The output signal of a charge sensitive preamplifier or shaping amplifier typically passes through at least one AC-coupled amplification stage in order to block a DC bias. The result is that the overall DC gain of the electronics is zero, meaning that the time-averaged output value of the shaping amplifier is zero. This presents a problem when a shaping amplifier processes pulses at high rates, because the signal baseline may become significantly depressed. This may also result in a shifting baseline, one that is dependent on the counting rate, and this can degrade the resolution of spectroscopic measurements.