which 8 to get

Lloyd is an SPL guy, but he is very experienced at it.  I agree that they should have used the same alignment for each driver instead of the same enclosure.  That would have provided a much more accurate test.  But I believe it will give the original poster an idea of what the differences between all the drivers are.    That's why I provided the link.  I wouldn't say it is totally useless.

Steven Kephart

Adire Audio

I think the multiple errors in testing compound to a point approaching uselessness.  I really don't know what good anyone can possibly hope to extract from that page.  The only portion of the page marginally useful, in my opinion, was when they made comments about the physical features, i.e. the tinsel leads are too close together, etc. 

Steve, what can the original poster gain regarding the differences between the drivers when the measured differences are inherently flawed because of the ill-executed testing measures?  You see real testing being done all the time at Adire, I assume.  How does this test compare?

Furthermore, I can just see these guys sitting around doing the 'SQ' test.  The results are probably completely opposite of what people would generally consider good sound quality.  I can just picture it, "dude, Korn hit extra hard on those (high distortion) subs, they have eleeeeet 'attack'."  I wonder if they even tried to level out the SPL level (NOT WATT LEVEL) before doing the 'SQ' test.  Research has shown that our minds prefer higher SPL when comparing two drivers.  Were the tests even blind?  Ranking the drivers by SPL at a given watt level - good job guys, way to rank the drivers by efficiency.  Hell, they didn't even do that since they used different alignments.  What did they even show? 

Am I being unfair?  What _did_ they do right?

To give them some credit, I applaud their efforts to TRY to help the community.  Next time they should take an extra 10 minutes to think things through.

Well the build differences was one thing.  Even though the frequency response graphs aren't too accurate due to differing alignments.  It does give an idea of which driver has better low end extention, or which driver will have a really peaky response.  I think the enclosure chosen was probably a good size for the test as most of them probably are designed for a similar size enclosure.  I wouldn't be surprised if the response is accurate to within a few dB.  the differences in the response graphs between many of the drivers was much larger than that. 

Here's a link to the discussion thread about that test: http://forum.soundillusions.net/showthread.php?t=45741&highlight=great+challenge  Here's an excerpt from Lloyd about the testing:

"I'm not gonna sit here and argue that the boxes chosen were perfect for each driver... however the majority of woofers tested, did have reccomended volumes that we met...

Well not even close.  But then I wouldn't expect it to.  We have VERY expensive software and hardware designed for testing speakers.  But then it is much more important for us to have much tighter resolutions on our testing and be much more accurate.  To be honest, if they did have the equipment we have, I would be much more hessitant about their results.  This is because we find that people who try to use it don't know what they are doing and get inaccurate results or don't know how to read the results.  We had some people freak out on one forum because our Extremis driver had higher distortion than two other drivers at one frequency.  Of course they failed to notice that the distortion for all three drivers was well below 1% which is inaudible.  They also failed to see that we have much lower distortion numbers at levels where distortion does become audible. 

Well if it helps, one of the guys who did the SQ testing was Nick Lemons, owner of Stereo Integrity (a small speaker manufacturer).  Also his dad installs pipe organs for one of the largest organ manufacturers.  He's a pretty good guy and seems to have a good ear.   

It's too bad our driver didn't make it to the SQ portion because I know it would have faired well.  But they greatly exceeded it's power handling on the SPL testing.  It only has a short coil, unlike all those SGLC drivers.

Steven Kephart

Adire Audio