For most people, a stereo or home theatre system consists of a receiver that audio and video components connect to, along with a set of speakers.
However, if you’re interested in hi-fi (high-fidelity) audio, you may know that there are other possible configurations that offer an enhanced listening experience.
The above example relies on what is called an "integrated amplifier," but some choose to use two separate devices, a preamplifier and a power amplifier, instead. This type of setup is called a separate component system.
Does this pique your curiosity? In this article, our Fillion experts explain what a preamplifier is, what it’s used for, and how to choose the one that will best suit your needs.
What is a preamplifier and what is it used for?
The purpose of a preamplifier is to boost the signal from these sources before transmitting it to a power amplifier. Most have a switch or buttons that allow you to select the source you want to preamplify.
Example of a stereo preamplifier: the Rotel RC-1572
Preamplifiers also provide some sound processing. Depending on the model of preamplifier, you will be able to adjust the output volume, left-right balance and tone using different types of controls.
In some cases, a preamplifier can also play a central role in a multi-room audio setup, with either multi-zone or multi-room wireless audio capability. Some preamplifiers even allow you to stream music from Apple AirPlay or Bluetooth-enabled devices such as smart phones and tablets.
Preamplifiers may also be equipped with a USB port to access compatible digital media content directly from plug-in flash drives or other compatible USB devices.
The difference between preamplifiers and integrated amplifiers
At first glance, preamplifiers and integrated amplifiers appear pretty similar. It's what's inside and behind these devices that really sets them apart.
The main difference is that a preamplifier usually needs to be paired with a second device (a power amplifier) in order to power a speaker system. That’s why many brands of audio equipment produce both types of devices.
Example of a power amplifier: the Rotel RB-1582 MKII
An integrated amplifier can act as both preamplifier and power amplifier. It’s a sort of 2-in-1 device that can be connected directly to a set of speakers, unlike the preamplifier.
That’s why preamplifiers and integrated amplifiers (sometimes called receivers) have different connectors. Both have various inputs and outputs, but integrated amplifiers have speaker outputs, while preamplifiers usually don’t. Rather, preamplifiers have RCA or XLR outputs that are used to transmit the audio signal to a power amplifier that has outputs for speakers.
Although preamplifiers cannot connect to regular speakers without an intermediary device, they can connect directly to amplified speakers.
What are the advantages of a preamplifier/power amplifier system
After reading the information above, you might be wondering why anyone would opt for a preamplifier/power amplifier combo rather than an integrated amplifier or receiver.
Here are some of the advantages of a separate component system.
Higher sound quality due to a better signal-to-noise ratio
In an integrated amplifier, the preamplification and amplification components of the signal are crammed into the same box.
When the preamplifier and power amplifier are separate devices, there is more freedom to design the electronic circuits in a way that makes the signal paths shorter.
Additionally, the sensitive low-voltage preamplification circuits are not as close to the high-voltage amplifier components, and the preamplifier and amplifier don’t have to share the same power supply. Finally, some preamplifiers have XLR output connectors, which are even quieter than RCA outputs.
All of these factors help reduce the interference that can create background noise.
With a separate component system, you have more options. You get to choose two devices instead of one, meaning that you can create a setup that is more precisely tailored to your needs. You don’t have to make any compromises.
Do you need as many inputs as possible? How about Bluetooth connectivity? You can choose your preamplifier based on these factors. If you need more output power, opt for a power amplifier that puts out more than 300 watts.
And if your requirements change, having a preamp/power amp system means you can just replace the device that no longer meets your needs rather than having to update the entire system.
How to choose the right preamplifier
If you want to buy a preamplifier, you should take the time to check out a variety of models and manufacturers and compare their characteristics.
Check the device’s inputs and outputs
When choosing a preamplifier, check which types (HDMI, phono, RCA, USB, coaxial, XLR, etc.) of inputs and outputs the device has and how many there are.
The back of a stereo preamplifier equipped with a variety of connectors
For example, if you just want a device you can use to listen to music, you don’t need a preamplifier that has HDMI inputs and outputs. If you want to set up a home theatre system, however, HDMI will be essential.
If you want to use a turntable, you’ll need to find a preamplifier that has a phono connector, which is specifically designed to handle the signal transmitted by this type of device.
As for the number of inputs and outputs, it’s best to choose a device that has enough connectors that you won’t need to constantly switch them around when you change sources.
Figure out which features you really need
As mentioned above, preamplifiers can have a variety of features, such as equalization, Bluetooth connectivity and compatibility with applications like Apple Airplay and Google Chromecast.
Since additional features make for more expensive preamplifiers, you should choose a device that has features you will actually use.
For home theatre systems, you don’t need to choose a preamplifier that supports up to 15.4 channels if your goal is to create a 5.1 system.
Make sure you choose a preamplifier that is compatible with your power amplifier
Since preamplifiers are designed to be connected to a power amplifier, it’s important to make sure the two devices are compatible.
One of the things to watch for is the preamplifier’s output impedance, which is usually measured in ohms.
Set a budget
Like many types of audio equipment, preamplifiers come in a wide variety of quality levels. That’s why the price can range from a few hundred to several thousand dollars.
The price is based on the quality of the device’s components, the precision of the settings, the electrical insulation and the way the housing is built, among other things.
Remember that it may be worth paying a little more for a hi-fi model, since the quality of the preamplifier will directly affect the sound quality of your stereo or home theatre system.
Find out more about preamplifiers from the experts at Fillion
We hope this article has given you a better understanding of preamplifiers. People are often unaware of what they’re used for and get them confused with receivers, power amplifiers and integrated amplifiers.
If you need advice or want help choosing a preamplifier, our Fillion experts can provide personalized guidance and suggest products that meet your needs and budget. Don’t hesitate to contact us or stop by our store for a hassle-free shopping experience. We can even install your stereo or home theatre system!