DENON DCD-1650/DCD-1650G

Commentary

A CD player with a Lambda S. L. C4D/A converter.

The D/A converter is equipped with a 4D/A converter of Lambda S. L. C.
Lambda is an abbreviation of LAMBDA (Ladder-from Multiple Bias D/A). It uses a newly developed LSI to divide digital data into two systems, each of which is shifted by applying a digital bias in the + and - directions near the 0 cross point to eliminate the 0 cross distortion in principle.
In this method, when the digital data is smaller than the shift amount, there is no value crossing the original 0 cross point, so there is no 0 cross distortion. Furthermore, by adding the two data after D/A conversion, the DC component is removed and the two data are combined. Thus, an analog output with no 0 cross distortion can be obtained. These two data have no MSB inversion and no 0 cross distortion in the combined waveform. Moreover, even if there is an error in any bit, the distortion is reduced to 1/2 by averaging the two signals.
In addition, if the digital data is at a level larger than the shift amount, it will cross the original 0 cross point, which may cause distortion. However, this distortion is also removed by the MSB correction of the S. L. C (Super Linear Converter). In addition, when there is no shift operation or only a few times in a single song at the peak level (approximately 99.6% or more of the maximum level), the lambda function stops shifting operations and uses the converter's dynamic range to ensure a wide dynamic range.
The DCD 1650 uses a differential amplifier configuration to improve the S/N ratio and distortion factor as well as to enhance the ability to reproduce small signals. Moreover, the output of one side of the lambda processor is delayed by a half period of 8 fs and combined at the output stage of the D/A converter to achieve the same operation as 16 fs. This allows unwanted noise to be shifted to the higher frequency range, and combined with the use of a GIC analog filter to improve the phase characteristics.

The digital filter is equipped with an 8 x oversampling digital filter. By raising the sampling frequency by 8 x, the high-frequency noise of 24.1 kHz or higher included in the output of the converter is shifted to the higher range, making it easier to remove with the analog filter.

The analog circuits after the D/A converter are designed to be independent on the left and right sides. Moreover, the analog circuits are completely independent on the L/R according to the signal flow, thereby eliminating interference between channels.

The power supply section uses a large power transformer and a large-capacity smoothing capacitor.

Aluminum extruded material is used for the top cover.

Power cord with polarity display is used.

Equipped with Denon's own digital pitch commander, the playback pitch of CDs can be changed up to ± 12.0%.
This feature allows the digital PLL to adjust the pitch of the CD playback in 0.1% increments.

It is equipped with peak search which can find the maximum recording level of the disk with one touch operation.

Equipped with a time specifying type time edit function and a 2-segment type auto edit function.

It is equipped with a fader function that allows you to fade in / out at your favorite place or fade out at a specified time during performance.

It is equipped with up to 20 program plays.

Display brightness can be changed to 4 levels.

It is equipped with a remote control electric volume that can be used as headphones.

There are 2 kinds of variations, black type DCD 1650 and gold type DCD 1650 g.

Wireless remote control is included.

Model Rating

Type	CD Player
D/A conversion part system	Real 20-bit Lambda Super Linear Converter (4D/A converter type)
Filter	20-bit 8 x oversampling digital filter GIC third order analog filter
Frequency characteristic	2 Hz to 20 kHz
Signal-to-noise ratio	115dB
Dynamic range	100dB
Total harmonic distortion factor	0.0018%
Channel separation	110dB
Interchannel phase difference	3 degrees or less
Output voltage	Fixed : 2V/10k Ω load Variable : 2V/10k Ω at load
Headphone jack	Maximum output 10mW/32 Ω load, Line variable output combined with volume
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	19W
External dimensions	Width 470x Height 122x Depth 360 mm
Weight	11.3kg
Attachment	Wireless Remote Control RC-232