Achieving a high quality ultra-treble has been a challenge in the IEM industry. BA drivers are compact, but offer low ultra-treble extension, and are also limited by their output and timbre quality. EST drivers are difficult to utilize in multi-driver setups as they have very low output, often being masked by other driversโ volumes. Additionally, EST drivers can sound very metallic at high voltage, resulting in an unnatural presence. For this reason, Kiwi Ears has developed a new ultra-treble tweeter with a small modular size of only 5mm, but a tremendous output of 118dB. The Kiwi Ears MPT driver is efficient at producing sustained treble frequencies from 4kHz to 40kHz.
Typical BA or EST drivers have diminishing treble output after 8kHz.
However, the MPT driver can maintain the same constant sound pressure at
14kHz as at 4 or 8kHz. This allows extreme flexibility in tuning the
MPT driver to match other driver types such as BA or DD, as their
outputs are similar. Furthermore, the MPT driver has a significantly
more natural tonal texture than EST or BA drivers, achieving better
integration in the mix.
A balanced sound signature is a core belief at Kiwi Ears. The Quintet took almost a year in development due to the engineering difficulty of combining all of its driver types. However, the result is a completely balanced tone that accurately reflects the best qualities of each driver. The sub-bass hits strong and fast, with a 9dB shelf that transitions into a flat mids at 300Hz. This mids-bass transition ensures that there is a slight warmth in the lower mids for bass guitar notes to be in the mix, but still retain a studio-monitor-like neutrality to the upper mids.
This creates a natural and clean tone without any muddying or bloating. The treble accurately peaks at 3kHz to match the acoustic perception of the human earโs pinna, with a gradual decay into the upper treble. Thus, the treble is well-detailed and sparkles, but without any shrillness or harshness. The planar and PZT drivers provides a good extension into the treble until 40kHz, making a higher sense of resolution, airy atmosphere, and soundstage.