Accuphase DC 330 Brochure
This is the 6 pages manual for Accuphase DC 330 Brochure.
Read or download the pdf for free. If you want to contribute, please upload pdfs to audioservicemanuals.wetransfer.com.
Extracted text from Accuphase DC 330 Brochure (Ocr-read)
Page 1
Leaving the analog/digital division far behind – this digital preamplifier features ultra high-speed DSP and complete readiness for the new generation of super high quality audio sources. The newly developed MDS (Multiple Delta Sigma) converter with 24-bit ultra high precision resolution results in dramatically enhanced performance. Witness a new dimension of audio perfection. The DC-330 builds on the foundation of the DC-300, with some significant advantages over its predecessor. Ease of use has been fur ther enhanced, and latest digital technology and redesigned circuitry assure total compatibility with the emerging new generation of top-quality audio sources such as SACD and DVD-Audio. The digital volume and tone controls function with previously unattainable precision, yet their smooth operation feel is on a par with the best of analog equipment. Internally, the DC-330 features ultra high-speed digital processing performed by a latest-generation DSP device. D/A conversion is handled by an innovative MDS (Multiple Delta Sigma) converter which boasts superior accuracy. This makes the DC-330 capable of bringing out the full potential of a new breed of audio sources that is just emerging, such as the Super Audio CD (SACD) and DVD-Audio. During the development of this amplifier, countless listening sessions were held to arrive at the detailed, rich sound that is a hallmark of every Accuphase product. In a preamplifier, the part that has a decisive influence on the sonic end result is the section where adjustments such as volume, tone, and loudness compensation are carried out. In the digital DC-330, this task is handled by an extremely fast DSP that assures a drastic leap in performance, achieving outstanding signal-to-noise ratio, amazing channel separation, and totally negligible distortion. The overall result is utterly natural and realistic sound with full control over every vital aspect. To provide complete flexibility with a view to future expansion, all inputs and recordingoutputs of the DC-330 are implemented as option boards. The option board slots suppor t the ADB2 (Accuphase Digital Bus 2) interface which accommodates also formats such as SACD and DVD-Audio. The DC-330 comes with a line input board for analog signals and a digital input/output board installed as standard equipment. As a perfect blend of analog operation feeling and sophisticated digital technology, the DC-330 transcends the mechanistic division of analog or digital, fusing them both into a higher dimension that is devoted solely to the enjoyment of music. Fully digital preamplifier with ultra high-speed DSP and support for high sampling rates: 2.8224 MHz/1-bit and 192 kHz/24-bit. Figure 1 shows the block diagram of the DC-330. Digital sources are connected via coaxial or optical inputs located on option boards. All option board slots of the unit are ready to handle the bit stream output of a SACD player which uses 2.8224 MHz/1-bit, as well as the 192 kHz/ 24-bit signal used for DVD-Audio. Other high-quality formats that may emerge will also pose no problem to the DC-330. After the input, an ultra jitter-free PLL circuit extracts a high-precision reference signal totally free from the adverseeffects of pulse transmission distortion and jitter. After conversion into the internal format of the DC-330, a DSP (Digital Signal Processor) operating at extremely high speed performs some of the major tasks that are handled by a preamplifier, such as tone control, loudness compensation, as well as mono and phase switching. All of these adjustments are accomplished entirely in the digital domain. An ultra high-speed isolated digital coupler ensures effective electrical separation between the digital section encompassing the DSP and the D/A converter and subsequent analog segments of the amplifier. After digital volume, balance, and attenuation processing, the signal reaches the newly developed MDS type D/A converter which produces an analog signal of utmost precision. A 3-pole linear phase low-pass filter then removes any remnants of the digital process, before sending