Home Theater FAQ		return to faq index

Always choose Small for center channel (we know of no dedicated center channel speakers that are flat to 20 Hz). Choosing Large setting for the center channel will always result in reduced bass, as well as substantially degraded dialog quality.

Always choose Small for the surround channels as well. The bass management within the surround decoder will then route any deep bass information present to the subwoofer.

If your system has no subwoofer, then choose Large for the left and right speakers, keeping the center and surrounds set to Small. Any deep bass present in any channel of the program material will be routed to the left and right speakers - this would include any deep bass sounds encoded in the ".1" or LFE (Low Frequency Effects) channel.

Some have advocated a dedicated subwoofer for the LFE channel, while using very large and bass-capable main left and right speakers (set to Large). This arrangement is usually less satisfactory, as most soundtracks actually contain little or no information in the LFE channel. Often, after a prolonged period of no LFE activity, the subwoofer goes into "standby" mode, and when a burst of LFE deep bass comes along, the subwoofer has to "wake up", causing some of the material simply not to be reproduced.

We recommend that the subwoofer be used for deep bass reproduction of all bass within the soundtrack, not just for whatever might be in the LFE channel (assuming there is any information in the LFE channel for a particular program). Choose subwoofer Yes and Main/Center/Surround to Small for the best overall results.

The first DDSC circuits were designed to accurately decode analog-based Dolby Pro Logic sources. DDSC-Digital is an all-digital system that handles Pro Logic decoding entirely in the digital domain as well as the latest Dolby Digital sources.

DDSC-Digital circuits feature separate analog-to-digital converters, surround processing and signal enhancement microprocessors (using Zoran and Motorola DSP ICs), and final digital-to-analog converters -- all separate and all optimized for specific applications. The benefit? It’s simple -- better sound!

We’ve included only one input marked "AC-3 RF" because only laserdiscs need the additional circuitry and it’s highly unlikely that you’d have two laserdisc players in the same system.

Other Dolby Digital-capable sources (DVD, new model DSS, HDTV, etc.) deliver Dolby Digital signals directly without the need for any modulation/demodulation. That means you can use ANY COAXIAL OR OPTICAL DIGITAL INPUT ON A DENON DOLBY DIGITAL (AC-3) PRODUCT TO CONNECT A DOLBY DIGITAL SOURCE.

Another advantage is that any of these coaxial or optical digital inputs will also accept a standard 2 channel PCM digital signal from, say, a CD player or a MiniDisc player’s digital output. Switching between Dolby Digital and a standard S/PDIF digital signal is automatic.

After you’ve connected your chosen sources to the appropriate inputs, remember to use Denon’s set-up menu to assign a name to each input.. It’ll really reduce confusion and make it easier for you, other family members, or friends to enjoy the full potential of your home entertainment system!

Here’s a little extra information to help you understand why laserdiscs need special handling: A Dolby Digital-encoded audio signal from a laserdisc needs additional processing before a Dolby Digital processor can work its magic. That’s because the laserdisc is a comparatively older format (it first appeared in 1980), and the only way to get a Dolby Digital signal onto the disc was to "modulate" it into the space formerly occupied by the right channel analog signal. (Modulation, by the way, isn’t a new technique: We benefit from it every time we turn on the radio! "FM" and "AM" are simply abbreviations for "Frequency Modulation" and "Amplitude Modulation" respectively.)

Of course, when you modulate a signal to get it onto the disc in the first place, you must demodulate it prior to playback. The "AC-3 RF" input routes the signal through the necessary demodulator and only then sends it to the Dolby Digital processor. AC-3 RF demodulation is a feature of Denon's top A/V receiver and processor models.

DTS-encoded laser discs feature conventional Dolby Surround-compatible analog audio soundtracks, with the area ordinarily used for the PCM (2 channel digital audio) containing the DTS digital signal. You'll need a laser disc player that features a digital output jack to deliver the DTS signal to your processor. This is not the same as the Dolby Digital AC-3 RF jack, which is only used for Dolby Digital-encoded laser discs.

DTS-encoded music discs look like CDs and play in CD players. They must be played in a CD player, laser disc player or a DVD player with the digital (PCM) jack output connected to a DTS encoder (or an A/V receiver or pre-amp that includes DTS decoding).

DTS-encoded DVDs must be played on a newer DVD player that features DTS Digital Output compatibility. Only certain models of DVD players (including Denon models DVD-3000 and DVD-5000) introduced from March 1998 onward have the DTS Digital Output logo on the front panel. This signifies that the player's internal circuitry can retrieve the unique DTS digital information from the DVD and output it to the digital jack(s).

Recently, top Denon A/V receiver and pre-amp/processor models now offer DTS decoding, along with Dolby Digital and Dolby Pro Logic decoding. As well, many Denon A/V models include a 6 Channel Input feature that allows you to connect a DTS (or other surround processor).

For owners of select Denon A/V receiver or pre-amp processor models, DTS decoding can be retrofitted in some cases. The MSB Technology Co. specializes in adding DTS decoding to existing A/V components, and a number of Denon models can be upgraded. They can also add digital outputs (both conventional PCM as well as AC-3 RF types) to many older laser disc players. Contact MSB at 650-747-0400 for information and pricing. MSB warranty applies to the MSB upgrade elements that they install. Therefore, Denon warranty applies to the Denon product, while the MSB warranty applies to their upgrade. MSB can be reached on the web at:  MSB Technology

Home THX standards are aimed at duplicating -- as closely as possible in a home environment -- the soundfield generated in an ideal movie theater. The specifications are also aimed at minimizing gross system-to-system differences that might alter a soundtrack’s impact.

Home THX standards concentrate on proper spatialization (a soundtrack’s "image" or dimensionality), localization (where a particular sound appears to come from), dynamics (so you can shudder at bomb blasts as well as whispered threats!), and intelligibility (so you can understand all the dialog, for example, even in the middle of that explosion).

Home THX is not a Dolby competitor. THX technologies begin to work only after Dolby delivers a multi-channel signal for additional processing.

For example, Dolby Pro Logic is an analog matrix technique that delivers only a monophonic surround signal: Even though you hear "them" from different speakers, all rear channel information is identical. To increase the apparent spaciousness of this mono signal, THX Decorrelation® circuits shift relative inter-channel phase to decrease any sense of directionality. That’s important in keeping our focus on the screen in front of us. Rear channel information is primarily ambient (or diffused) in nature. It supports the story being presented and shouldn’t distract us with strong aural clues originating from specific points behind us.

Dolby Digital, among its other attributes, delivers totally separate information to Left and Right Surround channels. Some film directors and sound engineers use this capability to create a realistic sense of spaciousness that THX Decorrelation might accidentally alter. For that reason, THX developed Adaptive Decorrelation that continuously monitors incoming signals and initiates decorrelation only when a mono signal appears at the surround outputs of a processor. This preserves all the directional clues intended by movie makers when they’re delivered by a discrete digital "pipeline" and also allows more natural reproduction of older soundtracks that were originally mixed with a mono surround signal.

After you’ve calibrated your system, any difference in Inter-channel levels will be totally controlled by the audio signal from the software you’re playing, and not influenced by some room-specific or system-specific artifact.

That’s why all surround systems give you some way of adjusting relative levels for each channel individually so that they all sound equally loud at your ears. In other words, a well-designed surround sound system will let you compensate for different speaker placement and differing speaker efficiencies. After you’ve done this, you can use the master volume control to change overall system level without affecting critical channel-to-channel relationships.

After you’ve placed all the speakers in your surround system in the best place (sometimes a somewhat trying task in itself!), you’ll need to calibrate the system by adjusting each channel’s level (or "trim") control individually. Although most Owner’s Manuals state that you can do this by ear, we recommend that you use a sound level meter for real accuracy. Don’t worry, these gadgets are not expensive or difficult to use. (Radio Shack’s most affordable meter -- catalog # 33-2050 -- will set you back only a bit over $30 and it’s perfectly adequate for the job. Besides, you can use it to impress your friends after you’ve calibrated your system!)

Although unit-by-unit differences exist (please read the instruction manual!), here’s a brief overview of the calibration process:

1) Set your sound level meter to "C" weighting. Don’t worry about other scales for now -- the "C" scale is the best match for the way we hear. Select "Slow" response -- "Fast" doesn’t give as clear a picture of the average sound level and we’re looking for average readings for best accuracy. Set the Range selector at "70."

