D/A conversion requires interpolation to reconstruct the analog signal from its digital samples. This reconstruction process can be expressed as a linear combination of shifted pulses. The pulse shape will affect the quality of the reconstruction, as will the relative sampling rate. When the signal is oversampled, interpolation is much easier and the reconstructed analog signal closely matches its original form. The nine movies below illustrate the varying quality of the reconstruction with different pulse shapes and different sampling rates.

Square Pulse	Three movies that illustrate reconstruction at various sampling rates via the square pulse: at one, two and four times the Nyquist rate.
Triangular Pulse	Three movies that illustrate reconstruction at various sampling rates via the triangular pulse: at one, two and four times the Nyquist rate.
Truncated Ideal Pulse	Three movies that illustrate reconstruction at various sampling rates via the truncated ideal pulse: at one, two and four times the Nyquist rate.