From Michael E Caloroso Sent Thu, Dec 27th 2018, 02:33
From Michael E Caloroso Sent Thu, Dec 27th 2018, 02:33
I was not happy with MMA approving 1/8" interconnects at all either. Then I uncover my grounding error and can only imagine the headaches introduced by 1/8" interconnects. 1/8" interconnects rank up with RCA as the worse interconnects every made and are banned from my system. Yes there are piles of modular using 1/8" interconnect. They'll work today, not likely in the future. I usually buy parts from Mouser/Digikey. When my Mac computer comes back from the repair shop, I'll retrieve OEM/PN from the soft copy receipts that are stored on that machine. MC On 12/26/18, Brian Willoughby <xxxxxx@xxxxxxxxxxxx.xxx> wrote: > Wow! > > I=E2=80=99m very disappointed that the MMA approved 1/8=E2=80=9D TRS jack= s for MIDI on small > devices, for the very reason that it=E2=80=99s common to connect the Slee= ve of a > jack to the metal of an enclosure or modular face plate. Granted, some > people have pointed out that it=E2=80=99s possible to carefully select 1/= 8=E2=80=9D TRS > jacks where this grounding is prevented and/or to manually install > insulating grommets and nuts, but that sounds like a headache waiting to > happen. > > For my MIDI builds, I use jacks that are plastic, and which screw to the > enclosure or face plate without any possibility for ground connections. W= hat > manufacturer and part number have you been using for MIDI jacks? I=E2=80= =99d always > assumed that it=E2=80=99s easier to find non-grounded DIN-3 jacks. > > Brian Willoughby > > > On Dec 26, 2018, at 6:04 PM, Michael E Caloroso <xxx.xxxxxxxxxxx@xxxxx.xx= m> > wrote: >> While we're discussing studio MIDI wiring... >> >> ...I build my own I/O panels for my racks, and my own MIDI cables. I >> recently uncovered a nasty bug that has perplexed me for years: >> >> If you use metal shell MIDI plugs on your DIY MIDI cables, DO NOT >> ALLOW MIDI GROUND TO COME IN CONTACT WITH THE SHELL. >> >> I was gigging my road system and was experiencing intermittent MIDI >> errors. After finally being able to reproduce it at home, I figured >> out that the metal shell of the MIDI plug shorted to earth ground via >> the metal DIN jacks I was using on my DIY I/O panels. Stray shield >> wires from the cable had contacted the cable clamp of the plug >> (despite my best attempts at trimming the stray wires), completing the >> short circuit of MIDI ground to earth ground. MIDI gets very upset >> under this condition. >> >> I use an EBTech cable tested after I build all my DIY cables, and it >> does not have the capacity to detect a short from the shell to any of >> the pins - it's not supposed to. Even with my diligent testing after >> completing a cable, this bug had eluded me for YEARS in my studio >> system. Yes I was well aware that the MIDI specification grounding >> system is designed that way FOR A REASON. >> >> The only way to guarantee complete isolation of MIDI ground from earth >> on the metal shell of the plug was to disassemble the plug and add >> shrink tubing over the trimmed end of the cable. This separates any >> stray shield wires from the metal clamp of the plug. Once I fixed my >> cabling for the stage rig, it behaved MUCH better. >> >> Nasty bug, this. >> >> For years I had wondered why my SYSEX dumps were never 100% reliable, >> now I know why. >> >> That's just the STAGE rig. Now I have to make the cable corrections >> to my STUDIO system, which has easily over 30 DIY cables that I built. >> Guess how I am spending my holiday break... >> >> Sent from my iGroundingCanBiteYou, >> MC >> >