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</o:shapelayout></xml><![endif]--></head><body lang=FR-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><o:p> </o:p></p><p class=MsoPlainText><span lang=EN-CA>I think the following question has been answered somewhere<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>In this forum but anyway..<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA>In 2014 I built some Moog 904A clones for my modular<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>and so far have been happy with them.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>I copied the exact Moog 904A schematic and reverse engineered<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>the pcb layout to fit my front panel needs.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA><a href="http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/Module_pictures/M104A_VCLPF_front.JPG">http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/Module_pictures/M104A_VCLPF_front.JPG</a><o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><a href="http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/Specifications/M104A_VCLPF_schematic.pdf">http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/Specifications/M104A_VCLPF_schematic.pdf</a><o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><a href="http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/Module_pictures/M104A_VCLPF_assembled_back.JPG">http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/Module_pictures/M104A_VCLPF_assembled_back.JPG</a><o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA>For the low pass ladder caps I used Vishay film capacitors.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>0.075uf, 0.33uf and 1.2uf @ 10%.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Differently from Moog's choice these Vishay caps have the exact uf values.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Looking at some vintage Moog 904A VCF I found that over time<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>the factory did not always put the same type of caps<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>in their VCF.. Mostly orange drops but not always. <o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>And because orange drop caps didn't have and still don't have 0.075 and 1.2uf values<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Moog used parallel caps to get these values.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Enough talk about Moog's preferences.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText><span lang=EN-CA>My question is:<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Would it make any differences in my 904A vcf sounding<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>if I'd replace all the Vishay film with orange drop caps ??<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>I found that for instance many fine guitar amps<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>decided to use orange drop caps over any other types..<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Doing so I will have to do what Moog did and parallel<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>caps to get 0.075 and 1.2uf values.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>That will give a 'funky' looking to my pcb tough.<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>Vishay's caps fitted right on my pcb, but orange drop caps could be<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA>a nice 'sounding' replacement.. <u>or it does not worth it..</u> ??<o:p></o:p></span></p><p class=MsoPlainText><span lang=EN-CA><o:p> </o:p></span></p><p class=MsoPlainText>What do you think ?<o:p></o:p></p></div></body></html>