Originally Posted by Flatliner
I don't know a lot about ported subs so I'm just curious, what was the reason for moving the port from the front to the back? Seems like it would mean placement/ distance from the wall would have more influence with maybe a tradeoff between deeper bass/ more output closer to the wall behind it but more accuracy further away - but that seems to be counter to your suggestion? I have a pair of Vandersteen 1b's for my fronts which are extremely sensitive to distance out from the wall so I'm just trying to get an idea of where to start with sub placement for best accuracy (I don't really listen at very loud levels these days). I'm guessing between the two mains and not really in the corner on the outside of the main pair.
The main reason that you hear very different results with the distance to wall of your Vandersteen is the front speaker has a baffle width related roll off below 200-300hz. Some call this baffle loss which takes place because sound at higher frequency is no longer omni-directional. All speaker designers who know what they are doing will compensate that by boosting the frequency band below 300hz (using voice coil inductance) if they are supposed to be placed off wall. On the other hand, if the speakers are meant to be placed close to wall, the baflle loss will be much less and there shouldn't be much boost below 200-300hz. In short, to get the speakers sound right, you need to learn from the speaker company if they are supposed to be placed close to wall or off wall. Of wall placed front speakers have better image. The reason we have stereo image and sound stage is because wall reflection. The sound played in anechoic room (even if they are in stereo) is very boring. It has nothing resembling what we hear every day. BTW, a lot of members have favored low indutance drivers and forgot about the baffle loss compensation. The resulting sound from a lof of DIY project using low inductance drivers is the mid bass is just lacking, period. This is off topic.
Now sub is different. There is no baffle loss. So place in the corner is ok. The boost from corner loading is supposed to be very uniform. Don't worry about the boomy sound coming from our subs. The reason we hear boomy sound is because some subs do have a very narrow sweet-spot. If you turn the volume low, you don't hear bass, and if you turn the volume up, you hear boomy sound. But our subs address those problems. Once you hear the sound from our subs, you will agree.