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Denon, the developer of the world's first A/V components that combined the magic of 5.1 channel Dolby Digital (AC-3) with Lucasfilm's THX 5.1 technology, now elevates the performance standard with the new AVC-A1D A/V receiver. Packed with virtually every desirable feature for outstanding home theater and music surround sound enjoyment, the AVC-A1D is the only A/V component that provides optimized surround sound for both motion picture soundtracks as well as discrete multi-channel music surround. Powered by the newest high speed Analog Devices SHARC 32 DSP processors, the AVC-A1D includes Dolby Digital as well as DTS decoding, along with Lucasfilm THX 5.1 post-processing, entirely in the digital domain - world's first A/V receiver with this capability. The AVC-A1D is engineered for the future, with eight channel (7.1) inputs for future multi-channel formats, and eight channel (7.1) pre-amp outputs for a clear system upgrade path. Able to accommodate virtually any present or future video source, the AVC-A1D provides component video switching along with "S" and composite video switching, and nine digital inputs (including one for RF laser disc). Premium Burr-Brown 24 bit, 96 kHz DACs on all six channels with Denon's exclusive 24 bit Alpha processing for the main (left/right) channels provide superb low level resolution and detail. The power amplifier section is THX Ultra-certified, and provides 140 watts per channel into 8 ohms, with excellent low impedance drive capability. Technical Details Front End Inputs (analog) are provided for the following audio sources: AM/FM tuner (built-in); moving magnet phono; CD; MD/Tape 1; Tape 2 (with monitor) Inputs are provided for the following video sources: DVD; VDP (laser disc player); TV/DBS (TV input, or satellite tuner); V AUX (auxiliary video such as video game); VCR 1; VCR 2 All analog inputs are converted to digital via precision 20 bit oversampling A/D converters for delivery to the DSP section. An analog 2 channel bypass (direct mode) routes audio past the DSP section, providing straight-through signal purity. Record output function allows the user to select an audio source for direct delivery to the recording output jacks, while the user listens/watches another source. A separate Multi-zone output selector delivers a fixed level output to the multi-room output jacks (one stereo pair) for second zone music/soundtrack listening. Eight Channel External Inputs are provided for future 7.1 channel discrete surround formats. Newly proposed multi-channel music formats may have up to eight discrete channels - the AVC-A1D is prepared for the future of multi-channel music reproduction. Digital Inputs The AVC-A1D is provided with nine digital inputs. One input is dedicated to the laser disc RF function, which is used exclusively Dolby Digital-encoded laser discs, and is "polled" first when the VDP input is selected. The other eight digital inputs are all addressable - that is, they are not "locked" to any input, but can be assigned to the user's various sources according to the type of digital output jack found on each - this is done at the time of system setup. The AVC-A1D provides 3 addressable coaxial digital inputs, and 5 addressable optical digital inputs. For output to a digital recorder, 1 optical digital output is provided. The use of addressable digital inputs with both optical and coaxial types supported will allow virtually any combination of audio/video devices to be accommodated. Video Switching Composite and "S" video inputs are provided for: DVD; VDP; TV/DBS; V AUX; VCR 1; VCR 2 Composite and "S" video recording outputs are provided for: VCR 1 and VCR 2 A Record Output selector allows recording from one source to the VCR(s), while watching/listening to another source. In addition to composite and "S" video, the AVC-A1D also provides component video switching. In anticipation of forthcoming DTV (North American Digital Television) set-top decoder boxes, the AVC-A1D can accept a component video input (Y, R-Y, B-Y) signal from the TV/DBS input, and another from the DVD player. A separate dedicated component video output delivers the signals to the television monitor. For maximum video fidelity, the AVC-A1D features a wideband video section, with very low noise and extended frequency response. In order to preserve the video signal integrity, two types of monitor outputs are provided: Monitor 1 (composite and "S") features on-screen display; Monitor 2 (composite and "S") has no on-screen display. This lets the user set the system up initially using the easy Denon on-screen setup, and then, after the user becomes fully acclimated to the system configuration, the user can re-connect to the monitor outputs that have no OSD for the purest video pass-through quality. The component video output has no on screen display, for best video pass-through quality. With 27 MHz (-3 dB) bandwidth, the component video input signals are presented intact to the television monitor. Digital Signal Processing Section Denon A/V components have incorporated Denon's DDSC (Dynamic Discrete Surround Decoder) design concept for years. Essentially, DDSC features selected and dedicated processor(s) matched with selected premium ancillary devices, which in total work together to provide a superior surround sound processing function than the highly integrated (and lower cost) IC solutions used by competitors. The AVC-A1D's DDSC-D (Digital) all DSP decoder section is simply state-of-the-art. At the present time, no surround component from any company at any price offers this level of performance.
