DRAWMER DC2476 Digital Mastering Processor. REDUCED to $ 2,995.

Manufacturer's Description: The Drawmer DC2476 is an extremely sophisticated, all-digital stereo mastering processor designed for use in demanding recording and broadcast applications. Both analogue (balanced XLR) and digital (AES/EBU and S/PDIF) I/O are provided as standard. The audio converters are 24-bit and the digital output can be either 16, 18, 20 or 24-bit at sample rates of up to 96kHz. Noise shaped dithering is included and Word Clock input and output is available. Main Features 24 bit A/D - D/A conversion 32, 44.1, 48, 88.2 or 96kHz In/Out sample rate Multi band 'Bootstrap' compression Gain Normalisation for maximum loudness Multi band expansion and limiting Five band digital EQ with ?18dB range Dynamic EQ with full band compressor Multi-band tube modelling for musical tone shaping De-essing Word Clock In/Out, Midi In, Out and Thru Three band stereo width control Expert factory patches and user memory Autofade PCMCIA slot for parameter transfer to other Drawmer DC2476 units AES/EBU, SPDIF digital input / output connectors Balanced XLR analogue input / output connectors Why 96kHz? Digital processing has until now been confined to 48kHz sampling frequency. In order to achieve the required bandwidth for professional audio, a very severe low pass filter at 23kHz is required to separate analogue signal frequencies from the clock frequency otherwise unpleasant aliasing will occur. This requires the use of a FIR digital filter which is part of the A/D and D/A converters. Unfortunately these filters cause what is known as ?time smear?, where short transients are smeared over a longer time period giving loss of HF detail. At 96kHz sample frequency, the low pass filter is less severe and at twice the frequency, so time smear is considerably reduced. A second important consideration is the increased audio bandwidth up to 40kHz. This allows harmonics which extend above human hearing to be generated and preserved. These harmonics, although not audible themselves, make a contribution to the sound quality. Finally, the user interface has been designed to make the Drawmer DC2476 as simple to operate as possible. In fact, once you?ve got used to using the cursor buttons, the Adjust knob and the Adjust knob push switch to move around the various screens and their parameters, operation is almost entirely intuitive. Custom graphics are used wherever possible to monitor the processor function and its adjustments while front panel LED bargraph meters constantly monitor the input and output signal levels, limiter activity, plus the amount of gain reduction being applied in each of the three frequency bands. Effects: The signal chain comprises six blocks in addition to the Input and Output sections. The Dynamic EQ and Equaliser blocks are of necessity full-band (they affect the entire signal), while the Expander, Compressor, Limiter and Tube Drive sections that follow are all three-band. Multi-Band Processing: The main purpose of the split band section is to allow the three different parts of the audio spectrum to be treated independently so as to minimise side effects, but each of the dynamic processes may be adjusted differently in each of the three bands if required. This opens up many creative possibilities for introducing level dependent spectral changes. The user may adjust the two crossover points that define the three frequency bands into which the signal is split prior to processing. The crossover frequencies may be accessed from the second page of any of the split-band effects blocks. Gain Management System: Since both the Dynamic EQ, Compressor and Parametric Equalisers are capable of increasing overall gain, the GAIN MANAGEMENT treats them as a single set of functions, since gain applied in the dynamic EQ or Compressor can be reduced again in the main EQ. Once both EQ?s have been adjusted for best results, use Gain Trim on either DQ or EQ pages to reduce gain to keep Gain Reduction to a minimum. Input Page The input page shows the signals as a graphic display of the signal level passing to the effects functions. A dotted line at the top of each display shows the maximum signal level (0dBfs). Use the control knob to adjust input levels. Push the knob to select Left/Right/Both, then turn to adjust. The internal gain management will reduce gain if signal peaks are too high and would otherwise cause distortion. This is shown on the input screen GR meter. Adjust gain so that the GR meter shows minimum activity, responding only to the signal highest peaks. top of page Dynamic EQ/Full Band Bootstrap Compressor A high performance floating threshold dynamic equaliser consists of a single band parametric EQ with up to 12dB Boost or Cut, under dynamic control. Frequency is adjustable from 64Hz to 8kHz in semitone increments with bandwidths from 0.25 to 3 octave. This is shown graphically on the LCD screen as a familiar EQ curve. Dynamic gain is variable from -12dB to +12dB. Positive values produce enhancement of the selected frequency