XLR & Mic Splitters: How Well Do They Work? (Full Guide)

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Perhaps you want to send an audio signal from one source to multiple destinations. Or maybe you want to split a microphone signal and then send one of the signals to the Front of House mixing engineer while recording the same signal. 

Whatever your reason, XLR splitters can come in quite handy when you want to duplicate a signal and send it to multiple devices. But how effective are they? Do XLR splitters work?

XLR splitters certainly work. They are designed to take an audio signal from a single source and then route the same signal through two or more XLR connectors so that the audio signal can be transmitted to multiple locations. 

Although XLR splitters work, there are certain things you need to know if you want to use them without any issues. There are many different types, and each has its own limitations. And this article will help you choose the right type of XLR splitter for your needs. Let’s get into it.

How Do XLR Splitters Work?

XLR splitters are used in many pro audio applications for recording sessions, live applications, broadcasting, and audio monitoring. They are used by professionals to distribute an input signal into various output signals.

XLR splitters work by splitting and sending one audio signal into two or more destinations. In its simplest form, two or more XLR connectors are connected in parallel to a single XLR connector. This means multiple XLR connectors share the same audio signal from one source.

Check out the wiring diagram of a basic XLR splitter.

In its simplest form, here is how a basic XLR splitter cable is wired. Two XLR ports are connected in parallel to one XLR port. Meaning, two XLR receive the same signal from one XLR port.

When you connect the single XLR end of an XLR splitter to an audio source, it will essentially route that same signal through the double XLR end of the XLR splitter. 

There are many different ways people use XLR splitters. Commonly, they are usually used at larger venues to provide audio feeds to both a monitor desk or a front-of-house mixing desk. This allows the monitor mix to be different from the house mix so that the musicians can hear a mix with certain instruments emphasized.

Types of XLR Splitters

Passive XLR Splitters

Passive microphone splitters are splitters that can split a sound signal into two or three components or destinations without requiring any external power. And there are two main types of passive splitters.

1. XLR Parallel Splitter (Y-Adapter Splitter)

This is commonly known as a Y-adapter or Y-cable splitter. The XLR Y-splitter is the traditional form of XLR splitter and the most popular type of XLR splitter available on the market. This is because they are much simpler to make compared to other types of splitters. Y-adapter splitters are designed to take one signal and split it into only two separate signals.

It is composed of simple parallel wiring of a 3-pin female input XLR to two male XLR outputs. In a parallel splitter, the outputs are connected in parallel with no isolation between outputs.

XLR Y-adapter cables are ideal for splitting line-level signals. These are signals from a digital piano or keyboard, mic preamp outputs, mixing console outputs, and more. These are fairly strong signals that a passive XLR Y splitter can split with less to no issues at all.

They are, however, not ideal for splitting signals directly from a microphone. That’s because the signal that comes out directly from a microphone is a very weak signal known as a mic-level signal. 

And attempting to split a microphone signal with a passive XLR Y-adapter will lead to signal dropouts, which will reduce the audio quality and the loudness of the final audio output.

Also, Y-cables can introduce all sorts of impedance, ground loop problems during live situations when you use an XLR Y-cable for splitting.

Passive Transformer-Isolated Splitter

Passive Transformer-Isolated Splitter is an attempt to solve some of the problems of an XLR Y-splitter. It’s a very popular option among sound engineers and technicians. This is because using them prevents extra impedance and ground loops issues that may affect your sound quality. 

For those who don’t know what ground loop issues are, I recommend you keep reading because I will touch on them later in this article.

Passive isolation transformers can be used when there is the need to take a single microphone signal and send it to multiple destinations. 

Here is how it works.

One of the outputs of this splitter is wired directly to the input like a traditional XLR cable. And on the second output is a transformer. This transformer essentially prevents any ground loop issues that may arise. It also prevents any impedance change that may occur with using a traditional Y-cable.

These splitters usually come in either 2-way split or 3-way split models. A 3-way split passive transformer splitter has a single input and three outputs. This means it is designed to take a single input and send it to three different destinations. A 2-way split model, on the other hand, takes a single input and sends it to 2 different destinations.

Transformer isolated splitters are ideal for splitting microphone signals without any issues.

Something you should know, however, is, transformer-isolated splitters are more expensive than XLR Y-splitters. However, they are a much better alternative to XLR Y-splitters. And if you’re using them for professional purposes, then they are definitely worth the investment. 

Active XLR Splitters

Just like active speakers, active XLR splitters are microphone splitters that require a power source in order to work. 

Here is how active microphone splitters work.

The input of the splitter feeds into a mic preamp. The mic preamp then boosts the signal into a line-level signal. And then, the output of that mic preamp, which is a line output, is transmitted to feed the multiple outputs of the splitter.

Active splitters require power to work because of the built-in mic preamp. And they usually have more outputs than passive XLR splitters. They will usually have four or more outputs, making it possible to send one signal to multiple destinations.

Most of them also come with onboard features such as metering, adjustable gain, compressors, and high-pass filters.

Some active microphone splitters also come with an integrated regulator for protection against power supply fluctuations. An active microphone splitter must be used if you have to connect one microphone to multiple inputs simultaneously. 

This is because active microphone splitters help to preserve the loading and powering conditions for the microphone and to prevent interference.

They are the most reliable option of all the different types of splitters we have discussed. However, they are quite expensive too. And it will probably out of the budget of most people.

