Acrobat is a PDF software from Adobe and is used to create, read and edit PDF documents. Acrobat has useful features that make PDF creation and editing PDF easier and more productive. Commenting on a document is an easy way to let readers know what you think about a document or parts of a document. However, it may be a lot of work to type the comments. It is worth learning how to add audio comments in Acrobat Reader.
How to add Audio Comments in Acrobat Reader
Adding audio comments to Acrobat is available for both the free version (Acrobat DC) and the paid version (Acrobat Pro). Adding audio comments to Acrobat can be done by directly recording the audio in Acrobat or adding a pre-recorded file. Take these steps to add audio comments to PDF in Acrobat Reader.
- Open the PDF
- Select Tools
- Click comment
- Add comment
- Save
1] Open the PDF
The first step is to open the PDF document that you want to add a comment to. The PDF document may also be a PDF document that you are currently working on.
2} Select Tool
Go to the top of the document window and select Tools.
The Tools window will open showing the tools available and those that can be downloaded.
3] Click comment
In the Tools window, click comment.
4] Add comment
When you clicked comment from the previous step, a toolbar was added in the document window. This toolbar is the comment toolbar and it is added to the top of the document window. The comment menu has all the options and tools that have to do with, commenting or adding enhancements to PDF documents.
To add the audio comment to the PDF in Acrobat, look for the paperclip icon on the comment toolbar. The paperclip icon has a plus on it as well. This icon is the Add a new attachment button.
Adding pre-recorded audio comment
Click on the Add a new comment button and a drop-down menu will appear, click Attach file.
The mouse cursor will turn into a pushpin. You can then move to the part of the document where you want to place the audio comment and click.
When you click the space for the comment, the Add attachment window will appear. Choose the file that you want to attach and click Open. 
The File attachment properties window will appear. you will notice that there are tabs in this window. the tabs are Appearance, General, and Review history.
Appearance tab
In the Appearance tab, you can choose the icon that you want to appear in the PDF. The icon choices are Graph, Paperclip, Attachment, and Tag. Whichever icon is chosen, the corresponding symbol will appear at the place where the comment is placed. A graph icon will show if you choose graph, a paperclip icon will show if you choose paperclip, a pushpin icon will show if you choose attachment and a tag icon will show if you choose tag.
You can choose the color of the icon that will show. You can also change the opacity of the icon that will represent the attachment.
General tab
In the General tab, you can change the Author, Subject, and description. The default author is the name of the computer on which the document was created. You can choose to change the author to whatever name you want. The default subject would be File attachment, you can change the subject to make it the subject of the document or the clip. The description box would be blank, here you can describe what the audio or document is about. Modified will show the date that the document was modified, this cannot be changed from the File attachment properties window. The last item is Name, this is the name of the audio clip or file that is attached to the PDF.
Review History tab
In the Review history tab, you will see a list of any changes of status for the comment.
You will notice that at the bottom of the window, you will see two options to check. The options are Locked and Make properties default. You do not have to choose any of the options, you can choose one or you can choose both. Locked will make it so that no one can delete the comment or edit the changes you made in the File attachment properties window. Make properties default will hold the changes you made in the File attachment properties window as the default for other attachments.
When you have finished choosing the options you want, press OK to confirm or Cancel to close the window without keeping the changes.
To make changes to any of the properties of the file attached, right-click on the File Attachment icon and choose Properties. This will open the File attachment properties window.
This method using the Attach file can be used to add files such as videos, images, Word files, PDFs, and much more. It is not only limited to audio comments.
Recording audio comment
Acrobat allows you to record audio comments if you have a built in or external microphone. The steps to recording the comment shares some similarities with adding the pre-recorded comment. The difference is that when you choose Record Audio from the drop-down menu on the Add a new attachment button, you are given the option to record rather than choose a file.
Follow the steps above to place the comment menu bar at the top of the document window then go to the Add new Attachment button and click it. instead of choosing Attach file choose Record audio.
The cursor will change to a speaker icon.
Click on the spot where you want to add the audio attachment. When you click the spot where the comment should appear a Sound recorder window will appear.
To record the audio through the microphone, click the red record button to begin recording. When you are finished recording click the black square to end the recording. You can then play the recording before you click Ok to commit it. if you are satisfied with the audio comment, click Ok to keep it. Otherwise, you can click the red recording button to record another audio comment. 
When you click Ok the Sound attachment properties window will appear. you will notice that there are tabs in this window. the tabs are Appearance, General, and Review history.
Appearance tab
In the Appearance tab, you can choose the icon that you want to appear in the PDF. The icon choices are Ear, Microphone, and Sound. Whichever icon is chosen, the corresponding symbol will appear at the place where the comment is placed. An ear icon will show if you choose the ear icon, a microphone icon will show if you choose the microphone icon, and a speaker icon will show if you choose the sound icon.
You can choose the color of the icon that will show. You can also change the opacity of the icon that will represent the attachment.
General tab
In the General tab, you can change the Author, Subject, and description. The default author is the name of the computer on which the document was created. You can choose to change the author to whatever name you want.
The default subject would be Sound attachment, you can change the subject to make it the subject of the document or the clip.
The default description in the description box would be Sound clip and the size of the sound file in brackets.
Modified will show the date that the document was modified, this cannot be changed from the File attachment properties window.
Review History tab
In the Review history tab, you will see a list of any changes of status for the audio comment.
When you are finished click Ok to add the audio comment. If you want to listen to the comment after it is added, right-click on the icon and choose Play File.
To make changes to any of the properties, right-click on the Audio comment and choose Properties. This will open the Sound attachment properties window.
Adding audio comments by browsing
On the Sound record window, you will notice that there is a Browse button. If you click the browse button it will open the window where you can choose an audio recording to add as the audio comment. If you chose to add the audio comment this way then the audio file types supported are .wav, .wave, .aif, .aiff, and, .aic.
PDF document with multiple comments added.
Click on the comments added to the PDF and you will see the comment and some of the properties on the right of the PDF window.
You will see three dots on the comment on the right side of the window, click the dots to see the menu options. From here, you can select to go to the Properties, Edit, Delete, Set status, Edit or view the properties and add a checkmark to the audio comment.
Read: Type of Smart Objects in Photoshop and how to use them
Can I add multiple comments to a PDF document?
You can add multiple comments to a PDF document. If you add the comments as files this will allow you to add many different file types. You can add many different file types such as audio, image, PDF files, Word files, and many more. If you add the comment as an audio file by using the browse button on the audio recorder then the file types will be limited to .wav, .wave, .aif, .aiff, and, .aic. You can also record the comment and add it to the document.
How can the comments be deleted?
The comments can be easily deleted, just right-click on the comments in the PDF document. The menu will appear, click delete. This will delete the comment from the document. You can also delete the comment by clicking it on the right side of the Acrobat window. You will see three dots on the comment, click the dots to bring up the menu, and from the menu click Delete. The comment will be deleted without asking for confirmation so be sure that you want to delete it.
