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# init(componentDescription:options:)

Synchronously initializes a new audio unit object.

```
init(componentDescription: AudioComponentDescription, options: AudioComponentInstantiationOptions = []) throws
```

## Parameters

`componentDescription`

The component to instantiate.

`options`

Options for loading the unit in-process or out-of-process.

## Return Value

An initialized audio unit, or `nil` if initialization failed.

## Discussion

This is the designated initializer.

A single audio unit subclass may implement multiple audio units—for example, an effect that can also function as a generator, or a cluster of related effects.

> Handling Errors in Swift:
> In Swift, this API is imported as an initializer and is marked with the `throws` keyword to indicate that it throws an error in cases of failure.
> 
> You call this method in a `try` expression and handle any errors in the `catch` clauses of a `do` statement, as described in [Error Handling](https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html) in [The Swift Programming Language](https://docs.swift.org/swift-book/) and `About Imported Cocoa Error Parameters`.

---

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