Proposed in this paper, multicomponent signals represent a new versatile tool for description of single- and multicarrier signals with amplitude-phase shift keying (APSK). Each component carries a sequence of symbols, which have increased symbol transmission time. Neighboring pulses do not overlap inside the component; hence, each component has zero inter symbol interference (ISI). The value of peak to average power ratio (PAPR) and the ISI measure are accurately calculated for the assembled multicomponent signal, which is represented as the sum of components. We demonstrated the pulse shape optimization to provide a narrow spectrum of single-carrier multicomponent signal with the PAPR value and the ISI measure included as additional constraints. By minimization of the occupied bandwidth for the fixed energy concentration, we achieved a comparable efficiency for the multicomponent signals with QPSK as for conventional orthogonal signals with QPSK, 16-QAM or 64-QAM. Moreover, proposed optimal multicomponent signals clearly outperform in terms of modified energy consumptions, which include a signal PAPR value into account.