Ah, I hadn't thought of that. I see what you mean.
-
Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
Never Put Subwoofers In Corners... Even with DSP and Multi-Sub Setups?
Ah, I hadn't thought of that. I see what you mean.
This is my current plan because that is where the space is located. When my Rythmik subs come in, I'll measure and see how well it works.
- Rich
Last edited:
I like Wayne's flanking subs concept, wherein he places stereo subs halfway between the main speakers and the wall behind them, to fill in the wall bounce dip. They probably help smooth the in-room response in other ways as well.
Here's a quote pulled from one of the posts you linked to:
"You aren't looking for phase coherence, actually just the opposite. We're looking for phase difference. If the mains were coherent with reflections off the walls, ceiling and floor, we wouldn't need flanking subs. But they're not, and the interference that results creates distinct peaks and dips in various places throughout the room, especially at low and low/mid frequencies in the modal range. So we have to abandon the idea of coherent summation, and go for the next best thing, which is dense interference. It makes the modal range act a little more like the reverberant field, statistically averaged in a sort of homogenous sound distribution throughout the room."
LightninBoy
Addicted to Fun and Learning
"never put a subwoofer in the corner"
Is that you, Patrick Swayze?
Is that you, Patrick Swayze?
No, that is not quite exactly true (Referring to previous answer).
Hearing is pressure-sensitive - SPL. While we can detect direction down to around 60Hz, the harmonics will be what determines perception of sound source location, because the directional cues from the harmonics are so much larger they completely mask the lower frequency direction. To get good localization and realistic images of bass instruments, you need to address early reflections in lower midrange - fix that, and bass instruments will move to their intended location. The bass-system should always be mono, there are reasons for that.
Tactile sensations are more complex than hearing. Sound intensity, particle velocity and phase between velocity and pressure has significance for how the sound is experienced on our body. But direction is not important for tactile perception, and generally we can not detect direction of a soundfield through tactile feel.
If you measure the soundfield in a room at low frequencies, you will find that direction is all over, and does not correlate to location of the speakers. So when you think you hear bass coming from one speaker, it is the higher harmonics you hear, because the direction of the sound in itself is determined mostly by room acoustics.
Hipper
Addicted to Fun and Learning
If I were to play test tones (such as these from Real Traps: https://realtraps.com/test-cd.htm ), which presumably do not have any harmonics, making them come from say the left speaker only, could I test this idea that below around 60Hz we can't detect the source?
Hipper
Addicted to Fun and Learning
Peddle power!
I knew of battery and of course mains power. Presumably you get a partner to do this in another room because of the noise - rusty chains, groans and grunts of your slave.
Hi Kvalsvoll,
Your post is excellent and educational, explaining things to a deeper level of understanding than I could have. Thank you.
I do have a question about one thing:
Could you mention what those reasons are? You don't necessarily have to go into detail. I'm interested in what line(s) of thinking led you to that conclusion.
Thanks.
Your post is excellent and educational, explaining things to a deeper level of understanding than I could have. Thank you.
I do have a question about one thing:
Could you mention what those reasons are? You don't necessarily have to go into detail. I'm interested in what line(s) of thinking led you to that conclusion.
Thanks.
I look forward to his reply, but my 0.02 is that you get enough directionality from your mains for bass, and you might as well use all the subs you have to complement each other, and have them work together. If they are playing something that actually has stereo bass separation, you can end up getting unpredictable interactions between the different channel subs.
I only have two subs, so the equation might change if you have 4, but I reluctantly went mono subs after trying a stereo setup. Specifically, one of my subs had a deep null at 90hz, and running them out of phase with each other did a swell job of fixing that null. If there was actual stereo separation, the frequency response would be unpredictable, depending on if the two subs are playing the same music. It seems like most modern music is mixed to have mono bass anyway. Ditto RIAA (?).
Try, and hear. A pure sine wave will be difficult to detect where it comes from, at any frequency. You may be able to hear the speaker, because any harmonic distortion or noise or vibration from the speaker will stand out unmasked, when there is no other sound present at higher frequencies, that would otherwise mask the distortion. Pure 60Hz will only be possible to detect at close to 90 degrees horisontal, with no other masking sound present.
- Joined
- Jun 5, 2020
- Messages
- 5,356
- Likes
- 4,337
In most installations the response from each subwoofer unit will be different, and the sum of all subwoofers will be different from those again, which means you will not be able to get a similar response for only L, only R and L+R. Bass will be different depending on which channel it is mixed into.
Beat me too it ... Nobody puts @amirm in a corner either, unless you want to read 30 pages of circular back and forth with heavy doses of appeals to authority...
Agreed, and very well explained. Thank you.
And thank you for this nice and positive comment. Being an engineer, I am not much into smalltalk, and I mostly miss any opportunity to leave nice words, when deserved.
In short, whoever said this doesn't know what he is talking about.
You perceive time smear in bass differently to other frequencies, and to effectively trap or modify the response with panels etc is a crazy idea in the real world as the waves are massive. I have used geddes methods with as many as 8 subs and it works very very well. Walking around the room lead to no perceivable change in bass response unless you put your ear up to a specific sub.
I would also describe the subjective 'sound' I achieved as what many would describe as 'tight' or 'fast'. At the time, this was not what I expected as I was in the 'sealed subs make tight bass' camp. I now know better. What caused this was the fact that sealed subs tend not to play the lowest frequencies (at least not without EQ).... which in my room, it turned out I had a room mode at!
Last edited:
Not all engineers are good at distilling complex ideas down to concise statements.
Tried this.
You will likely detect its direction, especially at high SPL. But that's because the harmonics will be audiable, not because you can localise 60hz.
Solution? Use JBL 2242h subs. (Or 3 like me!)
Downside? You'll not be hiding this purchase from the missus...
Here's the port of one of the subs....
Agreed. "Smooth" bass = "fast" bass. It is the peaks which stick out like sore thumbs, in part because they take longer to decay into inaudibililty (and sounds which last longer are perceived as being louder).
Last edited:
