An Update

In order of Sound Quality

1. DT770 250 ohm > JLH 1969 Headphone Amp > TDA1387 x8 DAC > MacBook Pro.  Sounds natural and easy, not the largest sound stage, not that large a range, great left / right separation, very musical.
2. DT770 250 ohm > JLH 1969 Headphone Amp > iFi Nano > MacBook Pro.  More digital, sharper
3. DT770 250 ohm > JLH 1969 Headphone Amp > HiFiBerry DAC+ Pro > Raspberry Pi.  Sounds small, not rich, compressed and confused, all the information is there, but not musical.

Also tried all of the above using the Sony MDR-7506, small soundstage, brittle sounding, too close