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jessie.dazzle wrote:

Though the frames have wheels and roll very easily, my room is cursed with an elevated platform smack in the middle of everything (about 14 inches higher than the main floor), and to move the horns up on to or down off of this platform requires taking everything apart. Over 1600lbs of horn and frame; I would not try pushing it up or down a ramp... so, about 5 hours to dissamble, move, and reassemble once off the platform.

Yep, welcome to the club. To move this thing over a room is very troublesome, I usually if I willing to do so take the upperbass horn out of frame. The rest becomes extremely blocky but more manageable… The good/bad part is that you might not need to move anything else besides the upperbass horn… :-)

jessie.dazzle wrote:

My lower mid horn is a 180Hz tractrix, band passed from 800 - 3200Hz, its output is not attenuated. Romy calls this the "Fundamentals Channel"; its contribution is truly fundamental, to the point that if I had to reduce my system down to a single horn system and could keep only one horn, this would be it (maybe I can start a movement!). The horn sits up on top of the stack, which when seated in the near field (less than 10 feet) means that you do notice sound coming from above... I would not say its a problem, but it is not the same as a perception where everything originates from around ear-level.  Anyway, you can probably guess what's coming... With the horns set up on the main level, I decided to put the couch up on the platform, which puts one's ears about in line with the tweeter. Results... Good idea!

OK, Jessie, not you enter the realm of fine tuning of your system. Your solution with platform is elegant but it cures symptoms not the courses. I personally do not feel that you use Fundamentals Channel properly. You desired to run your Fundamentals Channel up to 3200Hz but it is too high. Take a look, you have your MF channel I presumed crossed at 3200Hz with 3uF cap, at least it is what I have. However it is juts electrical crossover point. Do not forget that the secondary resonance of S2 driver pushes a large boost at 1250Hz making the S2 to response flat down to 1000Hz. Your Fundamentals Channel does not die at 1000Hz but run all the way to 3200Hz. The 3200Hz with first order is a nice and opened MF driver with a lot of HF extension in it. The HF extension makes the channel to be too identifiable height-wise. Also, the HF extension from Fundamentals Channel crates some lobbing problem in regards to MF channel. So, what you need to do is to found a right balance between the Fundamentals Channel and MF Channel.

When you said that your Fundamentals Channel is the single horn that you would keep I imidetaly sensed a problems. The in my few the Fundamentals Channel should not push recognizable Sound but rather the unpleasant boom noise. Portend a hypothetic guitar. The sounds of strings shell come from MF channel. The sound of guitar’s deck shall come from Fundamentals Channel. The sound of the room where the guitar plays shell come from the Upperbass Channel.  In your case I feel the Fundamentals Channel work too high.

Do the following – put two channels ONLY in operation: the MF and Fundamentals Channel. Run the RTA with MF channel and found out where the MF will roll off. Set the Fundamentals Channel at the very same point and listen both of the channels, running the low-pass crossover point on the Fundamentals Channel you will soon or later found the one you feel is right. I ma conversed that it will be lower then what you have now. When I did those experiments I detected that adding the 100-200Hz to low-pass crossover point on the Fundamentals Channel is auditable. Anyhow, when you will be lowering the Fundamentals Channel low-pass crossover point you will reduces the Fundamentals Channel’s HF out and it will reduce the ability of the Fundamentals Channel to lift up the imaging of the MF channel. Generally what I feel that implementation of Fundamentals Channel shell not lift up system vertical imaging. If it still does do then you might use a trick: lowering the Fundamentals’ low-pass crossover point but increasing the Fundamentals’ amplitude (I have an attenuator that allows me to fine-tune the Fundamental’s channel output).

jessie.dazzle wrote:

(I once left my door open as he passed by; he stuck his head in and, upon seeing the horns, stuck a finger to his temple, rotated it a quarter turn while looking me in the eye and doing his best to express sincere pity)

Oh, Jessie I was laughing for 5 minutes upon reading it. The sad part that I very much agree with that guy….

jessie.dazzle wrote:

The discovery is how simple it is to recenter the listener. The other nice thing is that when listening while standing (off the platform), one's ear is maintained at the correct altitude.

If you lower the crossover point at your Fundamentals Channel then when a listener will be standing and the Fundamentals Channel will be shooting right into the listener’s ears then you will lose the neutrality of balance.

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