USB improvement gadgets - a survey

[esldude]

http://archimago.blogspot.com/2018/12/measurements-intel-i7-pc-and-raspberry.html#more

 

http://archimago.blogspot.com/2018/12/measurements-raspberry-pi-3-b-as.html#more

 

 

6 hours ago, semente said:

There's an effortlessness and a clarity to the sound that are just delicious!

 

Wonder what creates the effortless clarity?  My guess is the only electrical changes are in the organic components.  

[esldude]

23 minutes ago, semente said:

 

That is a good question.

Maybe this can help explain why? http://archimago.blogspot.com/2018/05/measurements-computer-usb-5v-power.html

 

I've often mentioned the friend that used to optimise gear. Changes to grounding and power supplies did have an impact, sometimes quite significant, even in unsighted listening sessions where a few of us would compare two of the same gear, one unmodified.

 

I am quite sceptical of tweaks and foo in general and didn't have any expectations, nor did I invest any serious money (£50 at most) because I already had the PSUs around from my Raspberry Pi setup...

No that doesn't explain anything.  It shows there is variable noise on USB connections to different devices.  We knew that.  But how much does that get thru to the analog output of a USB connected DAC.   That is the signal we listen to you know.  The later measurements show no measurable difference in the analog output.  Would be nice if Archimago had those other computers to run the test with all of them.  I'd expect from other such measurements that the output would be clean with all of them.  

[esldude]

47 minutes ago, semente said:

 

What about how noise affects the D/A conversion, Isn't that a possibility?

 

I agree that measuring the output would provide more information. I could always capture a 48/16 of the output with my lowly UCA222 if you wish, but it may not be transparent enough...

Though to be honest I'm not looking forward to fiddling with the connections again for a while.

That is part of the point of archimago's tests.  There appears to be no effect on the DA conversion that is large enough to matter.  Noise on the USB varies, but DACs seem able to reject most of that or enough of it to not be a problem. 

[esldude]

12 hours ago, Summit said:

 

Yes of course.

 

Some people will deny that what’s upstream of the DAC matters and instead tell you that the buffer and relocking in the DAC is enough.

The DAC does not  reclock. It is the only clock. USB does not have an imbedded clock for the DAC.