Does the first reflection point actually matter??

I gave GIK and Acoustical Surfaces a dozen pics of my room for recommendations and they each came up with completely contradictory suggestions. GiK was all about absorbers covering as much of the surface area of the walls and ceilings as possible while AS took a more balanced approach but wanted me to use diffusers for first reflection point and in corners which I thought was odd.

All I got was more confused so im going to buy software to analyze my room first so I dont waste money and make mistakes. Deadening the room can just as easily kill dynamics.

As an aside, i did almost a dozen speaker demos the past month and all dealers had diffusion on the walls between the speakers. GIK said you want absorption between so again conflicting messages.

@aj523

To my experience, as others here have noted, diffusion at the 1st reflection points are a better idea.  They enhance imaging.

Best,

E

Does the first reflection point really matter?

For my 2 cents, how sound reproduction interacts with the room is a Very complex subject.

The original problem for the writers back in the day? Sure, they could all see how important it was, but it all covers so much territory. How do you write about such a varied topic every time out without oversimplifying it to the point of shortchanging it? You don't...because you can't. So, the next best thing is to try to simplify it for 'average' or 'typical' situ's. So everyone ended up with their own 'rules' designed to help keep advice simple...only for every rule there are invariably (too) many exceptions.

Think of it as your 'system' vs the 'room'. Every system has its own ability (or not so much) to project into the room. The total ability of which is made up of the sum of each individual component, wiring, power treatments, EQ, etc. Not only is each system's range and envelope of sound unique, but change just one setting or component and that projection into the room changes accordingly. And for every change in sound projection behavior, there is potentially a different room treatment solution, even if it is only based on using the same room treatment components, just rearranged differently in the room in relation to the stereo...or in relation to the lp. Even that doesn't begin to cover it all.

But, in the case of the first reflection point (or perhaps any other), real-world end results are so often all over the map, from crucially important to nearly non-existent. Because there simply Are no formulas for it that can take all the variations of the system into account, even with a microphone. In the end, I'm tempted to say that the best fine tuning is always going to come from first-hand, empirical experimentation, regardless of how many rules, good or otherwise, may be available, or that can be relied upon to get us 'in the ballpark' first.

In my experience all first reflection points matter, side walls, floor, ceiling, front and back wall, 12 points in all from my calculation. A 40% / 60% ratio absorption / diffusion works well for me. I followed GIK's advice and started with absorption at the 4 side wall points (considered rightly or not the absolute first reflection points by most). To me, in my room, the floor between the speakers and I is the true first reflection point. They all matter IMO.

Well said, @ivan_nosnibor.
Erik,

“The most important part is getting to critical mass in absorption, and adding diffusion in the right areas. - Agreed.

“The laser-line, first reflection points, in my mind, have never born fruit”
Not entirely true. Think of laser line as your reference point. Once you mount the panels using the reference point (first reflection) and moving or rotating them say 15 degrees from the listener’s line of site, so they are no longer exactly on the mirror may result in slight shift in the imaging, IMHO.

Now if you want to cover the entire wall with absorbers / diffusers then taking a systematic approach of targeting a first reflection point is pretty much a mute point :-)