the signal to the balanced and unbalanced outputs. Innovative MDS (Multiple Delta Sigma) converter reduces distortion to theoretical limits and assures outstanding S/N ratio The D/A converter which has considerable bearing on the sonic end result is a newly developed type that provides excellent performance in all aspects. The MDS (Multiple Delta Sigma) principle employs several delta sigma type converters in a parallel configuration which results in a drastic precision enhancement. The delta sigma principle combines oversampling with noise-shaping (a kind of digital feedback) which projects the amplitude information of the digital signal onto a time axis for precise conversion. Figure 2 shows several delta sigma converters which are fed with the same signal and whose outputs are combined to arrive at the overall waveform. In the DC-330, six delta sigma converters are operated in parallel, which results in a perfor- mance improvement by a factor of 2.45 (=Ö6). An impor tant characteristic of the MDS principle is that the performance benefits are achieved regardless of signal Fig. 1 DC-330 block diagram Ultra high-speed DSP Unbalanced Outputs Left Analog Outputs 1 2 Balanced Outputs 3-Pole Linear Phase Low PassFilter Balanced Buffer1 2 Option Slot 8 Analog Input AI2-U1 Option Slot 7 Digital Input/Output DIO-OC1 Option Slot 6 Option Slot 1 Coax RX Opto RX 24-bit A/D Converter Opto RX Opto RXCoax CoaxMaster Clock DAI Decoder DAI Encoder Ultra Jitter-Free PLL Tone MonoComp Phase Volume Balance Attenuator Digital Isolator MDS 24-bit D/A Conver ter ×6 Opto RX Coax RX External DSP Option ( DIO-OC1) Volume Control Outputs Option ( DIO-OC1) VolumeVolume Information Digital Filter Volume Balance Attenuator MDS 24-bit D/A Conver ter ×6 Left Right Digital Isolator Unbalanced Outputs Right Analog Outputs 1 2 Balanced Outputs 3-Pole Linear Phase Low PassFilter Balanced Buffer1 2 DSP Digital Filter DS DS
Page 2
frequency and signal level. Therefore noise at very low signal levels that was difficult to contain with conventional delta sigma converters now could be drastically reduced. The audible result is music reproduction emerging from utter silence with an impressive sense of clarity and nuance. Volume control with smooth analog feel A massive knob on a precision-machined shaft rotates a disc with star-shaped slits which Fig. 2 MDS type D/A converter principle generate a series of pulses in a phase detector. These pulses are utilized by a microprocessor to govern the volume control function. For the user, the volume control of the DC-330 operates with a silky smooth and natural feel that perfectly matches the audible change in volume. The current volume setting is indicated by the numeric display and also by an array of LEDs on the circumference of the control. This lets you check the setting at a glance. Linear phase analog filters provide superior characteristics The analog filter, which serves to remove aliasing noise in the extreme upper frequency range, is a 3-pole linear phase type filter with outstanding phase characteristics. The cutoff frequency is optimized to minimize phase shift within the passband. Strict selection of all filter components assures sonic purity and total musical accuracy. D/A converter with printed circuit boards made from Teflon (glass fluorocarbon resin) with low dielectric constant and low loss The D/A converter boards use a substrate of nThis photograph shows the DC-330 with separately available option boards installed and with the shielding cover removed. nPCB assembly with analog output connectors (balanced and unbalanced, 2 each) and MDS D/A converter (2 boards for left and right) using Teflon* (glass fluorocarbon resin) substrate with low dielectric constant and low loss. nSupplied remote commander RC-24 Allows input selection and adjustment of volume, tone control on/off, loudness com- pensator on/off, attenuator on/off, and other functions. glass fluorocarbon resin which has a stable, low dielectric constant as well as superior heat resistance and high-frequency characteristics. Using this material for the audio circuitry assures signal transmission with utmost purity, resulting in a clear improvement in perceived signal- to-noise ratio. In the DC-330, gold-plated copper DAC #1 #2 S 1 e1 S2 e2 Sn-1 en-1 S0 e0 Sn en #1 # n MDS output Digital inputSignal Conversion error