ARC - Help my devise a test.......

[dankelly]

I assume the early refections are from the desk. If you mean the one around 0.7 ms, that equates to around 0.24m further travel than the direct sound. Only the desk reflections are close enough to be the cause.

The frequency plots for the measurements left and right of the LP show the 400Hz null move location. Any ideas how to track the source of this?

It would be interesting to get REW to generate Eq's and to compare these to the ARC ones. Is that possible?

Are you asking me to do this? I'll do anything mate, just tell me how to do it.

I've been really surprised myself by the results. I'm surprised none of the EQ haters have anything to say on the matter, maybe that says it all though huh?

[Dange]

Originally Posted by DanDan

Sure thing Dange. I thought the screenshot had them

It has something that's very small along the bottom and it just relates to time and date of measurement. Would be good to know if it's ARC in ARC out, relative position etc.

[dankelly]

Here ya go mate

[DanDan]

dan how do you get the explanatory text on the actual graph? Also you info a the bottom looks clearer than mine, some preference which I can't find?
I am using screenshots as I can find an export/print or whatever in the Overlays screen, is there a better way?
As may be obvious, I am not that familiar with REW as I only recently got it going properly on Mac. It is very extensive and requires some driving lessons..

So, I made a graph as follows:-
Left Speaker Only.
Curves for, Listening Position with ARC on and off, 300mm Left and Right, ARC on.

The purpose here is to illustrate what ARC did and couldn't do.
The 150 area correction seems to hold well over a 600mm width.
So we can sway side to side happily while mixing.....
The 400 area doesn't fare well. The correction, if any, collapses immediately with movement. Furthermore the frequency changes.
The hallmarks of a reflection. I will leave this one to someone with geometric chops, but I am thinking a reflection from the floor will experience a slightly longer path when the mic is moved L or R off centre.
I will post the big question in my next post.


DD

[DanDan]

Here is the Excess Group Delay Graph. I may not have prepared or presented it correctly. I am wondering how to relate it to the 150 and 400 issues?


DD

[JohnPM]

Originally Posted by DanDan

dan how do you get the explanatory text on the actual graph? Also you info a the bottom looks clearer than mine, some preference which I can't find?
I am using screenshots as I can find an export/print or whatever in the Overlays screen, is there a better way?

Use the "Capture" button top left of the graph

[Dange]

For anyone wondering why we're looking at Excess Group Delay. read John's Post here - http://www.gearslutz.com/board/5533725-post3.html Then continue.....

[dankelly]

Originally Posted by JohnPM

Use the "Capture" button top left of the graph

Yeah, if you press the camera icon you get an option to add text to the graph.

You need to write in the text box at the top of each smaller graph on the left, the text that you wish to be in the legend.

[Dange]

Originally Posted by DanDan

Here is the Excess Group Delay Graph. I may not have prepared or presented it correctly. I am wondering how to relate it to the 150 and 400 issues?
Attachment 244643

DD

Is JohnPM available to comment on this? I'm not sure if the plot should dip below zero, looks more like the group delay plot rather than the excess group delay in the post I linked to earlier.......but from what I've gathered the flat regions close to zero are minimum phase therefore should be possible to EQ