On Thu, 24 Dec 2015 03:58:31 +0100, Ralf Mardorf wrote: >On Wed, 23 Dec 2015 17:42:29 -0600, Jonathan E. Brickman wrote: >>> USB MIDI has got the risk to cause noticeable MIDI jitter. >>> >>> Does USB MIDI provide galvanic isolation? Several times I read >>> claims that USB MIDI connections aren't galvanically isolated. >>> >>> Standard MIDI connectors make usage of opto-couplers and shield of >>> the MIDI DIN connectors is open. >>Certainly all of the USB MIDI connections I have ever tested, are not >>galvanically isolated; I always get trouble with USB signals bleeding >>over where they don't belong. USB-to-DIN adapters I have used have >>been better, but not perfect. Is there a make/model of USB-to-DIN (or >>even PCI-to-DIN if it exists anymore) which you know for sure has >>opto-coupling? That would be a great boon to me. Sooner or later I'm >>going to do optocoupling for audio too, probably using a TOSLink >>setup. > >You can solder yourself or buy cables for serial port, resp. PCI >sound card output with such a connector, that have build in >opto-couplers. I remember this very good, because years back, when I >started needing reading glasses, but didn't own them, I tried to >resolder a a self made parallel port cable. I tried to add ^^^^^^^^ serial (I'm sure I corrected the "typo" before sending :S) >opto-couplers and due to the missing reading glasses, resp. a missing >magnifier, I damaged the jack. The cable worked without opto-couplers >for my serial port, but didn't work for my Envy24 sound cards. I then >ordered a cable for around 10,- € with build in opto-couplers. >I own USB port to MIDI DIN, but never measured if shield is open and >can't take a look inside, but I didn't experience electric noise caused >by the USB to MIDI DIN cable, just jitter. My RME PCIe card has got >break through MIDI DIN. I don't know if inside the connector or on the >board are opto-couplers, but there are no noise issues caused by MIDI >connections and there are no level issues. > >Discounter keyboards don't provide MIDI DIN connectors anymore, they >provide USB MIDI onl -- http://www.grundgesetz-gratis.de/ _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user