Audio Interfaces/Sound Cards

When it comes to modern recording studios, audio interfaces are the nerve center of the operation. A sound interface is a device that allows you to transfer audio between your computer and the outside world, whether you're working in a small home studio or a large media production facility. It is the single most important piece of hardware for many artists and engineers, as it incorporates microphone preamplifiers, direct instrument inputs (with or without metering), headphone distribution (with or without DSP), and even digital signal processing (DSP) all in a single unit. Audio interfaces with a lot of channels take over the job of traditional recording consoles, which are no longer needed.

What are the different types of audio interfaces?

MIDI Interfaces: For even greater flexibility in your recording setup, you can send and receive MIDI signals between your computer and other devices such as keyboards, control surfaces, dedicated audio interfaces, and more. Their 5-pin MIDI jacks allow them to connect to any computer or MIDI-enabled hardware with ease.

Thunderbolt and PCI Audio Interfaces: According to the manufacturer, Thunderbolt audio interfaces provide connectivity speeds that are twice as fast as USB 3.0 and more than 12 times as fast as FireWire 800. However, while Thunderbolt ports are ubiquitous on modern Mac computers, they are uncommon on Windows PCs, and many popular Thunderbolt audio interfaces do not support the Windows operating system. PCIe audio interfaces have specifications that are comparable to those of Thunderbolt audio interfaces, but they require PCIe slots to be installed. PCIe systems are typically designed for high-volume professional audio production environments.

USB Audio Interfaces: In contrast to the older USB 1.1 audio interfaces that you may come across, USB 2.0 is the most common connection type on the market, providing moderate speed and near-universal compatibility with both Macs and Windows PCs. There are many different types of monitoring options available on USB audio interfaces that are "latency-free," ranging from simple analog routing options that allow you to monitor the live input to more advanced onboard digital mixers that may include DSP effects and processing. It is over ten times faster than USB 2.0, and it allows for higher track counts with less latency than the previous generation.

Ethernet Audio Interfaces: These interfaces, which are referred to by a variety of names, including networked audio and audio over Ethernet, are nearly latency-free and have virtually limitless expandability, making them well-suited for complex recording or live sound setups. A lot of people will benefit from this technology if they have multi-room systems that use Ethernet as their main audio interface. 

FireWire Audio Interfaces: Two types of FireWire are found on audio interfaces: the older FireWire 400, which has the same speed as USB 2.0, and the newer FireWire 800, which has nearly twice the speed of USB 2.0 and is nearly twice as fast. Over the course of several years, FireWire became the de facto industry standard for high-speed audio interfaces, and it was almost exclusively found on Mac computers. Most modern computers connect to FireWire audio interfaces via FireWire-to-Thunderbolt adapters, which are available for purchase separately. For the majority of project studio needs, FireWire is good enough. FireWire audio interfaces are also very cheap and have a lot of channels, so they're a good choice. 

What factors should I take into consideration when selecting an audio interface?

Form Factor

Audio interfaces are available in a range of shapes and sizes, although they are typically designed for either desktop or rackmount applications. Desktop audio interfaces are often smaller in size and have fewer connections, but they provide simple access to all of the hardware controls you might require. Some desktop audio interfaces are powered by a bus, which makes them particularly suitable for mobile applications. Most of the time, rackmount audio interfaces can be permanently installed in 19-inch equipment racks, giving them more I/O at the cost of some hands-on control.

Analog and Digital Connections

When it comes to analog connections on audio interfaces, they can be found in a variety of shapes and sizes, including XLRs, 1/4-inch, and RCA connectors, or they can be found in the smaller DB-25 connectors, which can accommodate a large number of input and output channels while taking up little physical space. Onboard microphone preamplifiers can reduce or eliminate the need for external recording hardware to a significant degree. The number of analog connections in an audio interface may be greater than the number of digital conversion channels, so make sure you have enough channels available to meet your recording and monitoring requirements. Similar to analog I/O, digital I/O like an 8-channel ADAT light pipe may make it possible to expand your audio interface without having to buy extra preamps. Some audio interfaces even have MIDI I/O so you can connect keyboards and controllers to them.

Connection Type and Latency are two important considerations.

Latency is a factor to consider if you plan to record with plug-in effects and processors or if you have a large number of tracks to record. Latency is largely determined by the type of connection between the audio interface and the computer. It is generally agreed that faster connections make your audio interface work better.

In-built DSP (Digital Signal Processing)

Onboard digital signal processing and DSP-based mixers are standard features on many audio interfaces, and they can be used to add effects, dynamics, equalization, and monitor mixing to your recordings. This enables you to add reverb or delay to vocals for monitoring purposes, as well as record with EQ and compression, all without increasing the latency of your system in the process. Depending on the system, the onboard DSP might be either fixed or extendable in nature. The DSP in some systems lets them run their own special plug-ins without using up more of your computer's CPU.