Setting up a 2.0 subwoofer system for speaker measurements
You can easily measure a speaker setup with an additional subwoofer unit. Simply route your L-R channels through the sub in a 2.0 stereo setup (daisy-chain). To do this, there will be input and output slots available at the back of the sub.
In other words, the subwoofer can NOT be routed on a third channel separately (Reference 4 software only supports 2.0 stereo setups):
How it works
We are using the sub's built-in crossover, which will take care of the low frequency separation between the sub and the speakers. The speaker calibration profile will then work for the entire setup at any given volume. There will be no need to make any separate volume adjustments on the sub after completing the measurements.
In fact, if you make my adjustments on the sub separately after completing the measurements, you might need to recalibrate as the correction balance between the speakers and the sub has changed.
Tips and tricks
Setting up a subwoofer for the perfect measurement can be a little tricky, especially with all the physical settings options on the back of your subwoofer unit. Set the subwoofer level to your liking, perform the measurements and follow these tips:
- Don't change the speaker/subwoofer level and placement relations after calibrating
- If the low frequency correction is exceeding 6 dB, go back and turn down the subwoofer a little, then measure again
- If you can't get a good reading and the applied correction seems extreme, you might have a problem with a room mode: try a slightly different placement for the sub and measure again
- If the measurement suggests that there is still a problem/room mode present, try adjusting the available settings at the back of the sub (Crossover, Phase Inversion, LPF, etc.)
- Use the Limit Controls and Bass Boost/Tilt controls in Reference to fine-tune the correction:
IMPORTANT! If you are concerned about Reference cutting out too much bass, you can always adjust the correction using the Limit Controls and Bass Boost/Tilt controls in the software!
However, it is most likely that the calibration profile is accurate, and your ears simply need some time to adjust to the change. If you still have doubts, simply test by working with the new calibration profile and see how your mixes translate - if the bass response is translating well on other playback systems, everything is working as intended and the calibration profile is accurate!