band, whilst negative values produce a reduction. Negative values may be used for frequency-selective de-essing or de-popping while positive values ?expand? the selected frequency range, making it more prominent. Because the process is dynamic, low level signals will not be treated, and when enhancing low frequencies to add punch to a mix, this can help avoid muddying the mid range while keeping the bass sound tighter than trying to do the same thing with conventional EQ. Selecting ?Filter? puts the DC2476 into filter listen mode so that filter characteristics may easily be evaluated. Pushing the knob when adjusting Frequency or Bandwidth selects output as Normal or Filter. Selecting Filter enables the filtered signal to be monitored without processing. This helps in locating the exact frequency to be processed by the Dynamic EQ and is of particular value when using negative DGAIN values. Normal is auto selected when other parameters are selected or when leaving the Dynamic EQ block. Though the DC2476 includes a three-band compressor, it can sometimes be useful to apply a degree of compression prior to equalisation. For this reason, the DQ section also includes a full-band compressor. Like the later three-band compressor, this has a bootstrap characteristic where the level of low level signals is increased rather than high level signals being decreased. The position of the dotted line across the display window shows by how much low level signals have been increased. The compressor section has three controls. COMP adjusts the amount of compression and has a range from ~24dB to +24dB. Positive values compress the full band signal whilst negative values are used to de-compress or expand material which is already over compressed. Attack and Release controls are semi-automatic, programme adaptive, providing a wide range of user control and at the same time taking account of the dynamics of the signal. The dotted line across the graphic display indicates the amount of compression (i.e. the amount of gain applied at low levels). A GR bar display to the right of the screen and connected to the dotted line indicates gain reduction. This shows the gain being reduced back to 0dB in response to high level signals. Conversely, when COMP is set to a negative value, the dotted line shows the attenuation applied to low level signals, with the bar meter showing rises in gain towards 0dB as the signal increases in level. Positive Dynamic EQ (DGAIN) and Compressor (COMP) settings can produce signals which could cause overload. The Gain Management will reduce the signal level when this occurs. This is shown on the on screen GR meter and is also affected by any boost applied by the EQ section. top of page 5 Band Equaliser The equaliser section consists of an analogue modelled 5 band parametric equaliser with a wide range of frequency and bandwidth. Up to 18dB Boost or Cut is available on each band. Bass and Treble bands have selectable Shelf or Bell (Peaking) filter shapes whereas the 3 mid bands are bell only. All bell filters have a frequency range from 32Hz to 22kHz in 1 semitone steps. Bandwidth range is from 0.08 octave (1 semitone) to 5 Octaves. The graphical display shows a plot of the selected frequency curve. When each band is selected, a small vertical bar appears across the 0dB line on the graph. This indicates the centre frequency of the selected band, which is useful in locating the position of each band, either before Cut or Boost is applied, or when a complex EQ curve is in use. top of page Multi-Band Expander/Gate Expanders are generally used to remove unwanted noise during what should be passages of silence, but are also a means of ?undoing? gain at very low levels due to compression, where the noise floor is pulled up to an unacceptably high level. Threshold, Ratio, Attack, Release and Range adjustments allow a wide range of control, with Program Adaptive techniques used to make real time adjustments depending on the nature of the signal. The incoming signal levels of each band are displayed in the Threshold box, rising from -96dB towards 0dB. Rotating the knob clockwise takes the wider threshold bars down towards the signal. As the signal approaches threshold, the gate begins to open at the Attack rate until, as the two bars touch, the gate will fully open. This gives a clear indication at all times of where the signal is in relation to the threshold. As the signal level drops below the threshold bar, the expander begins to reduce gain by an amount dependent on the Ratio setting and at the Release rate. The onset of expansion causes the appropriate expander LED under the main output VU meters to illuminate. The Range control is used to limit the maximum amount of expansion, regardless of Ratio settings. This can be used to prevent excessive expander activity and improve transparency. top of page Multi-Band Bootstrap Compressor Conventional compressors reduce the level of audio peaks, which means make-up gain has to be applied to restore the same peak level. The Drawmer DC2476 works the other way