COOLCAT said:
I have an old Mix magazine,1997 by Bob Hodas.. with a Woof or not to Woof article.
It says symetrically in the center goes the sub if you only have one.
It also mentions the old wives tale that bass is omnidirectional, and said the old laquer masters for vinyl combined 200hz and below to mono for phase problems..out phase made the cutting lathe jump..but now we can have stereo bass.
The exercise to prove this was to put the sub off to one side of your room and see if you could hear it, proving its not omindirectional.
strongly recommended using a good analyzer too to set up the sub-woofer.
suggestion to lift the sub off the ground too was mentioned.
I have a cheap RTA setup and you can sure see the bass. The volume on my sub was near zero volume too, post setup...but it showed on the graph.
A 1/3 Octave Real Time Analyzer is useless for deterimining flat response from a subwoofer (1/12 Octave is minimum spacing between EQ/Analysis bands to find dips in frequency response caused by room modes - Bob Hodas uses a 1/24 Octave analyzer/EQ).
Subwoofer placement 1/2 (or 1/4 or other even divisions) wall is wrong - this will nearly guarantee some kind of cancellation of an important fundamental frequency. Experimentation is the key to proper subwoofer placement, and most likely 1/3 across a wall, or in a corner is the result. My first two rules of subwoofer placement are: if you choose in advance where the subwoofer will go, it will be wrong - and wherever the subwoofer measures best will end up in a doorway, walkway, or somewhere the wife doesn't approve!
Bass does radiate omnidirectionally, and in a small room (under 12,000 cf) fundamental tones below 100 Hz are not localizable. Subwoofers play harmonic content as well as fundamental tones, so subwoofers may or may not be localizable even if their fundamental tones might not be. Ported subwoofers are almost always localizable. In many cases, a localizable subwoofer delivering flat bass response is preferable to a non-localizable subwoofer playing bad frequency response due to improper placement.
Carpet, spikes, platforms, feet...none of these, or raising a subwoofer a few inches off the floor, have an effect on the FR of the subwoofer unless it is engaging different room modes by the location change.
1. Place the sub after analysis and listening for flattest frequency response
2. calibrate your system according to the Blue Sky instructions, using their test tones
3. Make sure the subwoofer is in-phase with your mains
4. Listen and enjoy!
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