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Transfer functions for the proposed Serge and Lockhart (R L = 7.5 kΩ) wavefolder models. 

Transfer functions for the proposed Serge and Lockhart (R L = 7.5 kΩ) wavefolder models. 

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Article
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Wavefolders are a particular class of nonlinear waveshaping circuits, and a staple of the “West Coast” tradition of analog sound synthesis. In this paper, we present analyses of two popular wavefolding circuits—the Lockhart and Serge wavefolders—and show that they achieve a very similar audio effect. We digitally model the input–output relationship...

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Context 1
... factor accounts for the difference between physical parameters I s and η in each circuit. Figure 9 shows a comparison of the transfer functions for the Lockhart (R L = 7.5 kΩ) and Serge wavefolders implemented using the parameter values in Tables 2 and 4, respectively. From this figure, we can observe that the only significant difference between both transfer functions is in their sharpness at the folding points. ...
Context 2
... although the Lockhart wavefolder was originally designed to operate as a standalone unit, it can be adapted into a series topology with relative ease. Here, we propose using the wavefolding structure shown in Figure 19 to expand the synthesis capabilities of the Lockhart wavefolder. This design, while not based on any existing circuit, is comparable to that of the Yusynth Metalizer which also utilizes four Lockhart circuits in series [55]. ...
Context 3
... blocks labeled "LWF" in Figure 19 correspond to the proposed Lockhart wavefolder model. In order for this cascade of Lockhart wavefolders to behave as expected, we need to make sure that the individual folding stages satisfy two criteria. ...

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