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</o:shapelayout></xml><![endif]--></head><body lang=FR-CA link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><p class=MsoNormal><span style='mso-fareast-language:EN-US'>To answer some questions :<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><i><span style='color:#558ED5;mso-fareast-language:EN-US'>….. </span><span style='color:#558ED5'>With so many power sources, you may be hearing a ground loop. Never assume that the common return of multiple power sources are all the same potential.</span><o:p></o:p></i></b></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>There are no ground loops in my pedal board. Unselecting the Wha makes the 60hz hum completely go away.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>And placing the inductor in a specific way in the Wha metal box almost kill completely the hum.. so no ground loop for sure.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><i><span style='color:#558ED5;mso-fareast-language:EN-US'>….. </span><span style='color:#558ED5'>I'd start by looking at some of the *other* pedals to see how many could be converted to standard 9V centre-negative, and then reduce the number of transformers to reduce the noise.</span><o:p></o:p></i></b></p><p class=MsoNormal>> 4 of these pedals are powered with there separate AC supplies (9VAC, 9VAC, 7.5VAC & 22VAC).<br>> The other pedals are powered using 9VDC standard BOSS supplies<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='color:red;mso-fareast-language:EN-US'>The 4 x AC powered pedals :<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='color:red;mso-fareast-language:EN-US'>2 x LINE6 modelers that could be run using 6VDC supplies (they can run on 4 x 1.5vdc C cells) eliminating two transformers..<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='color:red;mso-fareast-language:EN-US'>1 x Blackstar DS2 powered by 16VAC (no possible DC powering):<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='mso-fareast-language:EN-US'><img width=523 height=145 style='width:5.4479in;height:1.5104in' id="Image_x0020_1" src="cid:image001.png@01DABE49.0CAAEF70"></span></b><b><span style='color:red;mso-fareast-language:EN-US'><o:p></o:p></span></b></p><p class=MsoNormal><b><span style='color:red;mso-fareast-language:EN-US'>1 x Electro Harmonix Hum Debugger pedal powered by 7.5VAC (no schematic available)<o:p></o:p></span></b></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>The following pictures shows the real actual schematic of my Wha.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>It’s an Italian Jen Cry Baby with a FASEL branded inductor.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>The bottom picture shows what I’ve done to ‘place’ the inductor at the ‘sweet spot’ to get the less hum possible. Not bad..<br>But a shielded inductor could be fine (but expensives..) <o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>And again, this is not a ground loop problem..<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><img width=783 height=886 style='width:8.1562in;height:9.2291in' id="Image_x0020_3" src="cid:image004.jpg@01DABE49.0CAAEF70"></span><span style='mso-fareast-language:EN-US'><o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal><o:p> </o:p></p><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><p class=MsoNormal style='mso-margin-top-alt:5.0pt;margin-right:0cm;margin-bottom:12.0pt;margin-left:58.05pt'><br><br>On Jun 13, 2024, at 4:46 PM, Jean-Pierre Desrochers wrote:<br>> I have a guitar pedal board that uses 8 pedals.<br>> The first pedal (receiving the guitar) is a Jim Dunlop Cry Baby Wah-Wah.<br>> The following pedal is a switchable overdrive with high gain.<br>> Then the pedal chain goes on with 6 other pedals to a final tuner that drives a guitar amplifier. Ok.<br>> 4 of these pedals are powered with there separate AC supplies (9VAC, 9VAC, 7.5VAC & 22VAC).<br>> The other pedals are powered using 9VDC standard BOSS supplies.<br>> Here is my problem :<br>> Since the Wah-Wah is connected at the ‘head’ of the pedal chain and uses an internal 500mH inductor in its circuit<br>> it acts like the secondary of a transformer picking up 60Hz<br>> from all the nearby transformers of the board.<br>> I had to unsolder the inductor from the inside PCB and,<br>> using short lenghts of wires connected to it … place it in the Wah-Wah housing<br>> at a ‘specific’ place and angle to get the less 60Hz pickup.<br>> This is annoying.. <br>> Now I can play with a little back ground hum when the Wah-Wah is activated..<br>> I was wondering if I could use an active inductor simulator circuit<br>> In place of the 500mH passive inductor.. (??)<br>> Feasable ??<br><br><br><o:p></o:p></p></blockquote></div></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>