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On the polarizing subject of negative feedback, Ayre boss Charles Hansen too pursues his own path by eschewing global loops to avoid their time delays whilst the AX-7e certainly benefits from embedded loops to linearize the behavior of active parts like transistors as is common for most such circuits. To compensate for the usually higher distortion figures of zero global feedback amplification, Ayre embraces fully symmetrical circuitry. "Such architectures benefit to a greater extent from the distortion cancellation of dual-differential layouts" claims Krauspenhaar. Even so they don’t lead to ultra low output impedance and hence lower damping factors. The AX-7e’s is about 280mΩ. That makes for a damping factor of 30 into an 8Ω speaker where feedback amps often reach figures of 10mΩ or better.

The CX-7e MP avoids global feedback as well and duplicates the dual-differential layout to sport both RCA and XLR outputs. Digital is limited to AES-/EBU symmetrical. Ayre claims the lowest jitter for this defeatable output. To sidestep NFB successfully and achieve complete symmetry, the DAC chip is a Burr Brown PCM1738 which, Krauspenhaar says, "is one of the few to not include an I/V conversion summing amp with its built-in global negative feedback" and "can supply the 180° counter-phase signals discretely". Sun Audio also retaliates with their own propaganda on damping factors. "Far senior to the subject of relevant limitations in speaker control is the copper resistance of voice coils and preceding filter parts. Those are as embedded in the speaker current loop as the amp’s output impedance… More important is that unlike practically all feedback amplifiers the AX-7e’s output impedance remains nearly constant across the full audible band."

The disc spinner runs a fully enclosed Teac drive said to be well shielded, quietly running and highly reliable. Like in the amp the EI core transformers are from US supplier Mercury. One transformer supplies the sled, control circuitry and display, the other D/A conversion and output stages.

A technical specialty which becomes a small voicing tool for the end user is the digital filter whose rear-mounted toggle affords two options of listen and measure modes. Ayre is very critical of the pre-ringing in conventional linear-phase filters since such behavior is wholly unnatural. Acoustic events in real life always have echoes follow, never precede them.

Cognizant of the demands of effective filtering, phase linearity and minimal pre- and post-ringing, the CX-7e MP’s measure mode is based on a minimum-phase filter (hence the MP suffix of the model name) with a slightly higher but as such less artificial post ringing. This trades for zero pre-ringing and some phase shift in the highest frequencies. Listening sessions had Charles Hansen convinced however that even more harmless post-ringing can lead to artificial brightness and unrest in the sonic picture. As per Krauspenhaar, "listen mode thus incurs a small treble depression but not only shuns all pre-ringing, it also limits post ringing to a single cycle rather than the four or five which standard filters are guilty of. Charles Hansen selected the filter frequency and slope such as to mostly also eliminate the ringing of the A/D converter’s FIR filter on the recording end to really make sense of the whole solution."