Audio interface (also called digital audio interface device) is equipment that transmits audio information between input and output devices, such as music keyboards or sound modules. The quality of the transmitted audio depends on the physical configuration, power supply and capacitance of the audio interface. It is necessary to use high quality devices to ensure optimum audio quality. What do we mean by quality?
In order to answer this question, we need to understand the differences between input and output. An interface only provides connection between devices. There is no inherent quality in the data itself, only the devices can output that data in any manner they choose. In other words, the quality of the signal is not inherent in the signal itself, rather it depends on the devices and their configuration.
In fact, in some cases, using an interface will cause the recording quality of the source to become sub-par due to factors unrelated to the interface. For instance, if the interface is designed to convert AC signal to a high frequency signal and the recording device uses a high F impedance device, then the quality of the resulting audio may be lower than a similar recording made without the addition of the interface. This phenomenon is called ‘bouncing’ and can be observed when a high F impedance device is connected to an interface with low bandwidth.
However, the quality of the recording device also has a lot to do with it. A good device will have low levels of noise and distortion, high level of resolution and speed, low input impedance and high output impedance. This is because all these properties are required in order to make good recordings. In fact, even a very cheap interface can produce recordings of excellent quality. Therefore, no one can claim that the quality of the recorded material will be negatively affected by using an interface.
Another factor that may impact on the quality of the recorded material is the physical configuration of the microphone or studio. Different setups will use different levels of input and output devices and therefore the sound characteristics of each will differ from each other. However, despite this, most professional audio interfaces consist of certain common elements. For instance, most modern consumer-grade audio interfaces are USB controlled, powered by their own power supply and include a convenient user interface with which to control the volume, panning and input/output levels.
The fact is that a microphone interface will not affect the quality of your recordings at all. What it does affect is the way in which the sound is transmitted from the source to the monitor. If your source device (the recording device) has a very high F impedance then your sound may be electronically distorted.
Also, an audio interface can only help you if the recording device you are using also has an audio interface built in. In other words, if both your microphone and your recording device have a built in interface then you will have a better chance of getting the quality that you want out of your recording.
