# AudioBuffer & AAX

**URL:** <https://forum.juce.com/t/audiobuffer-aax/18264>\
**Category:** Audio Plugins\
**Created:** [June 30, 2016, 10:00pm UTC](https://forum.juce.com/t/audiobuffer-aax/18264 "2016-06-30T22:00:46Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![zabukowski](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/zabukowski/32/507_2.png) [@zabukowski](https://forum.juce.com/u/zabukowski)\
**Post date:** [June 30, 2016, 10:00pm UTC](https://forum.juce.com/t/audiobuffer-aax/18264/1 "2016-06-30T22:00:46Z")

</div>

Inside my plugin’s processBlock function, i need to detect empty buffers (silence).

> float maxVal = buffer.getMagnitude (0, buffer.getNumSamples());

So if maxVal is zero, buffer is empy. This is working perfect with VST format for example.  
Unfortunately, this is not the case with AAX - when buffer is empty, instead of zero i get value 2.1684e-019.

I guess this is because Pro Tools are using fixed-point format? If so, what is the best way in JUCE to convert fixed-point values to floats? Am i missing something?

Thx!

---

<div class="post-metadata">

**Author:** ![frankfilipanits](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/frankfilipanits/32/545_2.png) [@frankfilipanits](https://forum.juce.com/u/frankfilipanits)\
**Post date:** [July 1, 2016, 1:55am UTC](https://forum.juce.com/t/audiobuffer-aax/18264/2 "2016-07-01T01:55:15Z")

</div>

It’s not because of fixed-point; TDM was fixed-point but AAX is floating. Here’s the actual root cause, from the Avid dev forum:

> The “silence” signal which Pro Tools routes to native (i.e. non-HDX) signal chains includes a pulse with value 2^-62 every 32 samples. You can use this level as your silence threshold. Alternatively, you can use -144 dB, which is the canonical threshold considered as silence for Pro Tools features such as Dynamic Plug-In Processing and Track Freeze.

---

<div class="post-metadata">

**Author:** ![zabukowski](https://sea2.discourse-cdn.com/flex026/user_avatar/forum.juce.com/zabukowski/32/507_2.png) [@zabukowski](https://forum.juce.com/u/zabukowski)\
**Post date:** [July 1, 2016, 3:56am UTC](https://forum.juce.com/t/audiobuffer-aax/18264/3 "2016-07-01T03:56:38Z")

</div>

Thank you very much !!!