Dunlavy SC-IVa Set up help

Danlib1: Please enlighten us.

I know a lot of audiophiles who liked the sound of Dunlavy speakers but hated the fact they were so big. And that's why they wouldn't buy them. And some people thought they looked too plain and wanted something "fancier" for their money.

I also know that there were other reasons for Dunlavy's demise, like maybe Dunlavy wasn't the easiest guy in the world for dealers to work with. And some people thought he should use more expensive and exotic drivers. Regardless, I'm not contending that placement isn't vitally important. I'm just questioning some of Sean's recommendations.

The Dunlavy's take into account room response and driver radiation characteristics. Given that Dunlavy placed the woofer at the bottom, which is loaded by the floor, and other woofer at the top, which doesn't have any loading, the output of the woofers isn't symmetrical even though the cabinet is configured that way. This causes one woofer to produce a lot less output at the bottom end than the other. This problem is compounded when there is a greater distance between the top woofer and the ceiling. Since many rooms have varying ceiling heights, bass response from room to room can vary pretty drastically.

By introducing a "sounding board" into the equation and controlling the amount of loading that the top woofer sees by manipulating the size, shape and placement of the sounding board, one can gain much more consistent low frequency output. This is true regardless of the room size and / or floor to ceiling height. This still won't fix a problem with side wall reflections, which an MTM type array is prone towards.

I'm NOT saying that these speakers won't work in a smaller room on a short wall, what i'm saying is that they are best suited to a larger room on a longer wall. So long as you can get them spaced far enough apart AND far enough off of the side walls, it doesn't matter if they are placed on the shorter of the two walls. Calling the Dunlavy's "long wall speakers" simply means that they need room to breath, both between them and on the outsides. If one has a very large room, the short wall might actually be plenty wide enough to achieve optimum performance. Then again, what is "good enough" for some really isn't "optimum" in terms of producing what the speakers really are capable of. Sean
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With limited space, a couple of feet can make all the difference in the world with these speakers. Against my 13 ft wall, to get the 4a's seperated enough, they were almost touching the sidewalls. Having another another foot or two would have helped. With only 12 feet, Im afraid you are really pushing the envelope. Just get those sidewalls treated with some thick sound absorbant material and I would get the room corners taken care of as well. I hung up some plants in the corners and that did the trick. Can you other guys describe this baffle you're talking about? Does it extend out past the front of the speaker or does it just go from the front and straight up?

Cm..I think that you and I may have written before about the baffle atop the speaker..My baffle was adjustable for rake angle and extended from the top of the speaker to almost the ceiling.The baffle started at the top front edge of the speaker and extended up and back to the ceiling at 10 degrees.. Tom

I’m sorry to break this, but you will never get the potential of your IVa’s on the short wall! I have spent many years with my own IVa” and helping others here at Audiogon, and it’s just not possible with your room, to make then work well.
I can save you countless hours by telling you to move on to a different speaker, or set up on the long wall and reconfigure your home theater. Home theater should not dictate your speaker placement if you want the potential from the speakers. The speakers must come first.
Sorry, I’m not trying to be flippant here, I just know this as fact. If you care to take my advice I would follow the subsequent guideline. Your room is 12’x21’ due to the limited width; you’ll be forced to set the speakers 1/5th into the room, or in other words 2’-5” from the wall to the center of the tweeter. The side wall should be at least 1/3rd greater than 2’-5”, in other words no closer than 3’-3” from the center of the tweeter to the side wall. This would give you 14”-6” between tweeters. (You could reduce this amount by up to 1’-0”) Now if your seating position is 1/3rd of the dimension into the room, your ear should be 4’-0” from the back wall. This will put your ear approximately 9’-6” from the tweeter. Next you’ll want to look at toe in: for my speakers in a similar room, I can just see the inside face of the speaker, in other words someone looking down the plane of the inside face of the speaker is looking just behind my ear. If you follow this guideline you will be extremely close to magic, from this spot adjustments should be made in increments of 1/8” a time. It will not take long before the image snaps into place and given the above formula all the frequencies should be time cohesive and present in full spectrum.
If you simply can not do the long wall, sell the speakers, they simply were not designed to be placed the way you have them.
J.D.