2) Place the sound level meter as close to where your ears will be when you’re in your favorite listening/viewing position. This means you should hold it at ear height but as far away from anything -- especially your body -- that might reflect sound into the meter’s microphone and upset the reading. (The Radio Shack meter, by the way, has a threaded socket to accept a camera tripod screw.)

3) Turn on the test tone signal (every unit has one!.) Denon units will automatically set the volume to a medium level and some models will indicate the reference level: "00" by the volume control.

4) Begin calibration by adjusting each channel so that it’s relative output produces a reading of 75 dB on the meter. (You may feel more comfortable setting the meter’s Range to 80 and then reading down from there to 75. It’s up to you.

You’ll probably have to cycle through all channels several times until you’ve got the same reading on the meter for each channel. Don’t worry -- just take your time and exercise a little patience. Remember, once you’ve done this once, you won’t have to do it again!

To understand this a bit better, first realize that all amplifiers are designed to deliver a signal into an electrical "load" or resistance presented by the loudspeaker. We measure resistance in units called "ohms" (after the German physicist Georg Simon Ohm, 1787–1854).

Conventional wisdom makes an 8 ohm loudspeaker load the most acceptable because it "protects" the amplifier from delivering too much current. A 4 ohm loudspeaker can encourage a marginally designed amplifier to deliver more current than it comfortably can.

However, you should remember that a loudspeaker’s impedance rating is a nominal or average one: A speaker rated at 8 ohms may actually vary from 5 (sometimes even less) to 20 ohms or higher, depending on the frequency at which you measure the impedance. (Don’t worry about this too much -- good speaker engineers are well aware of these variations and take them into consideration when designing products.)

In general, you’ll find that Denon products are designed to function with a wide variety of loudspeakers and have power supplies and output circuitry more than able to meet the current demands of low impedance loads.

In the rare event that very low impedances tax the amplifier, quick acting circuitry will protect it from damage. If unusual operating conditions trigger this circuitry, the word "PROTECTION" will appear on the unit’s front panel. If this happens, simply turn the unit off, wait a moment or two, and turn the unit back on again. The protection circuitry will automatically reset. If it re-engages, check your system for possible malfunctions.

Traditionally speaking, bi-amping means the use of two separate amplifier channels connected directly (no passive crossover in the signal path at all!) to individual loudspeaker drivers optimized to reproduce a particular frequency range. For example, one amplifier channel would be connected directly to a tweeter for high frequency reproduction, another to a woofer for bass reproduction.

Bi-amping requires an electronic crossover to divide the wide range audio signal from a preamplifier before that signal ever gets to the amplifiers. The advantages of traditional bi-amping are significant. Damping factor (a measure of the amplifier’s ability to control the back-and-forth motion of the driver) increases, intermodulation distortion goes down, and effective amplifier power is increased dramatically.

Bi-wiring refers to separate wire runs from a common amplifier output to two different inputs on the same speaker. This requires a speaker specifically designed with bi-wiring in mind as the speaker’s passive crossover must be designed to allow this. And the speakers must have two sets of external binding posts connected by removable jumpers or "bus bars."

In ordinary use, you simply leave the jumpers in place and connect the amplifier to either set of binding posts with a single run of dual-conductor speaker cable. For bi-wired operation, simply remove the jumpers and connect each set of binding posts to the same amplifier channel with separate runs of speaker cable. (Many manufacturers make special "bi-wire" speaker cables that reduce bi-wiring’s visual intrusion by jacketing four conductors in one larger cable.) Bi-wiring’s advantages are generally considered to be more subtle than bi-amping and center around better control of back EMF (electromotive force) from the speaker drivers and increased definition. However, remember that conventional bi-wiring is also much less expensive to implement than bi-amping as it does not require separate amplifiers or electronic crossovers.

The confusion between bi-amping and bi-wiring arose when audiophiles began connecting different legs of a bi-wireable loudspeaker’s passive crossover to different amplifiers or different channels of the same amplifier. Notice that, like conventional bi-wiring, no electronic crossover is used so both amplifier channels are being fed the same full range signal. The "improvements" resulting from this connection scheme, especially when compared to simple bi-wiring, are even more subtle indeed as the signal must still pass through the loudspeaker’s passive crossover.

This is one case where we think tradition wins. Bi-amping, as we’ll use the term on our Website, will refer to those instances where an electronic crossover divides a wide range audio signal and then sends it to two separate amplifier channels that are, in turn, connected directly to the voice coils of drivers reproducing a specific range of frequencies.

We’ll use the term bi-wiring whenever the output of a single wide range amplifier channel is connected to two sets of loudspeaker binding posts which are, in turn, connected to different sections of a passive crossover located between the amp’s output and the drivers’ voice coils.

For those who can’t leave well enough alone, we’ll use "bi-amping/bi-wiring" whenever a full range signal goes through two separate amplifier channels before it hits a loudspeaker’s binding post sets. But we’ll use it infrequently as we don’t think there’s a lot of real musical value in that approach.

Remember that some Denon products make bi-wiring easier by providing two sets of output terminals from a single amplifier channel. This means you don’t need special "bi-wire cable" to enjoy the advantages -- just use two runs of your regular speaker cable (make sure they’re the same length) to enjoy the benefits.

If you experience some unusual behavior -- a channel that’s suddenly silent, "forgotten" level adjustments, some eccentricities in your unit’s Personal Memory Plus system, etc. -- you may need to reset the microprocessor. Of course, you should check all connections carefully first. But if you’ve eliminated these items as a source of potential problems, you may need to go through the initialization process.)

Initialization is easy. For the AVR-3600 and AVR-5600 receivers, for example, just turn the unit off with the front panel power switch. Then press and hold both the "AC-3 RF" and "Phono" simultaneously while you turn the unit back on. (Use the same front panel power switch.) That’s all that’s involved.

What causes these problems? Several things can -- a jolt of static electricity, a current surge through an antenna input, etc. But don’t worry, the microprocessor is well shielded from any permanent effects.

When you do initialize the microprocessor, remember that this erases any setup instructions you may have previously programmed into the unit. However, the on-screen menu will quickly get you through a new setup. And, if you write down your preferred settings BEFORE you reset your unit’s microprocessor, you’ll have an even easier job!

You can use the digital compressor (called "D. Comp." on Denon products) whenever you’re listening to a Dolby Digital source. It’s a truly useful feature we’ve included on many of our Dolby Digital-capable products.

D. Comp. circuitry progressively reduces the dynamic range (the difference in loudness between very soft and very loud sounds) of any Dolby Digital source. Denon products give you four different D. Comp. settings (Off, Low, Mid, and High) to match specific needs. "Low" provides the least compression, Mid contributes moderate compression while "High" really stomps on dynamic range with a maximum peak reduction of 15 dB and a 10 dB upwards expansion of very soft sounds -- that’s a maximum 25 dB reduction of dynamic range. .

You’ll find D. Comp. Circuitry particularly useful while watching an action movie late at night when the kids are asleep in the next room. By compressing the sound track’s dynamic range, you’ll be able to hear soft dialog without blasting yourself out of the chair when explosive sound effects appear.

Experiment with different D. Comp levels to find the one that’s best for your needs. We recommend that you use the least amount of compression to preserve the source’s natural dynamic range but the final choice is up to you! Enjoy.

Dialog Normalization, on the other hand, helps you avoid the "this one’s too loud, this one’s too soft" level differences often encountered when changing inputs or sources. Dialog Normalization, which takes its clues from information embedded in the digital audio data stream, makes sure everything’s "just right" -- that levels are roughly the same as you switch sources.

Re-equalization, part of THX’s collection of technologies, is a specially-contoured "shelving filter" that gently adjusts the extreme high frequency range of the front chanels, to compensate for the fact that many film soundtracks mixed for theatrical conditions sound very bright when played in a home environment. Whenever you select THX processing for a Dolby Pro Logic or Dolby Digital source, THX Re-equalization circuitry is automatically activated and contours the sound for proper reproduction in the typical home theater room.

