What Is A Reflection Free Zone?
If you do some research on acoustics, chances are you will come across the term Reflection Free Zone or RFZ. In this article we will earn what it is and how to implement one in your own home recording studio.
1) What is an RFZ?
The reflection free zone is an area in your room where you reduce all the first reflection off your side walls and ceiling, so that you get as clear of a listening field as possible. This concept really only applies to control rooms or home studios where you record and listen back in the same room.
You can see in the image below from my own home studio that I have created an RFZ by hanging panels on both side walls and hanging an acoustic cloud directly above my head and slightly in front of me to absorb reflections off the ceiling.
2) How do you set up a reflection free zone?
Once you have dialed in your listening position and your speaker placement then you are ready to treat the side walls and ceiling. To do this you will need a mirror and a friend to hold the mirror as you sit in your listening position.
Because sound and light will both reflect off surfaces based on their angle of incidence, you can use a mirror to see where the sound waves will reflect on your side walls. Here is the process for finding where to hang your acoustic panels.
1) Sit in your listening position facing your speakers.
2) Have your friend hold the mirror directly against the wall in the front right corner.
3) Now have your friend move the mirror slowly along the wall towards the back wall.
4) Look at the mirror and wait until you see the front of your right speaker show up in the mirror.
5) At that location have your friend mark a pencil line on the wall at the left edge of the mirror. This is where you will hang your first acoustic panel.
6) Now have your friend continue moving the mirror along the wall until you no longer see the front of the right speaker in the mirror.
7) Mark the right edge of the mirror on the wall with a pencil. This will be the end of your acoustic treatment.
Repeat this same process for the left wall.
3) Hang Your Acoustic Treatment
Now you will have a space on both side walls between your two pencil lines that will need to be filled with acoustic panels.
I like to build my own panels. If you want to build panels, here is a great tutorial on how to make high quality affordable panels: https://www.youtube.com/watch?v=bWqoRYnYlqE
Once you have bought or built your panels then you want to hang them so that the middle of the panel falls at your ears height when you are sitting at the listening position.
4) Hanging Your Acoustic Cloud
Lastly, we want to reduce the reflections from the ceiling. To do this we need to hang several acoustic panels over our head. The lower you hang the panel the more low end attenuation you will get. You will have to decide how low you want to hang your panel for aesthetics and ease of use in the studio.
Make sure to hang your panel from your ceiling studs to hold up the weight.
That is the theory and application of a reflection free zone. if done properly, it can greatly improve the clarity of your stereo field.
If you are looking to acoustically treat your own home studio then download my FREE Acoustic Treatment Guide to get a full overview of how to treat your own studio.