Micromega CD 20 MM CD20SILVER User Manual
Product codes
MM CD20SILVER
The analog stages
Bearing in mind what has been previously discussed, the differentiating stages had to be as equally
efficient as the other component’s performances. The choice was difficult because, as specialists know
well, measurements and listening do not always go hand in hand; there is always an empirical part
which remains and experience in the audio field is thus essential. Although SMD components are often
rejected by the most extreme purists, once again experience proved that it is not as simple as that. You
have to be wary of taking shortcuts as they often turn out to be very limiting. Each technology has its
advantages and disadvantages, but it is clear that when working with signals of very low amplitude, the
simplest way is often the best and SMD components do allow a substantial saving in space, which in
our case is essential. Finally, the type of alignment of the analog output filters was not left to chance
and the choice of a third-order Bessel filter turned out to produce the best results. The frequency cut-off
was placed at 75 kHz, well beyond the audio band guaranteeing a perfectly linear phase from 20 Hz to
20 kHz and a constant group delay on the full audio band. For the last pole of this alignment, we
deliberately selected a passive element in series with the signal in order to reject all high frequency
residues which could have slipped through even the tightest of nets. The output signal is free from any
DC component due to the use of a specific circuit, which allows a low impedance connection without
resorting to a coupling capacitor. Very often this capacitor has to be electrolytic in order to eliminate low
load impedance which is characteristic of certain amplifier inputs. Finally, a high-speed circuit which
detects presence or absence of AC power supply sends the signal to the CD20 to emit DC bursts when
switched on or in the event of sudden mains cut off.
efficient as the other component’s performances. The choice was difficult because, as specialists know
well, measurements and listening do not always go hand in hand; there is always an empirical part
which remains and experience in the audio field is thus essential. Although SMD components are often
rejected by the most extreme purists, once again experience proved that it is not as simple as that. You
have to be wary of taking shortcuts as they often turn out to be very limiting. Each technology has its
advantages and disadvantages, but it is clear that when working with signals of very low amplitude, the
simplest way is often the best and SMD components do allow a substantial saving in space, which in
our case is essential. Finally, the type of alignment of the analog output filters was not left to chance
and the choice of a third-order Bessel filter turned out to produce the best results. The frequency cut-off
was placed at 75 kHz, well beyond the audio band guaranteeing a perfectly linear phase from 20 Hz to
20 kHz and a constant group delay on the full audio band. For the last pole of this alignment, we
deliberately selected a passive element in series with the signal in order to reject all high frequency
residues which could have slipped through even the tightest of nets. The output signal is free from any
DC component due to the use of a specific circuit, which allows a low impedance connection without
resorting to a coupling capacitor. Very often this capacitor has to be electrolytic in order to eliminate low
load impedance which is characteristic of certain amplifier inputs. Finally, a high-speed circuit which
detects presence or absence of AC power supply sends the signal to the CD20 to emit DC bursts when
switched on or in the event of sudden mains cut off.
Conclusion: A challenge achieved
To produce a CD player at a reasonable price is not easy when your aim is to achieve the highest level
of musical reproduction, which is as faithful and transparent as possible. CD20 reaches that point
admirably and the thousands of owners of this model are only full of praise. For once you can rightly
appreciate the positive effects of a rumor. CD20 will make you love music.
of musical reproduction, which is as faithful and transparent as possible. CD20 reaches that point
admirably and the thousands of owners of this model are only full of praise. For once you can rightly
appreciate the positive effects of a rumor. CD20 will make you love music.