cliveb wrote: > Please can you speculate as to the mechanism by which a linear 5V supply > gives an improvement over a SMPS 5V supply? > Bear in mind that the DIGI+ SPDIF output is transformer coupled and > therefore galvanically isolated from the DAC it feeds, so noise > transmission to the DAC via the ground plane isn't likely to be the > cause.
In this case since it's audible... my theory there's less distortion in the spdif square wave signal (hence less errors on the other side) Though this guy did some nice simplified graphics on spdif and where it can go wrong: https://www.youtube.com/watch?v=grzoqEb2KMk Here the 5V supply might more effective than when used on the touch... I honestly thought it was a little subtle to even care (on the touch), but couldn't hurt right? (this was 3-4 years ago) ...So I still have that linear supply, so figured try it out on/repurpose it for the pi/digi+ Now on the pi, if you power it from it's usb port, there's protection circuitry, a fuse, and a tiny switching supply (in addition to the typically cheap 5V usb supply) This setup the pi's switching supply,fuse,protection is all bypassed (you can power the pi from it's GPIO pins) -- in addition to the digi+ not pulling power from the pi-- CiAudio VDC-SB - raspberry pi b+ hifiberry digi+ (BNC added, removed TOSlink) piCorePlayer (play song from RAM) - trumps sb touch sound quality --> Use as spare/reference: Touch (EDO / screen off plugin, removed analog coupling caps, removed toslink, added output transformer & bnc jack ) PSAUDIO TRIO C100 - DLIII (Cullen full upg AMP/DAC) - Energy Veritas w/Custom X-overs - 2x Martin Logan Descent i - Dectet - Cardas Clear Audio/Power ------------------------------------------------------------------------ sckramer's Profile: http://forums.slimdevices.com/member.php?userid=20311 View this thread: http://forums.slimdevices.com/showthread.php?t=104518 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles