Denon AVR-5600 AV-receiver
Denon's AVR-5600 comes as close to fulfilling my A/V receiver wish list as anything I've seen. First of all, it's a powerful beast, rated at 140 watts per channel into 8 ohms with all five of its channels driven. As with most A/V receivers, the five-channel rating is specified at 1 kHz (with 0.7% distortion), but the stereo rating (also 140 watts but from 20 Hz to 20 kHz with 0.05% THD) hints that real-world performance is likely to be better than claimed. Second, the AVR-5600 is equipped with a Dolby Digital Surround (AC-3) decoder and is Home THX-certified in both Dolby Pro Logic and Dolby Digital Surround, i.e., for both matrixed and discrete surround soundtracks. Its Dolby Digital section can accept an RF-modulated AC-3 signal from today's laserdisc players without an external box, as well as direct AC-3 bitstreams from DVD players (and, in a year or two, HDTV receivers). What's more, the AVR-5600 can accept the Dolby Digital bitstream from any of its four digital inputs.
In a novel twist that provides the AVR-5600 with unusual versatility, the receiver's setup menus enable you to allocate any digital input to any of seven program sources. However, only one digital input, "Optical-3," is accompanied by an output (also optical) to feed a digital recorder. Three sources ("Phono," "Tape-2," and the built-in tuner) cannot be assigned to digital inputs. When you select a source, the AVR-5600 uses the digital input, if one has been allocated; otherwise, it uses the analog input whose name corresponds to the source. For digital inputs, the Denon analyzes the input bitstream to determine whether it's standard PCM or needs to be fed through the AC-3 decoder. Thus, the AVR-5600 handles all current (or soon-to-exist) audio program sources-stereo or matrixed analog, stereo or matrixed digital, and discrete 5.1-channel digital (including RF-conveyed AC-3 from laserdiscs). Like most A/V receivers these days, this one can display menus, settings, and even a speaker-setup diagram on your TV screen.
The AVR-5600 has provisions for five audio/video and five audio-only sources (counting its tuner), including two VCRs and two audio recorders. The tuner features 40 presets in five banks of eight and automatic memorization of local stations (with manual override). It also incorporates the Radio Data System (RDS), which Denon has persistently championed for car and home FM. As more and more FM stations start broadcasting with RDS, this will enable you to search among the RDS stations in your area to find a particular type of program, get traffic reports, display transmitted text (such as song and album titles), and receive emergency alerts.
The AVR-5600 has recording outputs to complement its audio tape and VCR inputs and, of course, an output for your TV monitor. Denon also provides stereo connections for an audio system and an additional TV in a second room. All connections are on the back, and all video signals (except that for the second TV) are carried in S-video and composite-video forms. All audio and composite-video RCA jacks are gold-plated, as is the front-panel headphone jack. There are preamp outputs for each of the five main channels and for a powered subwoofer but no input connections for the internal power amps. Since the AVR-5600's five power amps are identical, the omission is justified; there's little purpose in swapping identical power amps.
The amplifier outputs are multiway binding posts that accept single or double banana plugs. Parallel-connected pairs of posts are provided for the three front speakers, to facilitate bi-wiring. Three switched convenience outlets, with a total power rating of 120 watts, are provided. The FM antenna connects to a 75-ohm F connector; the AM loop connects to a pair of wire clamps. A grounding terminal is near the phono input, for easy connection to a tone-arm or a turntable frame.
The AVR-5600 may not win any beauty contests, but its front panel is inoffensive and, when the hinged door at the bottom is closed, rather simple. The "Power" button is on the left, "Master Volume" is on the right, and below the display are 11 small selectors: "AC-3 RF," "Phono," "CD," "Tuner," "VDP/DVD," "TV/DBS," "VCR-1," "VCR-2," "V.AUX," "DAT/Tape-1," and "Tape-2/Monitor" (with a nearby LED to indicate when that monitor is in use). I prefer individual program selectors like these to cyclic selectors, because they're faster and easier to use and eliminate an on-screen menu. (I also approve of Denon's use of relays rather than solid-state switches to route signals, because relays are less likely to inject noise and distortion.) Behind the hinged door are 16 buttons that control surround modes, input adjustments, tuner presets, and recording/multiroom program selection. These are flanked by a "Phones" jack on the left and "Bass" and "Treble" knobs on the right.
Except for manipulating the tone controls, you can select anything from the remote that you can from the front panel, albeit sometimes in a different fashion. For example, selecting sound modes via the remote involves cycling through the modes, whereas the panel offers direct access to most of them.
These sound modes are "Direct" (which bypasses the tone controls when you're listening in stereo), "Stereo" (which activates the bass and treble controls), and six surround options. The surround modes are "Dolby Surround" (which automatically chooses Dolby Digital over Pro Logic if the receiver is fed an AC-3 program), "Home THX Cinema" (which adds Home THX enhancement to whatever Dolby Surround mode is used), "Mono," "Wide Screen" (DSP-enhanced Dolby Surround), "5CH Stereo" (which redistributes a stereo source among all speakers), and "DSP Simulation." The last chooses, in cyclic fashion, among five simulated surround modes ("Super Stadium," "Rock Arena," "Jazz Club," "Classic Concert," and "Matrix"). Both "Home THX Cinema" enhancement and the various simulation modes are implemented in a Motorola 56004 DSP chip.
Three buttons behind the hinged panel control the audio input settings for each source and, once adjusted, remain associated with that source unless you reset it. The first two raise or lower input level, and the third toggles "Analog/Digital" input connections. (In retrospect, it strikes me that this third switch probably lets you use four more program sources than appear on the front panel: Just connect whatever sources you wish to the analog inputs that correspond to the four source positions you allocated digital inputs to, and then use the toggle to select either input set.)
Next come three tuning buttons ("Shift," "Down," and "Up"). With the last two buttons on the bottom row, you set the program source to be fed to a second room and to the recording outputs. The "REC/Multi Source" button cycles through the 10 possible sources or, in its 11th position ("Source"), uses whatever source is set by the main program selector. The other button, "REC/Multi Mode," assigns the selected source to the recording outputs or to the multiroom jacks.
The AVR-5600's display is in three sections. On the right is a two-digit master volume LED that's always active. On the left are 10 small LEDs. Six of them indicate the presence of a Dolby Digital AC-3 signal and how many channels it contains. (AC-3 is just a compression system and can be used to carry stereo or mono audio as well as 5.1 -channel surround.) The other LEDs indicate when a digital (rather than analog) input is in use, when Dolby Surround decoding is on, whether there are signals in the low-frequency effects (LFE) channel, and when circuits (presumably the inputs) overload. Unfortunately, the LEDs' labels are essentially unreadable, which makes the array virtually useless except as decoration. The display's center section is a fluorescent panel whose brightness can be set to three different levels or turned off by the remote's "Dimmer" button. If you turn the display off, it comes back to life briefly when you change the program source or other settings.
The remote can control three audio and three audio/video sources. It's a universal remote, preprogrammed with the control codes of equipment from several major companies and capable of learning the codes of other makers' equipment. The remote has 59 buttons and two switches. The buttons don't illuminate, but they are color-coded, clustered in groups, and shaped differently to give a tactile indication of use. Twenty-one "infrequently used" buttons are covered by a hinged panel, which keeps them out of the way. Strangely, the major tuner controls ("Tuning" up/down, "Band," "Mode," "Memory," "RDS," and the buttons that activate RDS program search and text display) are among those that are hidden.
The setup buttons are also behind the remote's hinged panel. "Enter" brings up the main onscreen menu ("Surround Parameters," "System Setup," and "Menu Off"). The on-screen display indicates the active selection by a pointing finger, with upward- and downward-pointing arrows marking the selections above and below. The indicator is moved by up/down "Cursor" buttons; "Enter" activates your selection.
