How to Calibrate Your Home Theater System: A Step-by-Step Guide

Are you tired of having a home theater system that just doesn't seem to be producing the best sound quality possible? If so, then it's time to learn how to calibrate your system using a Blu-ray demo disc. In this article, we'll walk you through the process of calibrating your speakers and subwoofer using an SPL meter and a Blu-ray demo disc.

First things first, you'll need to set up your AVR (audio/video receiver) to use its internal test tones. This will allow you to adjust the SPL (sound pressure level) of each speaker to 75dB. Once you've done this, verify the SPLs with a Spears & Munsil rev2 disc. To do this, hold your SPL meter pointing at the ceiling at ear level at the Main Listening Position. Set the meter to C weighting and SLOW response.

One important thing to keep in mind is that using an analogue gauge SPL meter can be tricky. This is because these meters are prone to error and may not provide accurate readings. For this reason, it's recommended that you use a digital SPL meter whenever possible.

Now, let's talk about the importance of using the correct reference level when calibrating your home theater system. Some people prefer to use peak reference levels, while others prefer to use RMS (root mean square) reference levels. The truth is that both methods have their advantages and disadvantages.

Peak reference levels are better suited for electrical measurements, such as measuring the output of a signal generator or an audio processor. On the other hand, RMS reference levels are better suited for acoustic measurements, such as measuring the sound pressure level in a room.

In the world of home theater, it's generally recommended to use the RMS scale when calibrating your system. This is because the film industry uses the RMS scale to define reference SPL levels. For example, 85 dB is defined as the reference SPL for -20 dBFS signals.

Programs like Audacity and Adobe Audition allow you to select which reference level you prefer. You can choose between peak value and RMS value for a sine wave. On top of this, there are two references for 0 dBFS: peak value and RMS value.

One interesting caveat when using an SPL meter is that the peaks of a -20 dBFS sine wave will be at -20 dBFS, while the peaks of a -20 dBFS pink noise signal will be at approximately -10 dBFS. This is because pink noise has a 12 dB crest factor, which means that its peaks are 12 dB above its average level.

In conclusion, calibrating your home theater system using a Blu-ray demo disc and an SPL meter is a straightforward process. By following these steps, you can ensure that your speakers and subwoofer are producing the best sound quality possible. Remember to use the RMS scale when calibrating your system, as this is the reference level used by the film industry.

Blu ray demo disc