Denon’s "Cinema EQ," actually developed as a "stand alone" solution to overly-bright soundtracks before THX put its bundled technologies together, approaches the excessive high frequency problem from a different perspective. The "Cinema EQ" circuit has a progressively greater effect on frequencies further away from the "corner frequency" (the point where the filter begins to operate).

Here’s why.

When you press the remote control’s "On Screen" button, the on-screen menu appears. Most times, you’ll probably want to page through the menu to look for a particular setting and subsequent pushes of the "On Screen" button make that easy -- every time you press it, you find yourself looking at a new menu page.

However, there may be times when you just want to check the menu’s first page and it’s annoying to have to scroll through all the menu’s pages just to get to the end. To avoid this, just press the remote’s "Mute" button and the menu will disappear! However, you’re now in mute mode so you need to press the "Mute" button once more to restore your previous volume setting.

Easy, wasn’t it?

Here’s the story. .

THX circuitry operates only when you’ve already selected Dolby Pro Logic or Dolby Digital processing. As you know, these Dolby-developed multi-channel techniques contain very precise directional clues so that a decoder will correctly place certain sounds in the center, in the rear, etc. If your source was not recorded specifically for Dolby playback and you use a Dolby decoder anyway, there’s almost no chance of hearing what the artist intended you to hear. So why bother? And, as we’ve said, you can’t use THX if you’re not already using Dolby processing.

But what about music CDs recorded specifically for Dolby playback? Even here, THX may not be desirable. Remember that THX Re-Equalization®, an essential part of THX processing, is designed to reduce front channel high frequency response to make movie soundtracks more listenable. But if the music on a Dolby-encoded disc was recorded without a movie soundtrack’s emphasized high frequency content, THX processing will make it sound comparatively dull. Not an ideal situation, is it?

Two further notes:

There’s a big difference between a movie soundtrack and a CD containing music from that same soundtrack. Although THX may enhance your enjoyment of the soundtrack itself, it won’t (for reasons we’ve already outlined) help you much with the music CD.

Made-for-TV movies, even those with a Dolby Surround soundtrack, usually don’t have the emphasized high frequency content typical of films intended for theatrical release. So THX processing will probably diminish high frequency content by an unacceptable degree. On the other hand, most theatrically-released movies, even when they’re shown on TV, might well benefit from THX playback. You’ll have to make this call yourself but if you know that a particular movie is being broadcast with a surround audio signal, give THX a try.

The "Protection" light comes on when the receiver’s current sensing and thermal monitors detect some unusual operating condition that, if left unchecked, might damage the amplifier. The sensors disconnect the amplifier from the speakers by switching the high speed output relays "off." This can happen, for example, if there’s a dead short in a speaker wire, or if you’re using very low impedance loudspeakers at high volume for an extended length of time.

In most cases, the circuitry will automatically reset after a few moments and the Protection indicator will go out.

If the Protection indicator does not go out, or if it goes on immediately after you turn on the receiver check your loudspeaker connections to make sure no wires have inadvertently shorted.

If, after checking all your connections, the Protection indicator stays lighted, you may need to "initialize the microprocessor" (see the FAQ on that topic) or take your receiver to an authorized repair center for a checkup. Run through the reinitializing process first -- it’s easy to do at home without disconnecting the entire system.

We chose each "effects" parameter to heighten the sensation of being in a particular acoustic space. If you generally prefer "Jazz" rather than "Classic Concert" mode, by all means use it. Remember, we’ve included these modes to make your listening more enjoyable and less difficult. Your taste is paramount here. So have fun.

The fact is that all DSP (Digital Signal Processing) modes will change the timbre and tonal balance of the music to some degree. If you’re a purist yet still want the benefit of using all the speakers of your home entertainment system, we strongly suggest that you consider Denon’s exclusive 5 CHANNEL STEREO mode for music enjoyment.

5 CHANNEL STEREO adds no processing whatsoever to the audio signal. Left channel information comes from both Left Front and Left Rear speakers. You’ll hear unaltered right channel information from both Right Front and Right Rear speakers. A mono signal (L+R) feeds your center channel speaker.

That way, every speaker contributes to your enjoyment and no unwanted artificial processing detracts from the musical nuances you enjoy so much. We think you’ll like it.