Web SDRs (online receivers) are invaluable tools for judging how you sound compared to others. This works particularly well when in a QSO with several other stations on lower bands such as 80M where one receiver is likely to pick everyone up. Select a receiver at www.websdr.org either from the list or using the world map at the bottom of the page. Next, set it to your frequency and mode, then use the Record feature to grab a sample of you along with others. That file can then be downloaded for playback on your computer. This is probably the most objective method for evaluating your audio and how it compares to others.