Full Product Description
Frequency Response Measurement & Correction
The Phi TC can sound a bit muddy in the lower midrange between 300 and 400 Hz. The broad midrange rise in frequency response, peaking to +4 dB at 1.1 kHz gives the headphone a nasally tonal quality pushing vocals too far forward in the mix. The -2 dB dip at 2 kHz, which is in the ears most sensitive range takes away the natural edge on vocals and instruments.
Engaging the high-resolution FIR filter optimizes the Phi TC’s to sound perfect with a rule flat +- 0.5 dB frequency response. The lower midrange resonance is gone and vocals and instruments in the critical midrange now sound natural. The imaging is also improved especially the depth of field where the vocals and lead instruments now sound balanced in the overall mix.
Audiophile Style article including listening impressions and detailed measurements: “Taking The Abyss AB1266 Φ TC Headphones To Another Level”