Surely you recall last week’s chapter in the spaciousness saga. The story goes on, and TubeTraps are invited to the party!
Remember, we need the late reflections to be 20 dB down and 20 milliseconds delayed. We saw that the air losses from extra distance do not adequately attenuate the sound. How, then, do we simultaneously diffuse and soften the reflections?
Using a combination absorber/diffuser, you say? Correct!
The mechanical properties of a TubeTrap’s one-of-a-kind diffuser provide a slightly “softened” reflection, perfect for spaciousness enhancement.
Now, we continue to learn how to create the room sound we want by answering these questions:
What are some ways to create the needed time delays?
What is the best tool for the job?
Exactly where do I place it and how do I aim it?
Let’s find out how to create a……
Another snippet from the notebook of Art Noxon, PE. The original page is attached.
…SPACIOUS SOUND ROOM
by Art Noxon
There is an area along the back wall, just in from the corner. It is about half way between the speaker and the side wall. The reflection from this area causes a “wall wash.”
TubeTraps are placed along the sidewall so they intercept the wall wash reflection. The treble diffuser panel is rotated so only the wall wash is reflected to listener.
The listener hears the direct signal at 10′, then hears the reflection from the curved cylindrical diffuser (#2 TubeTrap). The path difference is 10 – (16 +6 + 8) = 10 – 30 = -20 feet delayed, or about 20 milliseconds. Recall from last week that we want this reflection to be about 20 dB below the direct signal so that it is a spacious signal.
The diffuser panel is set toward the back wall. In this position, the TubeTrap absorbs the early reflection from the right speaker and crosstalk reflections from the left speaker. This maintains the pinpoint imaging and sound stage.
Early side wall reflections are absorbed and replaced by late sidewall reflections all by the same set of sidewall TubeTraps. This technique creates quiet, very time delayed side wall reflections: the acoustic signature of a wide, spacious room.