No . Moog ' s Transistor Ladder Filter was just mimicked by Roland by making a Diode Ladder Filter since a diode can act the same as a transistor . The comparison to the well known alternative acid sound , SH 101 , was more about how maybe something less physically similar could produce something more audibly similar since small changes architecturally can produce wildly different results , especially since the Jupiter , JX , Juno , and 101 all use the same chip but the circuitry around them make for the 101 being very acid , the Juno being somewhat acid , and the JX and Jupiter being very snarly . But obviously both Mother demos on the page today make the case that Moog filters make for good 303 imitations , which I hadn ' t ever seen before . And it ' s better they ' re not the same ! The more types of acid filters , the better ! DIf you ' re interested , I ' ve been trying to read up on circuitry design . Here was a pretty good article . diode