Translate This Pageericwisgikl wrote:Source of the post I put your measurements into Sketchup, traced side walls lines till they meet, measured the angle, which is about 11.5º, and traced a line al 5.75º, the half of them both. Then I took measurements from right side wall to this centre line, and that is your new center.
Amazing, thank you!
endorka wrote:Source of the post Definitely - see the walking mic link test link for a method to do this rigorously.
Lot's of testing today using a slightly simplified walking test method in two different speaker positions.
Test 1 "Symmetrical" test is essentially the same listening position as before but with the left speaker brought forward approx 22cm to bring it in line with the 'symmetrical centre' of the room as described by Eric above. 20cms inside the equilateral triangle is where it sounds best to my ears so this is marked as '0' in the walking test. So '+20' is the tip of the equilateral triangle (I've read Stuarts and John Sayers posts about how equilateral triangles are not necessarily the ultimate, I prefer a wider image personally but my room has some obvious width limitations)
"Symmetrical test" positions:
Baseline test mdat:
Walking test (where '0' is same position as above):
The second round of testing was the 'Corner' test. This is with the speakers pushed right up against the back wall and in the corners.
To get them in there I had to remove the 100mm absorber panels you can see in the photo above.
To keep things in line with the symmetrical method the left speak is again brought forward approx 22cms so it's not quite in the corner.
Again the listening position is 20cms inside the tip of the triangle so is marked as '0' on the walking test.
The corner position seemed to raise the DB level by 1-2 db so I had to re-calibrate REW to compensate for this.
This is a sketch of the test positions:
'Corners' test baseline:
'Corners' walking test (where '0' is the same position as the 'Corners' baseline above):
The bass was definitely different in the Corner tests. In some positions it was smoother for sure. But the big drawback that I immeadiately noticed was the loss of definition in the mids. You can see this on the tests. A big dip in the 2-4k region. This really surprised me and I have no idea why this has happened. I moved the side absorber panels back when I moved the speakers back so I don't think that's it. One thing that I couldn't move is the cloud. In the usual (1st) position the speakers are just under the front end of the cloud, but in the corners they would be approx 40cms in front of it. The cloud is very large and would certainly be blocking first reflections still in this position. No idea how to explain this loss of mids but it really ruins this corner position. I will take smooth mid response over smooth bass any day, but I am determined to try and get both!
One final test which is interesting is another full L / R / L+R measurement from the exact mic position from the "Symmetrical Baseline" test, but with the speakers moved to the corner position. I thought this might illuminate which issues are SBIR and which issue are modal.
There's a lot of data here and I'd love it if anyone had the time to take a look at it. At the moment my initial position still sounds the best to me, I'm guessing because of the flatter mid response.
Thanks all, Civvie.