The main menu's "Surround Parameters" option is used for toggling the Denon receiver's "Cinema EQ" circuit on and off and for adjusting "Room Size" and "Effect" levels when you are using DSP-based enhancement.
The "System Setup Menu" offers eight submenus. These are used for matching the AVR-5600's individual-channel frequency responses, delays, and levels to your speaker setup; controlling a peak limiter for the subwoofer; allocating the digital inputs; toggling the AC-3 decoder's dialog normalization on and off; setting tuner presets automatically; and controlling the on-screen display. Several of the submenus are self-explanatory, but four of them deserve a bit of explanation.
In the "Speaker Configuration" submenu, you inform the AVR-5600 whether you have center or surround speakers and whether each speaker, except a subwoofer, is small or large. (More and more microprocessor-controlled surround decoders use this setup method, which is clearer and more to the point than choosing "Center, Wide" for a large center speaker and "Center, Normal" for a small one.) If you indicate you have small main speakers, you're offered a choice of only "Small" or "None" for the center and surrounds, and the AVR-5600 redirects bass energy accordingly.
To set "Delay Time," you enter the distances between the listening position and each speaker, in feet or meters, rather than having to calculate and enter delay times per se. The left and right front speakers are assumed to be equidistant from the viewing position, so one entry serves both.
For "Channel Level" adjustments, you can press buttons to move test tones from speaker to speaker or have these tones cycle around the array automatically. Once you've activated "Test Tone Start," an array of speaker icons and five channel-level adjustment bars appear on-screen to guide you through the procedure.
The "Subwoofer Peak Limit LEV." submenu enables you to activate or deactivate a peak limiter on the subwoofer channel. It also helps you determine what peak limiter level will give you maximum bass from your sub without excessive distortion.
Use and Listening Tests
So what's going on? I've not seen a really bad DAC in a CD player in some time, and I had assumed I could count on basically decent DACs in processors and A/V receivers. I have felt that my time would be better spent exploring output power, high-level distortion, surround sound characteristics, and the like. But it takes six DACs to implement Dolby Digital, and I guess that's put pressure on the manufacturers to cut corners. Denon is not the only one to have done so, but I'm still surprised to find it here, especially since the company claims to use 18-bit DACs in the AVR-5600.
Could the right-channel DAC be a fluke of my particular sample? Perhaps, but the left-channel converter, while decent, isn't outstanding either. There are four more DACs in this receiver; unfortunately, they're not easily accessible for measurement. I have to assume that what I can measure is representative of what exists.
Could I hear the problems I measured? Can't say I did on Dolby Pro Logic or Dolby Digital movie soundtracks, but I could hear something amiss on well-recorded stereo. I preferred the sound of the DAC in my Sony CDP-XA7ES player to the sound of the DAC in the Denon. Okay, so the Sony's converter is extraordinary, and the player alone costs a bit more than the AVR-5600. But I also preferred the MASH converter in my old Sansui CD-X711 to the Denon's DAC.
Movies fared much better than CDs; maybe I become less critical with so much going on. Yet I didn't feel that the AVR-5600 provided quite the same bass impact as my reference audio system when I listened through the same speakers and subwoofer. I can't make quick and direct A/B comparisons in my home theater (nor can one match levels quite so precisely when using digitally adjusted attenuators), so I'm less sure of my conclusions-but that's how I felt.
As I said at the beginning of this review, the Denon AVR-5600 fulfills my wish list of features better than other receivers I've seen. A more robust and generally capable A/V receiver would be hard to come by. It could use a better manual (Denon tells me one's in the works), and it could also use a few modifications to improve the converters and remove a few operational oddities (limited bass response in some channels under some conditions, swaybacked response, etc). Some of these may require only software modifications (so much is done in software these days!); others may require component changes. I hope Denon will make them, because the AVR-5600, which is already a very good receiver, has the potential to be a really great one.