If you haven't read my inaugural Kinki review of the EX-M1 integrated which includes a brief factory tour, the key intel relevant also for today's monos is designer Liu's favoured output device: Exicon's lateral Mosfet. As Ivo LinnenberG says about them, "they sound so incredibly fine because they're so ridiculously fast and linear. Very low and particularly linear capacitance between drain, source and gate is the main reason. With most if not all other Mosfets, this capacitance which is unavoidable in any semiconductor is extremely voltage dependent. That introduces much unwanted distortion especially at high frequencies."
The transistors mount to a solid copper wedge that's inset into the front panel.
Exicons show up in amps from Bakoon, Crayon, Goldmund, LinnenberG and Nagra. That covers a swath of personal favourites. Like most of them, the EX-B7 are wide bandwidth DC-coupled. Eliminating coupling capacitors tends to remove colouration. Bandwidth well in excess of x 10 the audible range eliminates phase shift in the 20Hz-20kHz extremes. That benefits pitch definition in the bass, clarity in the treble and overall speed. As a concept, it differs from capacitor/transformer-coupled valve amps whose treble may begin its roll-off at already 20kHz. They will sound slower and softer by contrast. That's not a value judgment. It's just a distinction on flavour or gestalt-. Now personal taste and suitability with surrounding hardware become the deciders. Fundamentally you'd not expect such designs to sound alike. However, as the EX-M1 had previewed already—and as Nagra's Classic Amp and LinnenberG's Widor would confirm—the 'fast amp' concept allows for sufficient voicing leeway to inject some warmth of the other school. As Liu put it, "our EX series products focus on delicate and transparent sound with cleanliness, clarity and a tad of warm smoothness which is relatively flattering to listen to." It's his Vision range that's "tuned for high definition, high dynamic range and ultimate sound reproduction which corresponds to the term vision."
The twin power transformers mount upright beneath the motherboard. The narrow slot above the black cross brace affords the best and only glance at them.
With their EX prefix, the B7 monos pledge allegiance to the M1 sound. With twice the number of Mosfets under the hood and beefier power supplies, one would simply expect the usual 'bigger amp' benefits from otherwise similar circuits: higher density, more powerful bass, larger dynamics, greater low-impedance headroom. WIth the EX-M1 integrated still on hand from its review, a direct A/B would investigate these exact aspects. Of course the monos require addition of a standalone preamp. The integrated integrates it. To keep things in the family, Alvin dispatched Kinki Studio's matching fully balanced EX-P7 linestage.
To show off the ebullient internal construction, I asked Liu for a photo straight off his assembly bench.
At its tag of $2'198 Singaporean (~€1'400 at time of writing), that brought the pre/monos in at a click below €3K versus €1'840 for the integrated. For connectivity, the EX-P7 actually omits one of the M1's RCA inputs but then adds 2:1 RCA:XLR outputs. Cosmetics overlap as do remote, display and R2R volume across 256 values in 0.25dB steps. As to natural-born competitors for the EX-B7, my most obvious choice in our hardware library were LinnenberG's Liszt monos. With equal power, their own quartet of Exicon laterals and similar sizing, the major offsets were German manufacture, dealer network sales and a concomitant €8'500/pr sticker. At more than thrice the Kinkis' ask, it predicted a time of reckoning once the EX-B7 landed on our Irish soil.
In the meantime, Warsaw colleague Dawid Gryzb had reviewed then acquired the EX-M1 integrated for his HifiKnights.com site. Kinki Studio were on a roll and victory lap.
Transit from Guangzhou to Westport was rapid. It took just two days to pass through six DHL facilities and across five international borders. At least one day was saved when DHL decided to put their 3-box consignment on the delivery truck at 8:00, then call me three hours later with the VAT amount to be settled byphone before the driver arrived in the afternoon. Traditionally they collect coins first, then load the truck the day after. Wherein lies the usual small print raising its ink whenever one mail-orders across separate trade zones. We're liable for customs clearance and value-added tax. In the EU, the latter will be +20% of the value declared. Be sure to factor on that upfront so the COD demand won't set you off. The monos arrived each in their own carton, double-boxed and cradled in massive hard foam caps. The emerging silvery blocks were rather bigger than expected; clearly larger and heavier than the German Liszt. Packing them separately kept not only the lower backs of the freight companies happy. This was serious hardware; again.
