Denon AVR-2309CI 7.1 A/V Receiver


Surround Sound Options

The Denon AVR-2309CI is at the forefront of current AVR technology. It includes decoders for just about every major surround codec available. If you have the good fortune of owning one of the latest Blu-Ray players that can output DTS-HD Master Audio or Dolby TrueHD in their bitstream format over HDMI, then you will see said codec indicators light up on the front panel when using them. There has been considerable debate among home theater enthusiasts as to whether this is even necessary to have in an A/V receiver.

Decoding can be (and is mostly still) done in the player and each channel output as uncompressed PCM, which, when transported via HDMI to a capable receiver, should theoretically be sonically identical to the method mentioned above. Since these codecs are really nothing more than lossless compression techniques (think of the .zip format in the PC world), the “decoders” are really just decompressing the signal. This should mitigate any potential differences in the quality of the decoders, which also supports the argument that it shouldn’t matter where the decompression is done (receiver or player). Still, for traditionalists who cling to the idea that the receiver should handle this responsibility, the 2309CI fits the bill.

Of course, along with the lossless codecs, this receiver can handle all of the other Dolby and DTS lossy surround formats, including the newest such as Dolby Digital Plus and DTS-HD. The surround mode you choose is persistent for each source, which is quite useful if you prefer, say, DTS Neo:6 Music for your CD player, but Dolby Pro-Logic II Cinema for 2-channel audio from your cable box. However, what is somewhat frustrating is that the detailed options for each surround format are universal. For example, if I use Dolby Pro-Logic II Music for both my CD source and XM Radio, but I prefer to have different parameters such as panorama on for one but off for the other, I have to manually change this each time I switch the inputs.

These surround parameters persist for the surround mode rather than the source, which may be frustrating for some potential buyers. Also included is the Neural surround mode. This is a relatively new entry into the surround market. The XM-HD surround channels use Neural technology to encode their signal in surround sound. The manual for the 2309CI suggests this as the intended use for this surround mode, but it works just as well with any 2-channel source. The receiver I own includes Neural’s THX 5.1 format (which I often prefer to standard Dolby Pro-Logic II), so I was actually eager to give this mode a test run. I used a couple of older DVDs that included stereo tracks, such as Sneakers and the Usual Suspects. For the most part, I preferred the Dolby Pro-Logic II mode to the Neural mode. Neural seemed to place too much audio in the rear channels for my taste. Still, it is nice to see an alternative included in this unit.

The 2309CI also includes an array of DSP and direct modes. On the DSP side you have rock arena, jazz club, mono movie (for those classic movie lovers to still get clean monaural audio), video game, matrix, and virtual modes. On the direct side, you have 5/7 channel stereo, standard stereo, direct, and pure audio. The latter’s intent is to bypass all audio processing circuitry to give you the cleanest and supposedly highest quality possible audio out of the receiver. It is a bit strange that it will also shut down the front panel display, but will continue to output video over the HDMI connection to the monitor in this mode.

In the past, when I owned a Denon AVR-3805 and engaged pure direct mode, it would shut down the video portion of the receiver completely. The regular direct mode is intended to output the signal without any audio processing, but keeps the front panel display active. Stereo mode is what I prefer when listening to 2-channel music, as it keeps the original stereo channels intact, but still allows me to apply the crossover settings to get the bass to my subwoofer.