subwoofers and panels don't mix

Mr Tennis - from your post 2 above - can you give me a specific track to listen to and what exactly should one listen for to identify that the woofer and panels don't blend seamlessly? I know when they sound really bad together - but when a system is pretty tuned (and has verifiable flat response at the couch from 20 to 200 Hz) - what exactly do you listen for?

The one thing I am aware of is some localization of the bass - which is obviously undesirable - I'm still trying to dial that in. I have a 20 ft cord and need a 25 to move it an inch from where it is, so I can't play with it too much right now.

the issue is not localization of bass but rather the timbre.

i would suggest that you listen to dave grusin, "keep your eye on the shadow", on sheffield. i have a cd called PRIME CUTS, and it is track 8.

panel bass and cone bass sounds different, just midrange reproduced by a cone and a planar driver also sounds different.

Lightminer,

I would suggest that Shefield Drum track will highlight most of the reasons panels and subwoofers don't mix. Drums are some of the hardest sounds to reproduce convincingly, although other percussion instruments (like the piano) will work well too...Dave Grusin is a good choice.

My guess is you need a critically damped subwoofer which generally means a very large motor magnet structure within a sealed box and not the usual boomy kind (known for total movie noise capability). This means the woofer goes directly to the rest position when the signal drops to zero without any overshoot or additional resonant oscillations. Remember the panel will have good transient capabilities in the sense that it has very little stored energy...

Maybe its because my panels go so low by themselves, but I can't hear a thing that you guys are talking about!! I have the 3.6s. One thing I've learned since then is that my sub is *theoretically* not optimized for use with panels, the Hsu HO w/turbo has more venting length which slows down the sound. The current Hsu, which you can buy a couple of, should match even closer. But I honestly can't hear a thing you guys are talking about. Everything sounds awesome.

Oh - on the Rel only w/Maggies - some also use Martin Logan Depth as that is designed to be fast. But consider the new Hsu, which is not ported (and therefore not slow) at all. The ULS Quad Drive - crazy fast compared to my extra-ported VTF3HOw/Turbo. i have to think that would match really well.

Is there a physics term we can compare that tells us the 'slowness' of the sound?

Another track - with crazy dynamics and bass - The Serpents Egg, Track 9 (Dead Can Dance). You can't imagine it until you hear it.

I welcome anyone in the bay area to send a note through Audiogon and come over and try and show me what we are talking about and perhaps I can hear your system.

Ah, the term is "Group Delay". I am trying to find Group Delay numbers for some of the subs. It would be great if we could get:

Electrostatic panel itself Group Delay at say 300 Hz as refernce.

Group Delay from Sanders Systems integrated sub
Group Delay from Summit X Martin Logan integrated sub
Group Delay from Martin Logan Depth Sub
Group Delay from Hsu Quad Drive ULS-15
Group Delay from Stentor III REL
Group Delay from Stentor Studio III REL

Oh - and these things should be flat to 20, if I find out they roll off at 24, 22 or even 21 then I'm crossing them off, what is the point of all of spending that much money? Mine is pretty flat to 16.

Oh - and we have to put some sort of price limit on it, wasn't there a Krell Sub that used 30 amps circuits or something?

There is a guy 'CraigSub' on other forums and he is sub-crazy (in a good way!). Maybe I can get him to figure this out :).