There are RMAA and like bs2b measurements of MEIER-AUDIO's CORDA ARIETTA headphone amplifier with crossfeed filter.
The frequency responses of crossfeed filter are made by frequency analysis of white noise: one channel signal is for frequency responses of lowpass and highboost filters, mono two channels signal and independent two channels signal is for approximate stereo frequency response.
Picture 1. Crossfeed filter frequency response.
The time delay response of crossfeed filter are made by analyse of one channel sinusoidal signal.
Picture 2. Crossfeed filter time delay response.
The measurements of an amplifier are made by RMAA software through SB Live 24 card. Click to see:
SB line out -> SB line in
SB line out -> ARIETTA -> SB line in
SB line out -> ARIETTA with 24 Ohm load -> SB line in