 At the core of the surround processor block are two of the brand new Analog Devices SHARC (Super Harvard Architecture Computer) 32 bit floating point DSP processor chips, performing in tandem. Each SHARC processor has a 50 MIPS (millions of instructions per second) computing speed, with an 80 MFLOPS (millions of floating point operations per second) sustained speed capability, with a peak throughput of 120 MFLOPS (each). One of the SHARC processors provides either the Dolby Digital or the DTS decoding (depending on the source), whilst the other processor provides THX 5.1 post-processing or other surround soundfield processing function. The Denon AVC-A1D is the world's first A/V component to incorporate dual SHARC technology, and the only product to use the fastest SHARC versions (single SHARC-equipped competitors use slower/lower capacity versions). To preserve the fidelity of the high bit data provided by the dual SHARC processor section, the AVC-A1D features full 24 bit 96 kHz DACs on all six audio channels. Unlike other processors which use cheaper integrated codecs, the Denon DDSC-D philosophy extends through the D/A section, featuring full 24 bit 96 kHz digital filters for each of the five main channels, followed by full 24 bit 96 kHz Burr-Brown premium PCM-1704 DACs for each of the five main channels. For the subwoofer/LFE output, the Burr-Brown 24 bit 96 kHz PCM-1716 filter/DAC combination is used. For the main (left and right) audio channels, the DDSC-D also incorporates Denon's proprietary AL24 (24 bit Alpha) processor. A dedicated DSP processor, the AL24 works with the digital filter to increase low level resolution and detail dramatically. The AL24 first appeared on Denon's DVD-5000 reference DVD player, and is incorporated here as well. After D/A conversion, analog signals are delivered to the volume control block and tone control block via audiophile-quality Analog Devices OP275 op amps, chosen for the wideband design and low distortion. The volume control has been substantially upgraded compared to earlier Denon models, both in specification as well as user convenience: Differential mode gain control, featuring dual gain circuits for each of the five main channels. This method eliminates any channel-to-channel tracking error, providing a remarkable .1 (1/10th) dB channel tracking accuracy over the entire volume control operating range. No analog (poten-tiometer-based) volume control can match this accuracy, which ensures correct soundfield precision at any volume level. Variable volume control ballistics, featuring a "smart" volume control algorithm. Via remote control, the volume is raised or lowered in gentle 1 dB steps. However, the master volume knob on the front panel has the ability to detect whether it is turned quickly or slowly and react accordingly. If the user slowly turns the volume knob up or down, the volume is adjusted in 1 dB increments accordingly. Give the knob a quick twist up or down, and the volume will raise and lower with greatly increased speed (much more like an analog volume control). Future Proof For a clear system upgrade path, the AVC-A1D features eight channel (7.1) pre-amp outputs, with all eight channels controlled by the master volume control. The AVC-A1D is prepared for the future of multi-channel music reproduction, regardless of format developments. Dual Mode Surround Speaker Operation Movies or Music? Until now, A/V enthusiasts were forced to choose which type of surround sound they prefer and configure their system accordingly:
The Denon AVC-A1D is the world's first A/V receiver to incorporate two sets of surround sound speaker terminals. Connect one pair of bipole or dipole surround speakers, placed high on the side walls near the prime listening position. Connect another pair of direct radiator speakers, perhaps choosing the same type as used for the front left/center/right, and place these at the rear corners of the room facing the prime listening position. The AVC-A1D features Denon's Personal Memory Plus feature, which remembers the various surround modes and settings for each main input. We recommend activating the dual surround mode speaker switching by using the THX function as the selector. During setup, configure as follows:
