Universal Audio 2192, Руководство пользователя

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The Technical Stuff
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bias points and signal levels of our all discrete, Class-A op-amp analog circuitry to provide the perfect
transition from pristine nominal levels to hard-driven high levels so the 2192 still produces musical results
before digital clipping occurs. Leaving the signal pristine until harsh clipping occurs introduces aliasing
and isn’t the way audio gear is supposed to work. Artificially clipping it (because it’s going to happen
eventually) isn’t any better because it eats into your headroom. We decided instead to use the transition
region to maintain a musical sound while still minimizing aliasing. We calibrate the 2192 to provide 18dB
of headroom in the transition region from nominal to clipping, and gradually increase the harmonic bloom
and Class-A compression as the signal approaches digital clipping.
It is often necessary to synchronize to external clocks (especially in a multitrack environment), but
providing high quality clock synchronization and recovery is not trivial. Worse yet, the sound quality of
many converters is affected when they are synchronized to an external clock. Many converters work well
when they’re the clock master, but as soon as you sync them to an external clock (even when the clocks are
high quality reference), their conversion quality deteriorates. Of course, performance gets even worse when
the external clocks are of poor quality. We didn’t want the 2192’s conversion quality to be dependent on the
quality of any external clock sources, so we incorporated a master clock conditioning circuit to eliminate
jitter injection from external sources. Happily, this circuitry also produces the highest-quality internal
clock, and so the 2192 internal clock rivals the best standalone units.
Another feature of the 2192’s clock conditioner is its ability to sync to clocks that are multiples or
submultiples of the sampling clock. The 2192 detects the incoming clock frequency automatically, and
adjusts its internal precision clock to match that frequency. This allows the 2192 to perform analog to
digital conversion at 96kHz or 192kHz using an external 48kHz house sync, while simultaneously
generating a new master clock at the higher sampling rate that’s in phase with the house sync.
Last but not least, we added clock distribution to the 2192 feature set to expand its role as the center of
the digital studio. Clock quality is essential for maintaining analog conversion quality, so integrating the
master clock within the converter is an obvious approach; the 2192 has four dedicated BNC word clock
outputs.