What does the “DC” designation on some components mean?
The “DC” designation refers to the fact that this preamp, amplifier or integrated amplifier can amplify signals over a much wider range than non-DC designs. Here is why that is useful: The sounds that most people can hear from their stereo are created by speaker surfaces that are being forced to move back and forth by precisely controlled positive and negative surges of current driven through them by the audio amplifier. This occurs at rates of from twenty times a second, to as high as twenty thousand times a second. For the slowest rates (20 times a second), the amplifier has to correctly amplify these slow signals; if it does not, the sound that comes out of the speaker will be different than the sound on the audio source. Many amplifiers do a fairly poor job of amplifying such slow signal changes – they are designed to cover a wide range of signals, but at the edges of that design, the amplifier’s performance limitations begin to affect the signal adversely. The reason that designs
