You might have heard the terms “preamp” and “amp” tossed around and asked yourself – what’s the difference?
Or maybe you’re on the lookout for essential equipment for your home studio and you’re figuring out what gear to invest in.
Whatever the case might be, here is a simple guide to understanding the differences between “amp” and “preamp.”
Summary: Preamp vs Amp
Here’s the difference between an amplifier and a preamp:
An amplifier or amp is a piece of equipment that increases the amplitude of a signal. In even simpler terms, it gives the signal enough “juice” to blast through speakers.
A preamp boosts the signal to line-level (nominal signal level) for the amp to “amplify” it, and drive it through the speakers. As the name suggests, a preamp is the first element in the chain of this operation.
Some Examples Of The Differences
Let’s say you’re a guitarist and you have an electric guitar. To achieve that “electric” guitar sound, you need to plug your instrument into an amplifier.
With each stroke of the pick, you create string vibrations that emit a frequency or note which is then captured by the pickups. The pickups convert this into an electrical signal, which travels through a simple guitar cable that is plugged directly into the preamp of the amplifier.
A preamp, much like an amplifier, boosts weak signals. In this case, the preamp boosts the signal coming from the guitar and sends it to the amp. The amp then takes that optimized signal and drives the speakers.
To get sound out of your guitar amp speakers, you need an amp – and to connect the guitar to the amp, you need a preamp. The preamp boosts the signal to line level so that the amp can boost its amplitude enough to play through the speakers.
When comparing a preamp and an amplifier, it’s important to keep in mind that one can live without the other. However, in the case of a guitar amp, preamps and amps usually co-exist on the same devices.
Do You Even Need A Preamp?
In modern home studios (and even in large-scale studios), it’s essential to have preamps to connect one or more instruments to record their sound.
To playback your recordings, you need a set of speakers or studio monitors. These need to be powered by an amplifier. The preamps, in this case, work as your input for your instruments. The amp is responsible for the output of the speakers.
Passive Speakers Need A Preamp
Most studio speakers nowadays are “active” speakers, so you don’t need to worry about buying a separate amp to drive them.
Active speakers are self-amplified and don’t need an external amplifier to work, whereas passive speakers need external amplification.
The rules of “active” and “passive” apply to all speakers and monitors. A perfect example of this is when you’re using speakers with mixers. To find out more about active and passive speakers, click here.
The Role Of Mixers
All mixers have preamps that are used to connect our instruments, although not all mixers have amplifiers. “Powered” mixers have amps built-in. These mixers can drive passive speakers that don’t carry a built-in amp. However, “passive” mixers don’t have built-in amps. You need active speakers in order to play sound out of passive mixers.
Amp vs Preamp: Conclusion
There are a multitude of preamps and amps to choose from on the market today, but their core functions are the same. It totally depends on the application to decide which one to use. They are two very different things.