The speakers now have 135 hours on them and it was time for another test. I have been in love with the way the look and sound from day 1. But something has been bugging me with the graphs from bass sweeps earlier in the thread. They did not represent what I heard and I became unsure of what I am hearing (or believe I hear). Some nights ago it became clear to me that it was probably due to a misstake on my behalf. As I am used to calibrate my subs from time to time, I hook up the Velodyne mic through my receiver, a Pioneer LX76.
Time for a new metering session were I connect the signal directly to my amp (Audio Research DSI 200).
Now we are talking. If you compare this graph with the one shown earlier in the thread one can clearly see what a difference it makes. Previously I ran it through the receiver and pre-out to the amp which was set to Processor and acting as a power amp (no pre amp).
Look at the low freq here. This is what I was hearing but not seeing in the graphs. Phew.
I tested different distances from the front wall but amazingly enough I had managed to hit the ideal spot by ear. 88 cm from the wall was the best spot. So instead I tried different listening positions. I have a 3 meter wide sofa and there are limitations as to how far I can move it. But this is what it looks like 8 inches forward from the "ideal position". Here I loose some of the nice low bass.
And this is what it looks like if I move it 20 inches back from the "ideal position". A clear raise around 150 Hz.
When in my sweet spot I sit 150 cm from the rear wall and I have a tailor made book shelf that acts as a diffuser. I have no idea how well this works but I would like to think it its better than a flat wall, as the shelf is full of rounded objects.
I am happy with the sound (and graphs) but I am open to input on how to improve. F ex is the dip around 100 Hz something to be concerned about?