HEDD allows you to add tube-like characteristics to your digital audio with two knobs, specifically pentode and triode. A separate knob for each tube type is available at the flip of a switch! TRIODE The triode function creates a triode like harmonic structure. This affects the bottom of your signal by fattening it up. This function contains strong even order harmonics. It should be noted that even order harmonics may or may not be easy to hear depending on the program and how much you are adding. This function is not strictly even order harmonics. The harmonic structure changes with signal level and the amount of process being applied, just like it does in a tube and the analog world. PENTODE The pentode function creates mostly third harmonic information but contains some even order harmonics and some higher order odd harmonics depending on the signal level and the amount of process. This is like driving a pentode into over load in a controlled manner. The pentode process makes things sound brighter, brings out detail, and also affects the triode process because the two processes are in series. There is also a compression effect that takes place if you run the process at higher settings. TAPE The tape function emulates magnetic recording tape. Recording tape distortions are odd harmonic, starting with the third and fifth. As you increase the level on tape the harmonic content increases and higher odd harmonics are added. With a tape recorder there are record and reproduce EQ circuits that modify the harmonic content. The result is a sound that fattens up the bottom and midrange of a recording and as you increase the process there is a loss of hi frequencies with respect to low frequencies. This is a result of the compression function and eq. curves in the process. The compression also squashes peaks and results in a higher average level.

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