Aleph 5 + Dunlavy 4

"Due to the wide horizontal ( but limited vertical ) dispersion of the mirror imaged design that the Dunlavy's use, you'll probably need to pay close attention to the primary points of reflection on the side walls AND toe the speakers in. This type of design typically works best with no toe-in, but your installation somewhat forces you to do so."

I'm not sure if one could call DAL's mirror-imaged, as that implied that some of the drivers are offset, and that is not the case with the speakers. In terms of setup, the DAL's are meant to be toed-into the listening seat rather profoundly. As mentioned, they should be setup on the long wall, and I think the original poster should try that placemat before attempting to implement other corrective measures. Ideally, they should be spread farther apart than the distance from the listening seat to *each* speaker. The setup section in the owner's manual is fairly complete and is best followed for optimal performance.

Best Wishes,
Felix
www.audioannex.com

"What is the theorectical benefit of toe-in ? image and directional treble ?"

Yes, the speakers are extremely directional and have very narrow and well-controlled dispersion characteristics. That's one of the reason why they can be placed fairly close to the room's boundaries without encountering severely adverse effects. Direct toe-in helps the speakers achieve the amazing focus that makes them very special.

I became interested in this thread, because I encountered a similar problem when I first setup my SC-IV's. I placed them in a manner very similar to yours, in a room almost the same size and shape, and had virtually no bass even though I was driving them with a KSA-150. It took me almost a week to open the owner's manual (audiophile pride, you know) and set them up per the manufacturer's instructions. The transformation in the sound was truly spectacular. Since then, I've setup literally dozens of pairs of Dunlavy's, and all of them sounded best with long wall placement.

If there's absolutely no way for you to utilize the long wall, I'd suggest placing your seat directly against the back wall with the speakers moved half-way into the room, as a starting point.

Best Wishes,
Felix
www.audioannex.com

"By mirror imaged, i was referring to the design of each individual speaker as a vertical array, not from side to side. The drivers below the tweeter are a mirror image of the drivers above the tweeter, etc..."

Fair enough, but that's not what mirror-imaged means.

"My experience with toe-in on a speaker of this nature is that it DRASTICALLY limits the size / width of the soundstage while producing a much "hotter" high end and tonally forward presentation. While the center image is increased with toe-in, a certain amount of air / space between instruments is also lost due to increased focusing of the signal into a smaller area. In such a situation, sitting further back ( beyond the distance of creating an equilateral "V" with the speakers ) will produce an increased sensation of the performers being front and center rather than if the speakers were not toe'd in and you were sitting in an equilateral triangle."

AFAIK, you've never setup a pair of SC-IV's. The constraints you describe are somewhat ambitious given the actual performance of the product.

"Obviously, personal preference will dictate what works best for you in your system but the experience of those like Felix who have quite a bit of experience with a product of this type should not be disregarded. Even if we do have different personal preferences : )"

I appreciate that, Sean, but this really isn't an issue of personal preference unless one has a strong desire to live with a distinct lack of bass and focus, basically negating the fundamental design goals of the speakers. There's a very good reason as to why the owner's manual goes into detail illustrating specific placement options.

Best Wishes,
Felix
www.audioannex.com

"Based on the experience mentioned above, I will only add that if one can't place the speakers along the long wall and minimize the amount of "clutter" between the speakers so that they can directly "communicate" from side to side, measurable toe-in will probably be a necessity. MTM speakers are designed to "spray" the sound out horizontally and if the speakers can't "blend in the middle" due to obstructions, one must force the situation by aiming them inwards to the point that the signals are forced to blend together."

The very reason why the drives in the large DAL designs are surrounded in felt is to minimize horizontal dispersion. As such, the speakers are extremely directional and need toe-in to focus the sound toward the listening seat. This is not something that can be debated, Sean, and if you were familiar with the SC-IV's, you'd know this all too well.

I really don't feel right exploring your comments at length (like you know I can), as this forum seems like a happy place and I'm much more comfortable in an unmoderated environment. Suffice it to say that I'm absolutely astonished by the kind of "expertise" I see presented here as actual experience.

Best Wishes,
Felix
www.audioannex.com