Then, it's as easy as touching the THX button -- choose Movie Surround with THX and the correct speakers are automatically engaged (even with separate level control memories). Choose Music Surround by disengaging the THX function, and the surround speakers automatically switch to the other pair (with a different memory level setting). The AVC-A1D provides the best possible movie and music surround performance, all at the touch of a button. Enhanced Bass Management One significant benefit of the THX Ultra-certification is the inclusion of superior bass management, which is responsible for ensuring that deep bass sounds do not arrive at the smaller center, front and surround speakers, at the same time ensuring that higher frequencies do not arrive at the subwoofer. The AVC-A1D feature's Lucasfilm's required 12 dB/24 dB Linkwitz-Riley crossover, with the crossover frequency at 80 Hz for optimum subwoofer-to-main speakers blend. During setup, the user can choose Large or Small according to the frequency characteristics of the system's speakers. A typical system would be configured as follows:
However, some users will have large full range left and right speakers, which may even include amplified woofer sections. In this case, if the user chooses Large for the main left and right speakers, the subwoofer will only reproduce bass that appears in the LFE ( .1 ) channel. Many movie soundtracks that are 5.1 encoded actually have little or no deep bass in the LFE channel, so after a period of inactivity, the subwoofer might go into sleep/standby mode, and then miss the first few seconds of any LFE content that may appear suddenly. The AVC-A1D allows the user to select Large for the main left and right speakers, and subwoofer on, and directs all low bass (within the main left and right and the LFE channels) to go to both the left and right speakers as well as the subwoofer. This can benefit users with large "tower"-type main L/R speakers with powered woofer sections, who also have a separate sub-woofer in their system. Power Supply/Power Amp Sections The AVC-A1D features a high current, high power, all discrete power amplifier block that features identical design and identical performance for all five channels. Featuring high current wideband discrete power transistors, each amplifier channel is rated at 140 watts into 8 ohms (RMS), and is torture tested during THX Ultra-certification with all five channels driving 3.2 ohms, putting out 1,250 watts of power! THX Ultra-certification requires stable operation at high volume levels into a wide variety of loudspeaker impedances. So, the AVC-A1D is provided with the strongest power supply incorporated in an A/V receiver. A massive 1200 VA toroidal power transformer is the heart of the power supply, with multiple stages and tight supply regulation for all stages. High current, low ESR power supply capacitors store the DC energy for delivery to the power amp block. The power amp block features side-mounted power transistors, with two separate heat sinks facing each other inward. For cooling, the AVC-A1D incorporates a smart "push-pull" dual fan system that is microprocessor controlled. This remarkable system is designed to keep the power transistors at correct temperature levels, as well as keeping fan noise from being intrusive during quiet passages. One fan is mounted at the front of the power block, drawing fresh air from a special venturi-vent mounted on the chassis bottom, centered just behind the front panel. The other fan is mounted at the rear of the power block, and exhausts via slots at the center of the rear panel. The system provides a four stage cooling action:
The system is thermally sensitive as well as output level sensitive. Should the fans be running at any time due to high power operation, and the soundtrack goes to a quiet passage, the fans are quickly cut back or shut off. This sophisticated system is designed to that the user should never be aware of the fan(s) operation, even if the AVC-A1D is mounted on an open rack within the listening area close to the prime listening position. Power, precision, fidelity, convenience, and full system upgrade capability are the hallmarks of the Denon AVC-A1D A/V Receiver. |
