The Border Patrol DAC - Maybe linearity in a DAC is bad ... Spitballing


Hi Everyone,
I've been thinking about a few things related to DAC's and how they behave and how we hear. Also thinking about a couple of audiophile comparisons I've heard and how we interpret what we hear.

Let's talk about this simple measurement called linearity.

In a DAC what we mean is that as the magnitude changes the output changes the same amount. That is, if the signal says "3 dB softer" you want to get exactly 3 dB softer output on the jacks.

And with modern, top tier DACs this is usually really good until around -90 dB where noise becomes the limiting factor.

For a long time I felt that a DAC which allowed me to hear the decay of a note, so that it fades instead of stops suddenly was the mark of a truly excellent sounding DAC.

I'm wondering if what I'm actually hearing is compression? Lack of linearity.

The reason I bring this up is that I was reading a long article about the complexities of reviewing a DAC from Border Patrol. One of the main failings, from measurements, is that it is really not linear at all. Sounds don't get softer fast enough. And ... low and behold, Herb Reichert actually makes many comments about how much more he can hear with this DAC than with others.

I'm going to link to a critique of the "scandal" so you all can get a better look:


https://parttimeaudiophile.com/2019/01/06/border-patrol-dac-revisited-audio-fur/


Also, take a look at the linearity charts in the original review. Honestly, awful. Not up to what we expect in state of the art DACs today, but ....


https://www.stereophile.com/content/borderpatrol-digital-analogue-converter-se-measurements

What do you all think? Do we need a compression feature in DACs so we can hear more details? That would make more sense to me than a lot of the current fad in having multiple filter types.

Best,
E

erik_squires
@kalali

Don't you think these effects could be explained by compression?

Best,
E


Erik, it could be but I’m sure someone familiar with the recording process is definitely more qualified to address that (valid) question. The more I think about it the more the concept of “contrast” especially measured as a ratio, makes sense to me and I feel it also applies to other audio components. It’s a metric that I don’t think is captured in the typical audio-centric measurements such as frequency response, etc. It’s sort of like putting more “emphasis” on certain areas of musical “texture” which may or may not be directly related to the amplitude at that frequency. Again, perhaps experts like Ralph, Roger, or Steve, etc.,  can comment as whether or not the concept even applies to audio. Interesting analogy nonetheless.
Subjectivist chiming in who bought the Border Patrol SE Dac and returned it....

Apparently I like the decay and transparency of a typical DAC because I felt the Border Patrol sucked the life right out of my system.  It was coloring the sound but definitely not to my tastes and it made me want to leave my system turned off.  Anyone who thinks DACS all sound the same just needs to plug this one in!  

I honestly don’t get the rave reviews for it but hey, everyone’s tastes are different.  I certainly would never recommend this as a blind buy for someone though.

It’s very simple to explain how a DAC can "remove" musical content. It’s not that it’s literally removed, but rather that the resolution of one is superior, allowing to hear deeper and wider into the soundstage, thus capturing the extremely minute character of the reflections off the walls of the venue. (I will add that this is simply discussion of the phenomenon, not my conclusion re: these two products.) Without referencing the article I believe that is what is intended, and perhaps was not stated so eloquently. It is a very regular occurrence when using components of different manufacturers. All components vary in not just that respect, but many others.

See what I said about the comparison of the Benchmark DAC3 DX to the BP DAC SE at Dagogo.com

They are substantially different builds, and have substantially different sound characteristics.

Also, feel free to reference the discussion in the Cable forum regarding Doug Schroeder Method Double Interconnects.

Note, please that Border Patrol has indicated that this is NOT a suitable method for its NOS DAC. I have been using it very effectively with the Benchmark DAC3 DX. Note that Benchmark has not officially endorsed Schroeder Method; this is my exploration/research. This is an entirely do at your own risk activity. But, the results are stunning.


If you are tempted to rebut me using theory, know I am not interested in arguing or debating my viewpoint or methods. :)