| Sonically the player’s strengths lie in its ability to
deliver realistic high frequencies, very good timing with excellent low level
resolution. Hook up the Opus 21 CD player and you are greeted with a highly
detailed sound with excellent clarity. Instruments and vocals cleanly defined,
image focus is superb and stereo separation is very good. At £3000.00 the
design of the Opus 21 is well executed and is clearly the work on a designer
who is striving for the best performance at and above its market value. Are there
any complaints? Aside from the flimsy plastic CD tray, annoying ergonomics
which prevent you from accessing the front panel controls with the CD drawer
open; it is very neat and easy to use. Its music making abilities are not free of
criticism, but on balance you will find tradeoffs with other players at this
price point, a case of whether you prefer ‘apples or oranges’. For example, the Naim Audio CDX2 will deliver
better dynamics; superior bass grunt with more rhythmic timing but cannot
manage the same high frequency skills of the Opus 21. What the Opus 21 does
well it does ‘very well’ but there are gripes. While the frequency balance
seems even and balanced, sound lacks a certain "weight" and authority.
While treble extends way up, the quality of treble remains light and not very
solid, feathery almost. This problem also extends to the midrange and while
there is no gross inaccuracy one can point too it does lack texture, sheer
“volume” in vocal range. It is not up with the best in speed and timing,
preferring to play safer when dynamics and attack are called for.
Having spent considerable time listening to the Opus 21
we embarked on improving the performance of the main CD player unit and power
supply unit with a series of upgrades. The upgrades focus on improving main
power supplies, improving regulated DC supplies, lowering clock jitter, control
of resonances. These upgrades work with the design and remove system weaknesses
allowing the player to reach its full potential. The upgrades span across
levels 1 & 2 with level-1 getting to grips with the most prevalent issues, while
level-2 is a more comprehensive upgrade to achieve reference performance. The
level-1 upgrade commences with upgrades to the power supply unit, here main
power supply reservoir capacitors for the audio circuits are upgraded to
premium types with increased capacitance for improved ripple rejection. The
general purpose capacitors for input and output bypass for the DC regulation
are upgraded to premium types, lowering the system noise floor. Significant
chassis and mechanism damping is completed. This is a comprehensive damping
package designed to deal with internal vibration and resonance. A pair of Bybee
Large Quantum purifiers is installed for the AC input supply line. The Bybee
Purifiers by remove Quantum noise, in this case the dominating noise is
frequency dependent which behaves like the musical spectrum, and often referred
to as 1/f noise. This noise envelope mimics that of the musical signal and blends
in very well with the music. Once buried within the music, it 1/f noise defuses
image outlines and adulterates harmonic textures. When Bybee purifiers are
installed this 1/f noise is removed to varying levels allowing you to hear the
music unhindered. In the AC line we hear less graininess, improved bass &
dynamics. Next our attention turns to the CD player’s ‘master clock’ is ideally
located very close to the 4x PCM1704J DAC’s. The quality of clock is an industry
standard Pierce type; a single inverter, two resistors, two capacitors, and the
quartz crystal which acts as a highly selective filter element for the given
frequency. This type of clock is low cost since it requires minimum components,
it is also very easy to implement but does not have very low phase noise and high
power supply noise rejection which means higher jitter. We replace the Pierce
oscillator with a Superclock 4, this “Superclock” generates and extremely low
jitter output and vastly improves all areas of performance.
More to come…
Resolution
Audio Opus 21 Upgrades
■ Superclock 4-S Ultra-low jitter master clock.
■ Bybee Large Quantum Purifiers for AC input.
■ Panasonic FC audio capacitors for digital & analogue power supply.
■ Panasonic FC audio capacitors for regulation bypassing.
■ Bybee Slipstream Purifiers for DC supply lines.
■ Black Gate NX Hi-Q capacitors for PCM1704J decoupling.
■ Black Gate FK capacitors for I/V conversion decoupling.
■ Vishay TX2575 Naked
Foil resistors.
■ Bybee Slipstream signal output (RCA only).
■ Deep Cryogenic Treatment (DCT) for power supply unit.
This modification has been discontinued.
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