Potential Problems with Using Microphone Splitters

Low Output Level of Signals

Using XLR splitters, specifically, XLR Y-splitters can lead to a reduction in the output level of your final signal. This is a result of a loss in the initial signal strength from the microphone that enters the splitter.  

XLR Y-splitters are known to introduce a small amount of signal loss to sound because the initial signal that comes from the microphone is weak. This weak signal is then divided into fractions and sent to different devices. This results in a weak or low-level output signal that is quieter than the original.

However, this signal loss here does not mean a reduction in the quality of sound but rather, reduction in the level of amplification.

When an audio signal is split passively, a sound reduction will usually be noticed in the signal strength. As I’ve already mentioned, this is usually noticeable when a Y-splitter cable is used.

Headroom and Transient Distortion

In Pro Audio, headroom refers to the ratio of the maximum level of undistorted signal a system can handle compared to the normal level for which the system is designed to contain. Headroom provides a form of a safety zone to accommodate further amplification, unexpected loud sounds, or transients without the risk of clipping or damaging the audio signal.

Because microphone splitters cause the signal strength of your outputs to reduce, you are likely to increase the level of amplification in your setup. Increasing the level of amplification significantly might cause you to run out of headroom.

When you run out of headroom, your sound gets distorted. This means, when you have more headroom, you don’t need to worry about transient peaks causing clipping distortion.

Distortion is usually prevalent in XLR splitter connections. For XLR microphone splitters, the difference in impedance of the two consoles the cable has been connected to can make your system more prone to distortion. Outside interference can also introduce hums and buzzes into your setup when using XLR splitters.

Ground Loop Issues

This is a common source of noise in an audio system. This problem usually occurs when each output is connected to a system with a different ground potential. It is a well-known fact that when two different audio devices are plugged in, their actual resistance to the ground varies.

Due to this variation, when the first console identifies a lower resistance to ground through its connection through a splitter to the second console, some portion of its AC ground return current will take this part of least resistance.

The chassis of different devices powered from different outlets sometimes have different ground potentials. This results in a hum problem being introduced into your sound. You can solve this ground loop issue when it arises by getting a ground loop isolator.

Which XLR Splitter Should You Choose?

Based on everything we have talked about, here is how to choose the suitable XLR splitter for your needs.

  • Use XLR Y-Splitter only for line-level signals. This is the audio signal that has gone through the preamplification stage. And it’s a strong audio signal. Line level signals are signals from a preamplifier output, digital keyboard or synthesizer, mixing console output, MP3 player and more. You can split these signals with a Y-splitter without any issues. Don’t use an XLR Y-Splitter to directly split a microphone signal.
  • Use a Transformer Isolated Mic Splitter for mic, instrument and line-level signals. Transformer isolated splitters are good for all types of signals. You can plug a microphone or guitar into them directly and split their audio signal without any signal loss or change in impedance. And most of them have a ground loop switch to help prevent ground loop issues.
  • Use an Active Mic Splitter to split signals to many destinations. If you are looking to split one audio signal to, let’s say, four or more destinations, an active mic splitter is definitely the best option to go for. However, there are other transformer isolated splitters that allow you to do this as well.

Best XLR & Mic Splitters

ART S8 8-Channel Mic Splitter

The ART S8 8-Channel Mic Splitter (on Amazon), just as the name depicts, allows you to connect eight different microphones or instruments to the device at the same time. And it splits each channel into two. It’s a transformer-isolated splitter, so it requires no external power to work.

This allows you to send one of the two outputs to the Front of House mixing engineer and the other output to a monitor mix engineer or to an audio interface for recording purposes.

It also has a 29dB pad button per channel for attenuating any high-level signal being sent to the splitter. And then there is a ground lift button as well per channel to help you avoid ground loop issues.

The ART S8 Mic Splitter is suitable for live use as well for the studio. And in my opinion, definitely worth the investment if you are a professional.

TISINO XLR Y-Splitter Cable

This is a simple XLR Y-Splitter Cable (also on Amazon) that easily gets the job done. The input is 1 Male XLR connector that splits into two female XLR connectors as outputs.

One thing I particularly like about this Y-splitter cable is that it has locking-XLR connectors. This prevents any accidental pullouts. The cables are also rock-solid, made from heavy-duty elastic rubber. This means they will last for a long time before they ever show any signs of damage.

Do Microphone Splitters Reduce Sound Quality?

In general, XLR splitters do not reduce the quality of sound output from your device. However, using cheap and inferior splitters might cause your audio signal quality to actually reduce. XLR splitters are designed to split analog signals into two or more signals without interfering with the signal quality.

The main aim of XLR splitters is to route the audio signal that passes through them without compromising on sound quality. This means it is safe to split the output of a microphone to other devices without experiencing a visible drop or difference in the level of sound quality experienced.

When you use a splitter, you are simply adding more wire to the signal path. This will introduce more resistance to your audio path, hence requiring you to increase the amplification of your system. However, this increased resistance will not cause any visible reduction in the sound quality.

If your microphone splitter causes your sound quality to reduce, it can be attributed to the quality of the splitter being used. I advise that you invest in high-quality splitters to avoid sound quality reduction.

Conclusion

XLR splitters work. They are ideal for situations where you need to split your microphone or any other audio signal and feed more than one mixing console or provide a separate mix for recording or broadcasting performances.