The consensus seems to be that 3 subs is good enough and 4 is perfectHi all,
I'm eager to try the 3subs method.
Did anyone experiment further - by using 4 or more subs? There is not much information about that so one might think 3 are more than enough?
Thank you!
. More than 4 is seldomly needed other than for max output. It helps to have dsp for each sub and optimize it's settings using software, see this thread on diyaudio and this (a lot more active) thread on avsforums
Hi,
Thank you both for the feedback and useful links!
I'm reading this thread now and I'm on page 64. So far there is no information about using more than 3 subs. I will keep on reading, of course.
Glad to hear 4 is perfect! Luckily the subs have integrated 8-band EQ with HP and LP options. I hope this would be helpful.
I've been struggling with bass issues for quite some time now but I didn't try random positions yet. I'll be really happy if this approach would give positive results beacuse I was starting to think my room is somehow cursed.
Thank you both for the feedback and useful links!
I'm reading this thread now and I'm on page 64. So far there is no information about using more than 3 subs. I will keep on reading, of course.
Glad to hear 4 is perfect! Luckily the subs have integrated 8-band EQ with HP and LP options. I hope this would be helpful.
I've been struggling with bass issues for quite some time now but I didn't try random positions yet. I'll be really happy if this approach would give positive results beacuse I was starting to think my room is somehow cursed.
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There is no general solution to number of subs, location, or quality trade-off. For me, one great sub, even with slight, probably unbearable, FR irregularities is better than 4 poor ones.
Might as well buy an inexpensive DSP, even if only for testing. Use the average of 3 mic plots setting the 3 around where your head would be. Check out sub locations for best response at your head. Simple.
B.
Might as well buy an inexpensive DSP, even if only for testing. Use the average of 3 mic plots setting the 3 around where your head would be. Check out sub locations for best response at your head. Simple.
B.
Well, 5 years ago I would agree with you. But there are some rooms, obviously mine as well, where one sub is just not going to do it. I generally agree a greater sub could perform better but there are many threads on AVS forums where 4 cheaper/smaller subs did yield better results.
Once I was able to get pretty good response (+/- 5dB) with 3 subs but low frequencies were still not as good as in my previous place with just one sub. I guess time domain or decay times were still not where they should be. Not really sure because this is currently beyond my knowledge.
Once I was able to get pretty good response (+/- 5dB) with 3 subs but low frequencies were still not as good as in my previous place with just one sub. I guess time domain or decay times were still not where they should be. Not really sure because this is currently beyond my knowledge.
With one superior well-located sub you can get loud, clean, and low. Why give that away for 3 subs that gives your eye the illusion of flat FR that may not be audibly and flatter to your ear?
Unless you have lots of the time, money, and skill, that may be the trade-off.
B.
OK, based on my experience I don't believe one sub is enough, no matter where it is and how expensive it is. I might be wrong here, so please, do tell more. Did you manage to achieve that in more than one room? What kind of sub was that?
What I was trying to say that I managed to get a decent bass with 3 subs but it was worse than in my previos place with only one sub. No measurements there, just my ears. I believe a room plays an important role. Rigid vs porous walls, dimensions, seating position ...
What I was trying to say that I managed to get a decent bass with 3 subs but it was worse than in my previos place with only one sub. No measurements there, just my ears. I believe a room plays an important role. Rigid vs porous walls, dimensions, seating position ...
It's been almost two years and I thought then I tried everything.
I'm going to start over and see what happens. I've learned some things while reading this thread.
My last good result was two subs between main speakers and one behind seating area.
One sub between mains and two behind seats (next to the sidewalls) were also not so bad.
Why does a corner position have a bad reputation? Isn't that one of the starting points in the "Geddes" approach?
I'm going to start over and see what happens. I've learned some things while reading this thread.
My last good result was two subs between main speakers and one behind seating area.
One sub between mains and two behind seats (next to the sidewalls) were also not so bad.
Why does a corner position have a bad reputation? Isn't that one of the starting points in the "Geddes" approach?
I'm reading the articles by Dr. Geddes and others with great interest. I have a lot of reading ahead of me.
So far I've figured I might need more damping. The in-room response is ragged.
I fear that nothing however will solve its almost cubical shape, except maybe opening some doors and windows...
Has anybody tried installing aperiodic vents in the room? I figure that if it works for an enclosure it might work for a room too. Correct me if I'm wrong.
Back to reading...
So far I've figured I might need more damping. The in-room response is ragged.
I fear that nothing however will solve its almost cubical shape, except maybe opening some doors and windows...
Has anybody tried installing aperiodic vents in the room? I figure that if it works for an enclosure it might work for a room too. Correct me if I'm wrong.
Back to reading...
The general rule of thumb for multiple subs is that the FR variance (variation) will go down as 1/N where N is the number of subs, but a few caveats apply. Thus two subs will have half of the variance of one, and three a third of one, a fourth a quarter. Hence a fourth sub adds only a few percent improvement over three - but sometimes that's just what is needed. Since I don't use a crossover to the subs from the mains in much of the band I have five subs.
Now, if I have all four subs in the corners then because they are all basically in the same positions they will not go as 1/N, but slower.
Now, if I have all four subs in the corners then because they are all basically in the same positions they will not go as 1/N, but slower.
Looking at the single source case, a corner source couples well to resonances that involve going out into the room and returning. This is not so much the issue with higher frequencies or with the lowest frequencies.
But you're still suggesting one should be in a corner?
By the way, what is your opinion on delay vs. phase setting? I know these are basically the same thing but the way I see it phase varies with frequency and that makes delay more accurate.
Apparently it takes a number of cycles, 4 or 5 (?) minimum (obviously many more at higher frequencies) for the brain to determine a particular frequency, by which time low frequencies will have bounced around the average listening room a few times, so I doubt delay or phase will matter very much.
Corners are fine, let's face it they are often the only choice. Two of my subs are in corners. At least one should be in a corner, as long as its not a solo sub.
As to delay, I don't think it's necessary. Phase, of course, is a useful variable, especially +-. I have not found the need for phase otherwise. It's all about getting the best end result as provided by measurements. If phase or delay gets you there easier then go for it. One thing that I will say from experience is that the effects of phase or delay are quite unpredictable. If I have a peak in the summed response from all drivers then it is far easier to correct with a PEQ filter than phase, because phase will change the way everything sums up.
Try this sometime - find a good end result and flip the phase of just one unit. This will change the result in ways that you would never expect. I've outlined the procedure many time before so you should refer to that.
Timbre is the psychoacoustic perception of FR (which is an objective measure,) but the two are intimately related. They are just different terms for different perspectives - one subjective and the other objective.
Are those front corners?
Very interesting! AFAIK most of automated (room correction) systems require putting the phase to 0 and polarity to +. Only then they can 'integrate' multiple subs with delay settings. This is the first time I hear dips should be solved with a PEQ. But that again, my knowledge is only basic so I'm happy to learn!