Quote from Mr. Mazmoto (one of the engineers that worked on the MZ-RH1):
Apparently, the current digital music player’s the best feature must be that of usability. Among all best points, the product planer’s chosen path was, not relying on the sound effect or the sound processing, but the rebirth of the original sound recorded. The approach of doubling the capacity of the Coupling Condenser was born from this need.
The Coupling Condenser is an audio component which is being used in the last process of amplification to cut the direct current, to prevent any potential damage to a headphone or a pair of speakers. Increasing the capacity to preserve the unique low frequency sound is a known method used from the days of an analog amplifier.
“There is a technical reason to why a coupling condenser was not footed on a portable audio device. As the portable device is very limited in its space dimension, having a big enough coupling condenser to deliver enough power is not realistically possible. There has been a serious talk of enhancing this area, as soon as the first generation MZ-NH1 was completed. Since then, we were in talks with multiple suppliers of a coupling condenser, to repetitively request them of the size requirements, so we were able to meet the size requirements, without missing the delivery date.” (Mr. Mazmoto).
