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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I would certainly investigate the power first. I had some interesting noises / zaps from older gear (in particular) when they were powered from two different circuits. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>First, unplug both racks and confirm voltage / neutral / ground on your two receptacles<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Next, I’d measure voltage from hot-to-hot, neutral-to-neutral and ground-to-ground on the two receptacles. Be aware you could have a 240V differential, so set your meter accordingly.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Next, disconnect the audio cable, power up both racks. Measure voltage chassis-to-chassis between both racks, then audio ground-to-audio ground on both racks<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>After that, run all that gear from one outlet and see if plays nicely<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That should help diagnose where the problem actually lies<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dave Magnuson<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Synth-diy [mailto:synth-diy-bounces@dropmix.xs4all.nl] <b>On Behalf Of </b>Jim Blair<br><b>Sent:</b> Monday, March 14, 2016 4:03 PM<br><b>To:</b> synth-diy@dropmix.xs4all.nl<br><b>Subject:</b> [sdiy] Prophet 5 weirdness.<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Hi all. Thanks in advance for your help!<o:p></o:p></span></p><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>I have a Prophet 5 rev 3.3, which someone in the distant past converted into a brain-only format. So, no keyboard. Midi only. It's now happily residing in the lower row of a modular. It works great, and sounds amazing. The PSU has been recapped, and new regulators installed. All is well.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Almost.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Get this. When I plug the audio out into a guitar amp or a pedal, the synth works great. But when I plug it into my API preamp, or Sansamp rack unit, the synth loses it's mind. All the front panel lights start flickering, and the output is all loud and nasty noises.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>I think that the Sansamp and API are both plugged into a different AC house-circuit than the P5, but I'm not sure of this yet. More investigation is required. I run other synths, both modern and vintage, into the Sansamp and API all day long, and have never experienced a problem. <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Thoughts?<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:black'>Jim<o:p></o:p></span></p></div></div></div></body></html>