EX-M7

Reviewer: Srajan Ebaen
Financial interests: click here
Main system: Sources: Retina 5K 27" iMac late 2020 with Ventura 13.4, 40GB RAM, Audirvana Studio, Qobuz Sublime, Singxer SU-6 USB bridge, LHY Audio SW-6 & SW-8 network switches, Cen.Grand DSDAC 1.0 Deluxe; Active filter: Lifesaver Audio Gradient Box at 100Hz/4th-order hi/lo-pass; Power amplifiers: Kinki Studio EX-B7 monos & EX-M7 stereo; Headamp: Cen.Grand Silver Fox; Phones: HifiMan Susvara; Loudspeakers: Qualio Audio IQ w. sound|kaos DSUB 15 on Vibra 68 footers, Audio Physic Codex, Cube Audio Nenuphar Cables: Complete loom of Kinki Studio Earth; Power delivery: Vibex Granada/Alhambra on all source components, Vibex One 11R on amps, Furutech DPS-4.1 between wall and conditioners; Equipment rack: Artesanía Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands; Sundry accessories: Acoustic System resonators, LessLoss Firewall for loudspeakers, Furutech NCF Signal Boosters; Room: 6 x 8m with open door behind listening seat
2nd system: Source: Shanling M3 Ultra, Soundaware D300Ref; DAC: Sonnet Pasithea; Preamp/filter: Lifesaver Audio Gradient Box at 60Hz/4th-order hi/lo-pass; Amplifier: Crayon Audio CFA-1.2 Loudspeakers: MonAcoustic SuperMon Mini, Dynaudio S18 sub on sound|kaos Vibra 68 footers; Power delivery: Furutech GTO 2D NCF + Akiko Audio Corelli; Equipment rack: Hifistay Mythology Transform X-Frame [on extended loan]; Sundry accessories: Audioquest Fog Lifters; Furutech NFC Clear Lines; Room: ~3.5 x 8m
Desktop system: Source: HP Z230 work station Win10/64; USB bridge: Singxer SU-2; Headamp/DAC: iFi iDSD Pro Signature; Masterclock: LHY OCK-2; Headphones: Final D-8000; Headfi/speaker amp: Enleum AMP-23R; Loudspeakers: EnigmAcoustics Mythology M1
Upstairs headfi/speaker system: Source: smsl Dp5 transport; DAC: Auralic Vega; Integrated amplifier: Schiit Jotunheim R; Phones: Raal-Requisite SR1a
2-channel video system: Source: Oppo BDP-105; All-in-One: Gold Note IS-1000 Deluxe; Loudspeakers: Zu Soul VI; Subwoofer: Zu Submission; Power delivery: Furutech eTP-8, Room: ~6x4m
Review component retail: $2'798

Selectable DC filter on/off, floating ground plus ground and earth posts.

Equal opportunity. It's a cornerstone of modern thinking that's unrealistic so non-achievable. People are uniquely individual. So is their upbringing. Once we factor past lives, the notion of a tabula-rasa birth expires. Our life doesn't begin as a blank diary which we write our story in. Though the book of our life contains many blank pages to be filled, the first few chapters are already written. Those create the general setup. They predetermine our life's plot line and general arc. It's karma from before. We bring in subconscious memories by way of unprocessed past traumas, general tendencies, unfulfilled desires, lessons to master, things to experience. Next add genetic imprints shaping our DNA; plus nine months of shared blood chemistry with our mom and being wet-wired to her thoughts and emotions. This isn't a virgin white slate or ground zero. This is a pre-cast and weighted script. Even were equal opportunity relative to education and job choice achievable, what any individual can and actually wants to do about it diverges wildly. In those terms, equal opportunity doesn't exist.

That said, is equal opportunity achievable in hifi; not for people but frequencies?

With the vast majority of speakers being box variants, their dispersion narrows with ascending frequencies. Below ~200Hz it begins to become omnidirectional. Wavelengths get long enough to wrap around front baffles rather than only fire forward. Our room dominates. The upshot is ever more reflected sound at lower frequencies against ever more direct sound at higher frequencies. On that score reality conspires against equal opportunity for freqs. This basic observation was at the root of my dive into active adjustable bass of cardioid so directional dispersion. It has the low frequencies radiate less dissimilar from the higher ones. Rather than cause grave textural discontinuity—bloomy and reverberant down low, ever more crisp and articulate higher up—the transition gets less severe for improved textural linearity or time-domain continuity.

Since my favored Ripol sub from sound|kaos is passive, it needs external amplification and filtering. So I was free to pick my bass amp. The great majority of active subs relies on class D for its extreme power density and low-heat operation. Cool and small are two great advantages inside a speaker enclosure. Having high-power high-feedback class D amps from Purifi and Nord on hand, I didn't fancy them. I heard a different type of textural seam against the bands which Kinki Studio's EX-B7 monos cover in class AB, coupled direct to avoid signal-path capacitors and with extreme bandwidth. My choice of external sub amp became Goldmund's Job 225, a conceptually very similar design. A Lifesaver Audio Gradient Box smart active analog xover sits at 100Hz/4th-order. That extends directional bass across more than two octaves to seriously undermine two room modes without unsightly acoustic treatments.

Kinki Earth cables, Børresen X3 speaker loaners.

By mid September, the always chill 10-year old Job 225 began to run super hot. Impending end of life from a runaway transistor? The time had come to recast my bass amp. Taking auditions was Kinki Studio's EX-M1 integrated, a sonically ideal match. Its much lower input sensitivity simply meant a lot of gain compensation. I also disliked the non-extinguishable CH1 255 display showing input and an extra volume control set to max. Next to audition was a class A Pass Labs XA30.8. Whilst its voltage gain needed far less compensation, its harmonic and textural profile wasn't right. Compared to the continuous Job 225, the bass now was fatter and warmer. My overall sonic profile had gotten subtly pear-shaped not on amplitude but tone texture.