I recently had the ability to audition the BorderPatrol DAC (hereby referred to as the BP) in my system at length. It is awesome and my favorite to date out of the many DACs I have owned. For those not in the know, the BP is a non-oversampling converter using the Philips TDA1543 chip. According to @MrTeaRex 'the chip is garbo' but thankfully he's behind bars and we can appreciate this DAC without him. Other interesting bits: there is no output buffer. The output pins of the TDA1543 are capacitor coupled directly to the RCA sockets. This is a ballsy move in today's modern hi-fi market as it leaves us with a measured output impedance of >2kOhm. A line stage or amplifier input impedance of >50kOhm should be present to avoid an impedance mismatch. So how can someone put a $5 chip with no analog buffer into a small chassis and charge over $1000 for it? The answer is supposedly in the power supply, which BorderPatrol makes a big deal about on their website and ad copy. I counted 4 transformers in the power supply, two mains transformers wired in parallel and two chokes. The exact PSU arrangement is unique and a bit beyond my wizardry level but it's supposed to be a 'hybrid' with one half traditional solid-state diode rectification and the other half featuring a EZ80 tube rectifier. The tube rectifier can be switched in and out of the circuit easily using a push button on the front. I'm not clear on the technical benefit of such an arrangement but I can say I seem to subconsciously prefer the tube switched in. The sound gets a bit richer. It seems like overkill to feed a little TDA1543 DAC board and S/PDIF receiver with such a power supply but according to BorderPatrol that's what the other designs miss. The BP DAC was recently the subject of controversy due to its coverage in Stereophile, which featured an initial positive subjective review; a hammering in the objective measurements section; and a follow up 'second look' from a different writer which could only be described as a thinly veiled hatchet job. Yes it measures like its defective, but it sounds great! The words that come to mind to describe the BP DAC are open (as if the music playback has become 'unconstrained'), vivid (as if the music has a new sense of immediacy and presence) and unfettered (as if the music playback is not being processed or massaged in a negative way). It has more of these qualities than any other digital source I've experienced to date, and that's why I like it so much. I was pretty skeptical reading both professional and user reviews of the DAC before I heard it, as many double-edged words like 'relaxed' and 'smooth' were used to describe its sonic signature. Warm-butt red flags went off. Was this one of those 'good for jazz' but bad for everything else DACs? The following will sound cliche but the BP DAC is 'relaxed' in the sense that it is not trying to hype up any technical parameter to grab your attention. Instead the focus is always on the musical performance. I cannot really think of a better way to describe the sound of this DAC. It is capable of bite and crunch with a fantastic sense of timing and 'beat'. Jefferson Airplane and Hendrix are a treat through this DAC. Other DACs sound veiled and/or processed in comparison. Perhaps for Megadeth or Metallica I would recommend turning the tube off for a bit more crispness. It won't win any awards for bass depth or slam, a byproduct of not having any sort of output buffer. The bass is good enough for my taste for acoustic and electric music. Maybe not electronic. Downsides? The pricing scheme is kind of dumb. $1350 for the SE edition of the DAC with either USB or S/PDIF inputs is a good deal. I would personally take this DAC every day of the week over the Gungnir Multibit (either generation, with any digital source). However if you want both USB and S/PDIF the price jumps $500 to $1850. I'm really not sure how an additional input justifies a $500 price increase but the value proposition drops quickly given the limits of the 1543 DAC and the output quirks. Also, if you're one of those 'pride of ownership' people, don't dare to look inside this DAC. You will see a digital board mounted on a piece of scrap wood and transformers mounted on pieces of cork. My experience with this DAC and the Audio Mirror Tubadour have shown that I have a definite preference for the non-oversampling sound. I think it's hard to explain what a good non-oversampling DAC does well in words but very easy to overstate their shortcomings. The only way to know for sure is to try it yourself.