See SQL Control Server permission
section in the Getting Started guide.
Please note that the Control Server role is required on the SQL Server that is processing the audit logs, not on the SQL Server that is generating them. For example, let say, you want to audit a SQL Server 2014 instance on server-1. You setup auditing and make the audit files accessible to server-2 (for example a shared folder on server-2). Install LOGbinder on server-2 and also install SQL Server Express 2014 or later on server-2. Now you need to give the LOGbinder service account Server Control role on the SQL Server Express on server-2 only. Once we have the audit files generated by the SQL Server on server-1, we don't need to touch that instance anymore. The processing can take place by another SQL Server installation.