Using two microphones to remove room modes from bass measurements

[Keith_W]

How about down to 60-70Hz ?

Probably not, unless your room is the size of a basketball stadium and you are sitting very far away. Calculate the Schroder frequency of your room, that will tell you where your modal zone is. All speakers within the modal zone should be corrected together with the room, preferably using spatial averaging.

 

[3ll3d00d]

All speakers within the modal zone should be corrected together with the room, preferably using spatial averaging.

it's still technically correct to separate speaker design from room correction which means there is potential for some filter designed to lift/tame the low end of a woofer for the same reasons that you would do the same to a sub. However shifting the frequency up an octave or two doesn't change the fact that you should be able to do this via your model.

The other thing to bear in mind is that where you place the speaker/sub in room can have a big impact on it's native response even ignoring the listening position response and that that can be v hard to model e.g. if you position a sub such that it fires into a solid surface in such a way as that the volume it fires into is largely enclosed then you can turn a sealed sub into something that behaves like a bandpass albeit one where one "enclosure" is leaky, modelling that a priori is not generally possible & anechoic is a waste of time so all you have left is in room. Similarly designing a filter for anechoic response when you plan to mount in or on wall would not be too sensible.