Some components that still provide analog audio-only or digital and analog audio connectivity include:
CD playersAudio-tape decksVCRsOlder DVD and Blu-ray Disc players
As a result, many home theater receivers still provide some analog audio connection options—usually analog stereo inputs and outputs, a subwoofer, and Zone 2 preamp outputs. Multichannel analog inputs and outputs are sometimes provided.
What Are Multichannel Analog Connections?
Multichannel analog connections consist of a separate audio connection for each channel of audio. Just as there are left-channel and right-channel analog audio connections for stereo, separate analog audio connections for the center, left and right surround, and, in some cases, left and right surround back channels are possible. All these connections use RCA jacks and cables.
Multichannel Preamp Outputs: Home Theater Receivers
The most common multichannel analog connections found on mid- and high-end home theater receivers and AV preamp/processors are preamp outputs. These outputs connect a home theater receiver or AV preamp/processor to external amplifiers. This allows access to all the audio features of a home theater receiver. If onboard amplifiers aren’t powerful enough for a setup, the preamp outputs allow connection to more powerful external power amplifiers for one or more available channels. When multichannel analog preamp outputs are used, they disable the home theater receiver’s internal amplifiers that are designated for the corresponding channels. This means you cannot combine the power output of an internal amplifier with an external amplifier for the same channel. Some home theater receivers allow reassignment of internal amplifiers to other channels that aren’t being bypassed. You may be able to use a mix of internal and external amplifiers to expand the number of channels that a home theater receiver can control.
Multichannel Preamp Outputs: AV Processors
Multichannel analog preamp outputs are optional on home theater receivers but required on AV preamp processors. That’s because AV preamp processors don’t have the built-in amplifiers required to power speakers. To get audio signals to speakers, analog preamp outputs enable connection to external power amplifiers. The amplifiers, in turn, power the speakers.
Multichannel Analog Preamp Outputs: DVD and Blu-ray Disc Players
Before the introduction of HDMI, some high-end DVD players and a few Blu-ray Disc players offered a multichannel analog preamp output option. Some still do. These connections support two capabilities:
The player can decode Dolby Digital and DTS surround-sound audio formats internally. The signal then passes to an older home theater receiver that lacks built-in Dolby Digital/DTS decoding capability and has no digital optical/coaxial or HDMI inputs. It may also provide a set of multichannel analog audio inputs. When this option is used, the home theater receiver displays either Direct or PCM on the front panel instead of Dolby or DTS. You still get the benefits of those formats because they were decoded before they reached the receiver. It can support SACD and DVD-Audio. These audio formats, introduced in 1999/2000, affect audio connectivity, even if the home theater receiver has built-in Dolby/DTS decoding and provides digital optical/coaxial and HDMI inputs.
Due to bandwidth requirements, the SACD and DVD-Audio formats can’t use digital optical or digital coaxial audio connections. This meant that, before HDMI, the only way to transfer those audio signals to a home theater receiver was via the multichannel analog audio connection option.
Multichannel Analog Inputs
Before HDMI arrived, multichannel analog audio input connections were common on home theater receivers and AV preamp/processors, but they are now rare. With a home theater receiver or AV processor that offers this option, you have the flexibility to use a DVD, Blu-ray Disc player, or another source component that offers this as an output connection option. Multichannel analog inputs are discrete connections. If you connect a two-channel stereo analog source such as a CD player, you need to use only the front left and right channel inputs. For full 5.1 or 7.1 channel surround sound, you need to use all the inputs and connect the corresponding designated channel outputs from the source component to the correctly designated channel inputs. If you connect the analog front left/right preamp outputs of the source device to the surround left/right analog inputs, the sound comes out of the surround speakers instead of the main left/right speakers. If the source component has a subwoofer preamp output, it must be connected to a receiver’s subwoofer preamp input so it can be routed to the receiver’s subwoofer output. You could also bypass that option and connect the subwoofer output from the source device directly to the subwoofer.
Know Your Audio Connection Options
There are several home theater connection options. New options like HDMI have been introduced while old options are being phased out. Others have been consolidated, such as shared analog video inputs on newer TVs. People have a mix of old and new components that need to be connected, and multichannel analog audio connections are an option that may sometimes be available.
