Multichannel Analog Audio Connections: What You Need To Know

There is still room for analog audio connectivity in the digital age

Multi-Channel Analog Audio Inputs and Outputs


Although the emphasis these days is on digital connectivity, home theater has a long tradition of analog audio that harkens from the days of high fidelity and stereo. As a result of this foundation, many components provide analog audio-only or digital and analog audio connectivity; these include CD players, audio tape decks, VCRs, and older DVD and Blu-ray disc players. Most home theater components, though, provide primarily digital connection options, such as HDMI, digital optical, digital coaxial, and USB.

This state of affairs has resulted in many home theater receivers still providing some analog audio connection options —most commonly, analog stereo inputs/outputs, subwoofer, and Zone 2 preamp outputs. Multichannel analog inputs and outputs are sometimes provided.

What Multichannel Analog Connections Are

Multichannel analog connections (whether for input or output) consist of a separate audio connection for each channel of audio. In other words, just as there are left- and right-channel analog audio connections for stereo for certain surround-sound applications, it is possible to include separate analog audio connections for the center, left surround, right surround, and, in some cases, left surround back and right surround back. That's in addition to the left and right analog stereo connections. All these connections use RCA jacks and cables.

Multichannel Preamp Outputs: Home Theater Receivers

The most common multichannel analog connection option, which is found mostly on mid- and high-end home theater receivers and AV preamp/processors, includes what are referred to as multichannel analog audio preamp outputs.

These outputs connect a home theater receiver or AV preamp/processor and external amplifiers. This enables consumers to still access all of the audio and video processing features of a home theater receiver — but if onboard amplifiers are not powerful enough for a newer 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, however, they disable the home theater receiver's internal amplifiers that are designated for the corresponding channels. In other words, you cannot combine the power output of an internal amplifier with an external amplifier for the same channel.

On the other hand, some home theater receivers allow you to reassign those internal amplifiers to other channels that are not being bypassed. This feature allows you to use a mix of internal and external amplifiers to expand the number of channels that a home theater receiver can control.

Read the instruction manual for your specific home theater receiver for details on whether it offers the internal amplifier reassignment option.

Multichannel Preamp Outputs: AV Processors

While multichannel analog preamp outputs are optional on home theater receivers, they are required on AV preamp processors. That's because AV preamp processors do not have the built-in amplifiers that are required to power speakers. So, to get audio signals to speakers, the analog preamp outputs enable connection to an external power amplifier(s) via analog audio preamp outputs. The amplifiers, in turn, are able to power the speakers.

You can also find multichannel preamp outputs on older DVD/Blu-ray disc players, but these days, that includes just a few high-end models.

Multichannel Analog Preamp Outputs: DVD and Blu-ray Disc Players

Before the introduction of HDMI, some high-end DVD players and even 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. In other words, it has no digital optical/coaxial or HDMI inputs. It might provide a set of multichannel analog audio inputs, though. When this option is used, your home theater receiver will display either Direct or PCM on the front panel instead of Dolby or DTS. You are still getting the benefits of those formats, though, because they were decoded before they reached the receiver.
  • It can support SACD and DVD-Audio, two audio formats introduced in 1999/2000 that 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 cannot 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.

To use the multichannel analog preamp outputs on a DVD or Blu-ray disc player that has them, though, you need a corresponding set of inputs on a home theater receiver or AV preamp/processor.

Multichannel Analog Inputs

Before HDMI arrived, multichannel analog audio input connections were very common on home theater receivers and AV preamp/processors, but they are rare these days.

If you do have a home theater receiver or AV processor that offers this option, however, you have the flexibility to use a DVD, Blu-ray disc player, or another source component that offers this as an output connection option.

Keep in mind that multichannel analog inputs are discrete connections. This means that, if you are connecting a two-channel stereo analog source such as 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 your source component to the correctly designated channel inputs.

For example, if you connect the analog front left/right preamp outputs of your source device to the surround left/right analog inputs, the sound will come out of the surround speakers instead of the main left/right speakers. If your source component has a subwoofer preamp output, it must be connected to either a receiver's subwoofer preamp input — so it can be routed to the receiver's subwoofer output — or you can bypass that option and connect the subwoofer output from the source device directly to the subwoofer.

The Bottom Line: Know Your Audio Connection Options

There are a lot of connection options in home theater. Through the years, new options have been introduced, such as HDMI, and old options are phasing out. Others have been consolidated, such as shared analog video inputs on newer TVs. As a result, many consumers have a mixture of old and new components that need to be connected. The multichannel analog audio connection option is one choice that might be available to you.