How to Daisy Chain AV Equipment

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As an IT professional, you may one day be called upon to hook up AV equipment in the office conference room or install speakers in an auditorium for a presentation from the CEO. Or maybe a staff member needs multiple monitors on their desk, and it’s up to you to make it happen.

But what if you run into a situation where the source component doesn’t have enough outputs to make the connections you need? You may be asked to connect eight speakers, for example, but the soundboard only has four outputs. You don’t want to risk your reputation as a technical guru, but you don’t have a selector switch or other device you need to make the connections happen.

The answer? It may be possible to make those connections via a daisy chain.


HOW TO DAISY CHAIN A CONFERENCE ROOM AV SETUP

Before we begin, it’s important to understand the meaning of the term “daisy chain.” Simply put, unlike a scenario where each peripheral component is connected directly to the source component, a daisy chain is a method of connecting peripheral components to the source component in a string. This may form a ring with the last component’s output going back to the first input, or it may terminate with the last device on the chain.

In addition to allowing multiple peripherals to connect to a single source output, daisy-chaining electrical components can allow for a more organized, less cluttered installation.

Consider a situation, for example, where you need to connect an audio/video source such as a DVR, Blu-ray player, or a DVD player to a receiver or amplifier and a flat-panel display in the office conference room. Although it’s possible to run one connection to the receiver for the audio signal and another connection to the display for the video signal, it can quickly become a tangled nest of cables that look sloppy and unprofessional.

Instead (assuming each component has HDMI inputs and outputs), a more straightforward way would be to connect the video component to the receiver via an HDMI input, then connect the receiver to the display via another HDMI cable. The receiver will process the audio signal and direct it to the speakers, passing the video signal to the display.

One drawback to this type of daisy chain connection is that it requires the receiver to be on when playing video content. Check the receiver’s manual for a setting that allows for both the audio and video signal to be passed to the display, allowing you to use the display’s speakers for audio for those situations where you don’t need a great deal of volume.


HOW TO DAISY CHAIN SPEAKERS

A situation may arise where you need to connect multiple pairs of speakers to a single amplifier, receiver, or soundboard, but there aren’t enough outputs to handle the task. It might be a scenario where the room is very large and you want to place speakers throughout, or you want to place speakers in separate rooms.

The easiest way to accomplish the task is by using a speaker selector switch that splits a single set of speaker outputs into multiple outputs. Still, it may be the case that you don’t have the time or funds to purchase a switch, but you still need to make the connection.

An important note: In most cases, it’s not advisable to daisy chain more than two pairs of speakers to a single output. Doing so could end up damaging the equipment.

The simplest way to make the connection is to connect the first speaker to the source component, as usual, then connect the next speaker to the first one, matching plus to plus and minus to minus. Although this type of connection is what people often consider a daisy chain, in fact, the speakers are wired in parallel. The effect is the same as wiring each speaker directly to the output.

In addition, be aware that the speakers’ total impedance load decreases when wiring speakers in parallel. Speakers are typically rated at 4 ohms, 6 ohms or 8 ohms. Connecting two 8-ohm speakers in parallel, then, would result in a total impedance of 4 ohms. Most amplifiers are designed to have a total load impedance of 4 ohms or higher, but not lower than 4 ohms. Connecting more than two speakers to each output would result in an impedance load of less than 4 ohms, increasing the amplifier’s power output and creating the potential for damage.  

Multiple speakers can also be wired to a single output in series. Using this method, you would connect the plus output of the amplifier to the plus connection of the first speaker. The minus connection of that speaker is then connected to the plus connection of the second speaker, and so on. The minus connection of the final speaker in the series would then be connected back to the amplifier’s minus output.

Connecting speakers in series has its drawbacks as well. Unlike connecting speakers in parallel, connection them in series actually increases the impedance load, so connecting two 8-ohm speakers in series results in an overall impedance load of 16 ohms. Although this is safer than wiring speakers in parallel, increasing the impedance load reduces the amplifier’s power output, resulting in reduced volume. In addition, if a single speaker wire is disconnected, the entire chain will go out.

It is possible to connect speakers in a combination of series and parallel to maintain the impedance load. Unfortunately, doing so will result in the rat’s nest of wires you were hoping to avoid with a daisy chain connection in the first place.


HOW TO DAISY CHAIN MONITORS

Of the various types of AV components to daisy chain, probably the easiest are computer monitors. At the same time, though, daisy chaining monitors requires that they incorporate DisplayPort 1.2 ports that support DisplayPort 1.2 Multi-Stream Transport (MST) and that the video or graphics card on your PC or laptop supports DisplayPort 1.2 MST.

If your equipment meets the requirements, the rest is simple. Just connect your PC to the DisplayPort In connection on the first monitor using a DisplayPort daisy chain cable, then connect the DisplayPort Out connection on that monitor to the DisplayPort In connection on the second monitor. Follow the same procedure for each additional monitor. For the last monitor in the chain, disable DisplayPort 1.2 mode.

The number of monitors that can be daisy-chained together is limited by the resolution, timings, and refresh rates of those monitors. At a resolution of 2560 x 1600, the maximum is two, while at a resolution of 1680 x 1050, the maximum is five.


DAISY-CHAINING MICROPHONES

In today’s world of global business and remote work, meetings are often held via a Web conferencing service. In a situation where there are many attendees gathered around a large conference table, everyone must be heard clearly. As such, it may be necessary to incorporate multiple microphones.

Fortunately, new products developed by Yamaha make the task easy. Yamaha’s YVC-330 Speakerphone features SoundCap™ technology that eliminates background noise for meetings held in loud, open space environments. The speakerphone’s “Self-volume balancer” automatically adjusts speaker volume appropriately to fit surrounding ambient noise levels. The YVC-330 offers the ability to daisy chain two units for medium-sized spaces.

And Yamaha’s YVC-1000 Unified Communications Microphone and Speaker System is an intuitive unified communications audio solution for medium to large conference spaces that calls for flexible audio, web, or video conferencing.

The YVC-1000 features separate microphone and speaker units that smoothly integrate audio and video for natural, comfortable remote communication. The YVC-1000 enables five distinct microphones to be daisy-chained together via Cat-5 cable for clear communication by all meeting participants. The microphone daisy-chain also allows a wider meeting surface area to be covered for larger meetings and additional participants.

Want to learn more about connecting AV equipment? Check out this article on Bluetooth, or this one about how many microphones can be used simultaneously.