Speaker distance measurements: midrange drivers
Measuring speaker distance involves getting up-close to each speaker and pointing the microphone at the midrange driver. This is the first thing you'll be asked to do during Room Evaluation (the second stage of the speaker measurement process).
Which is the midrange driver in my speaker configuration? And why do we need to use the midrange drivers in particular?
The key here is the microphone locating signals, which are set to 1 kHz (1000 Hz). The 1 kHz frequency is normally covered by the midrange drivers, therefore, those are the ones we're using. However, there are so many different types of speaker driver/layout configurations out there, that sometimes it's not obvious which speaker drivers should be used.
IMPORTANT! Most errors during this step are NOT because of the wrong driver used! If you're getting stuck with an error message, or an incorrect distance measured, the error is most likely related to sample rate and stereo field configuration. See solutions for this in the measurement module troubleshooting guide.
Different speaker driver configurations:
- Two-way speakers
- Three-way speakers
- Three-way twin-driver design; vertical/horizontal specifics
- Four-way driver (or more) speaker designs
- Uncommon speaker driver designs
- Different locating signals and reasons for using them
1. Two-way speakers
Plain and simple - this basic configuration only features two drivers. The tweeter is covering the top-end, while the woofer is covering both bass and midrange. Use the woofer, since it covers 1 kHz:
2. Three-way speakers
In a three-way configuration, there is a dedicated midrange driver that covers the 1 kHz frequency, so that is what we're using in this case:
3. Three-way twin-driver design speakers
This is where things get a little more advanced. In this configuration, there is a single tweeter and two equally sized drivers. However, they are actually not equal, despite being the same size. Usually, one driver is covering bass frequencies while the other covers midrange. Find out which is which in the product manual of your particular model. Twin-design models with dedicated midrange drivers are often marked A and B at the back of them. Others, like EVE SC307 in the example below, are compatible both ways and have dedicated switches on them for selecting the woofer driver/midrange driver configuration. In a vertical layout, having the midrange drivers on top is an industry-standard. However, it can be a matter of individual preference too - you might want to work with the midrange drivers on the bottom for your own reasons:
Often times there will be no switches for selecting/flipping the midrange and woofer driver functionality, especially for passive speakers and Hi-Fi speakers. In that case, there is actually a dedicated midrange driver. If it's not obvious which is the midrange driver in this configuration, find out in the speaker product manual. Studio work standard would be placing the speakers with midrange drivers on top:
The same principle applies to vertical twin-driver designs with built-in subwoofers on the sides - the two equally sized drivers on the front are usually covering different frequency ranges. However, in this case, you might want to dive deeper and find out more specifics on the freq. ranges of each driver. You'll still need to use the drivers that are covering the 1 kHz frequency. If this doesn't answer your question, go to point No. 6 below for more advanced ways of completing this step (different locating signals and reasons for using them):
For horizontal layout - in our experience, having the midrange drivers on the inside (closest to each other) is an industry standard. However, it can be a matter of individual preference too - you might want to work with the midrange drivers on the outside for your own reasons. Again, if you're not sure which driver is dedicated to midrange, find out in the product manual and proceed to set up the layout according to your preference. Speakers are often marked A and B at the back of them if there is a dedicated midrange driver. Others, like Focal Twin6 BE in the example below, are compatible both ways and have a left-right switch at the back which flips the driver functionality. Keep in mind that the distance is going to change depending on this layout:
4. Four-way driver (or more) speaker designs
Things are getting simpler again when there is a dedicated midrange driver for the 1 kHz locating frequency. Hot tip: use the midrange driver that is the smallest as long as there is an even smaller additional tweeter:
* This article is incomplete - more content will be added for speaker designs with multiple midrange drivers and other uncommon speaker/driver types. There will also be an additional guide for using B and C locating signals (available in the measurement module settings). Essentially, the additional signal options are there for configurations where there are multiple midrange drivers, so you have more locating signal options to adapt to the specific midrange driver freq. range you want to use (B and C signals are set to different frequencies to the standard 1 kHz of the standard signal). Another reason why you might want to use B or C locating signals is a situation, where the standard 1 kHz signal is too resonant and problematic in the space you're working in. More on that in measurement module app troubleshooting guide.
Please reach out to our support team if you're still getting stuck for any reason!