Why did this just happen ?

Folks ,

I have been using an old (2012) iMac with a 1TB SS drive for years. It is connected to an old Benchmark USB DAC that feeds my refurbished(2X) Audio Research SP IX mark 2 preamp into my Quicksilver KT88 mono blocks that feed my Pro Ac SE’s. 

I just bought a used 2020 MacBook Pro($400.00) to replace the old iMac. I connected it to my USB DAC via a usb C to usb converter.

AND BAM ! The resolution is stunning. I would equate it to a $5K upgrade in any part of my chain. It is truly an ear opener.

What did this ?

The USB C ?, The MacBook isn’t doing anything but output the data to my USB DAC.

I would love to hear from any of you who might know the reason for this wonderful improvement.

Eugene