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terry j · 30th August 2009

Ok, using my mains (the beautiful diy ones with 18 inch PHLs remember!

) and with measurements done at the lp, think I have finished the preliminary testing.

Trouble is, there will be loads of graphs, hope that is not a problem.

I filled in the void behind the compressed fg facing layer by layer with normal ceiling f/glass. I also did my own test of going to three layers (with the view of going to four if indicated).

So that is what I will show first. Sorry for the number of graphs to come, can't see any other way? (it's confusing to have multiple graphs shown simultaneously)

No layers *purple* (ie completely empty and no facing) with one layer added *blue*

now one layer *blue* and the second layer *red*

Two layers *red* and three layers *purplish*

My conclusion is that the third layer did not bring enough benefits to keep it there, so it will come back out.

Anyway, the three layers were there when I put the facing back up, so this graph is three layers *purplish* and three layers plus facing *ocherish*

Hope that was not too confusing, but shows the progression as I added each bit.

May as well show nothing and everything, three layers and facing

***********************************************************************************************

Purely according to the FR I decided the third layer was not warranted.

then I looked at the decay times for two and three layers

they go down in this graph along the 100 hz line according to two, three and three plus facing. Anyway, even tho the FR change from two to three layers was nothing to get too excited about, I did like the improvement in decay times.

that is one third octave bands.....'but a funny thing happened on the way to the forum'....if I switch to one octave bands, the three plus face suddenly switches and becomes the longest!!

Arrggh, hope I hear in one third octave bands!!

Can someone help me interpret what is going on there?

That is more than enough graphs for one sitting, the main point is that I should have enough to be able to compare what we want when I add the couplers.

Any requests with this, or is it fine for now? (must remember to save the measurement set!!)

30th August 2009	#21
terry j Gear maniac Joined: Jul 2009 Posts: 296 Thread Starter	Ok, using my mains (the beautiful diy ones with 18 inch PHLs remember!) and with measurements done at the lp, think I have finished the preliminary testing. Trouble is, there will be loads of graphs, hope that is not a problem. I filled in the void behind the compressed fg facing layer by layer with normal ceiling f/glass. I also did my own test of going to three layers (with the view of going to four if indicated). So that is what I will show first. Sorry for the number of graphs to come, can't see any other way? (it's confusing to have multiple graphs shown simultaneously) No layers purple (ie completely empty and no facing) with one layer added blue now one layer blue and the second layer red Two layers red and three layers purplish My conclusion is that the third layer did not bring enough benefits to keep it there, so it will come back out. Anyway, the three layers were there when I put the facing back up, so this graph is three layers purplish and three layers plus facing ocherish Hope that was not too confusing, but shows the progression as I added each bit. May as well show nothing and everything, three layers and facing *********************************************************************************************** Purely according to the FR I decided the third layer was not warranted. then I looked at the decay times for two and three layers they go down in this graph along the 100 hz line according to two, three and three plus facing. Anyway, even tho the FR change from two to three layers was nothing to get too excited about, I did like the improvement in decay times. that is one third octave bands.....'but a funny thing happened on the way to the forum'....if I switch to one octave bands, the three plus face suddenly switches and becomes the longest!! Arrggh, hope I hear in one third octave bands!! Can someone help me interpret what is going on there? That is more than enough graphs for one sitting, the main point is that I should have enough to be able to compare what we want when I add the couplers. Any requests with this, or is it fine for now? (must remember to save the measurement set!!)