A conceptually simpler implementation of oscillators is based on wavetables. These require frequent access to the memory and accurate interpolation. The waveshape can be morphed by mixing different wavetables, and a lot of great digital synthesizers from the 1990s on used this technique. More generally, any electronic circuit can now be transposed to the digital domain thanks to the advances in the field. One approach for solving the differential equation of a circuit is the wave method, also known as the wave-digital method. The classic digital audio effects reference by Udo Zolzer covers all sorts of effects, while another book by Will Pirkle explains how to implement them in C++. Three detailed papers from Jon Dattorro covering reverberation, filtering, modulation effects, and pseudo-noise generation that may be interesting to the reader can also be found.