me, is what is happening. As mentioned, I also hear this with the Hugo, which I am glad I purchased, though expensive, as it gives me a great handle on a top digital converter to analogue. I would not describe the Hugo as a black background, I hear the space which gives a much greater rendition of the original event.