---
title: kNumberOfResponseFrequencies
framework: audiotoolbox
role: symbol
role_heading: Global Variable
path: audiotoolbox/knumberofresponsefrequencies
---

# kNumberOfResponseFrequencies

The maximum number of frequency response bin structures for the AudioUnitProperty_FrequencyResponse property.

## Declaration

```swift
var kNumberOfResponseFrequencies: Int { get }
```