around by instead increasing the level of quieter signals and leaving the peak levels at their original values. This makes setting up far more intuitive when adjusting the individual bands of a multi-band compressor and also avoids the necessity to juggle the make-up gain control settings. The purpose of the Bootstrap Compressor is to pull signals up towards digital full scale. This combined with Program Adaptive algorithms provides punch, enhances spectral detail and delivers well controlled power. Threshold, Ratio, Attack, Release and Gain adjustments are available. Simply increase Threshold and Ratio. top of page Multi-Band Limiter/Stereo Width The three-band limiter is designed to allow peaks signal levels to be controlled without introducing audible side effects unless the amount of limiting is considerable. This may be used to maximize the subjective level of recordings being mastered without affecting the overall sound or peak level, but it is also possible to adjust the release time of individual bands to provide the most transparent results. The limiting threshold is preset to digital full scale so that limiting only occurs when the signal level is such that it would otherwise have clipped. Spectral changes can be made by balancing the level of the three frequency bands in the Output section, and as this is still under the control of the automatic gain management system, it isn?t possible to clip the output signal. Separate stereo width controls are also provided for the three frequency bands, enabling the width to either be narrowed to mono or to be widened further than the original. One major benefit of having independent width control for each of the bands is to allow the high frequencies to be spread across a wider soundstage without affecting the low frequency end. Excessive low frequency widening may lead to phase problems, and in those instances where a vinyl record is the end result, it may be beneficial to narrow the stereo image of the bottom band, or even reduce it entirely to mono. This can reduce cutting problems due to low frequency phase differences. top of page Multi-Band Tube Modelling The tube emulation in the DC2476 is based around an algorithm that mimics the transfer characteristics of a typical triode tube. This introduces both level dependent harmonic distortion and compression, making it possible to recreate the tonal warmth associated with vintage tube equipment. However, because the Tube Saturation section is spread over three frequency bands, the enhancement effects of the tube emulation are confined to their own parts of the frequency spectrum. The outcome is that the signal remains smooth and musical, even when relatively high amounts of processing are being applied. Furthermore, because the drive is independently adjustable in all three bands, it?s possible to use this stage of the DC2476 to achieve sophisticated spectral reshaping. For example, increasing the tube drive in the high band creates an effect not unlike a harmonic enhancer, whereas adding more low band drive adds bass energy and warmth. Control is extremely simple as the only adjustable parameters are the drive settings of the three bands. top of page Output Page The Output section provides three level trims for the three frequency bands prior to summing. Once the signal has been summed it passes through an auto stereo fader. The Fade out time may be adjusted from 1 second to 1 minute and a "fade out" or "fade in" may be initiated by pressing the Adjust knob switch. Pressing a second time reverses the direction of the fade. The Fade Up time is always fast and can not be adjusted. When the Output page is left a Fade Up will occur. As a Fade starts, the FADE LED is illuminated. The second page of the Output section allows the user to choose from three different fade curve shapes. Specs: ANALOGUE INPUT Connectors: XLR Balanced (Pin 2 Hot) Impedance: 10 KOhms Max. Input Level: +21 dBu Input CMR: Better than -50dB A to D Conversion: 24 Bit Dynamic Range: A/D -112dB Unweighted at 48KHz Crosstalk: -80dB @ 10Hz to 20kHz ANALOGUE OUTPUT Connectors: XLR Balanced (Pin 2 Hot) Impedance: 50 Ohms Max. Output Level: +21 dBu Output Balance: -35dB@1KHz D to A Conversion: 24 Bit Dynamic Range: -108dB Unweighted THD: >0.008%@1KHz, +10dBu Frequency Response @ -1dB 96kHz 7Hz - 44kHz 88kHz 7Hz - 41kHz 48kHz 7Hz - 22kHz 44.1kHz 7Hz - 20kHz 32kHz 7Hz - 15kHz Crosstalk: -80dB @ 10Hz to 20kHz DIGITAL INPUTS AND OUTPUTS AES/EBU In/Out: XLR S/PDIF In/Out: Coaxial, RCA Type Sample Rates: 32,44.1,48,88.2 and 96KHz INTERNAL BATTERY Type: Varta Mempac Ni-MH Rating: 3.6V 150mAh PC-CARD INTERFACE Connector: Type 1 PCMCIA SRAM card Standards: PC-Card 2.0, Jeida 4.0 standard Card Format: upto 256Kb CONTROL INTERFACE MIDI: In/Out/Thru: 5 Pin DIN GENERAL Power Requirements: 30VA Fuse Rating: T500mA for All voltages. CONFORMING TO BS EN 60127-2:1991 SHEET III Fuse Type: 20mm x 5mm Class 3 Slow Blow 250Volt working Case Size (mm): 482(w) x 44(h) x 250(d) Weight (incl packaging): 5KG Dimensions: 482 * 44 * 250 mm Shipping Weight: 5 Kg