look up the size of a 30hz wavelenght.
nearfield bass is impossible in a small room. you hear just as much the reverberant room as the direct source
8" subs
LOL
sure its a sub if it extends down to 30hz. problem is ditortion at extremely low spl.
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May we all take comfort, in that facts....... anything anyone can empirically prove for themselves......don't depend on individual persistence
I don't own any 15" subs. A 15 is a midbass to me.
Wrong. You made the claims I questioned, so the burden of proof is on you to back up your assertions.
You're asking me to prove a negative, a logical fallacy. But I'm really not expecting more than this sort of logic from you at this point.
That's nice to know as we potentially have a project coming up for a customer that's going to use 18" IPALs. I'm sure he'll find that pic reassuring...
Reflections can actually be at a much lower level (and even a few db can be significant) - particularly as freq.s lower. You will of course still hear the reverberant field, but direct sound can *dominate.
*and that dominate direct sound is not providing substantivly improved localization (though you wouldn't want that anyway - you don't want to localize reproduced sound at the source).
It can be *compared, but what should be noted is that a typical subwoofer can and will reproduce substantive spl in the room (reverberant field) whereas the headphone will not. (..not that the headphone won't reproduce sound in-room, but that it will be so low in spl as to be not at all substantive.)
*a stereo pair of 12" "sub" drivers right next to a listener's head run dipole will be far more similar to the headphone result vs. a monopole right next to the listener's head; still - even the monople can have substantively **higher direct sound at the listener's ears as freq.s lower assuming the proximity is very close to the listener's head.
**it's also a cheap way of extending the output near the average for typical "sealed" (monopole) subs, allowing for higher spl at lower freq.s along with lower excursion/distortion. (..where most sealed designs have that quasi 12db an octave loss below box resonance that effectively get a "boost" at those lower freq.s.)
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-close proximity can help alleviate that problem. Multiple drivers as well.
Honestly, it doesn't matter what the size of the driver is - what matters is the result in actual use, and what matters *most is the subjective result to that listener.
Bandwidth vs. Spl (notably fighting against compression losses rather than looking at high **non-linear distortion) - same as it's ever been.
**a lot of larger pro "subs" also have very high non-linear distortion near Fs. Regardless of size, it's always a cherry-pick process to achieve something a bit objectively better (and subjectively as well).
Somewhat ironically the pro industry where you will see most 15/18/21 inch subs - aren't actually designed for use much below 30 Hz (and those drivers rarely have Fs below 28Hz, and most about 32Hz). Home Theater on the other hand is often concerned with lower than 20 Hz, and there the most typical size is arguably 12" drivers (with driver Fs closer to 20 Hz). Of course most HT sub's are also bass reflex designs extending the result close to 20Hz regardless of the driver size.
*it's amazing how often we forget this when looking for "absolutes" and objectively superior results.
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^something like that 24x 10" story:
I was conversing with Bert of BD-Design once about his sub-horn: where he flat-out said that you can only get excellent bass with a sub horn (I think Jean Michael also said as much to me once). My response was that it's often about excursion and the driver chosen - with enough of the right drivers in a similar size (or even smaller) volume as compared to his massive sub-horn(which was built into the room): he could in fact achieve similar sound (and perhaps better than) to what his sub horn produced, and potentially with less time/phase delay.
-a few years later his sub horn enclosure is no longer a horn, it's a bunch of drivers (in what I believe is a multi-sealed system). (..if nothing else, I'm sure it's a better result with extreme low freq.s when compared to the sub horn - which recording-dependent can offer more subjective "expansion" of the sound stage with those extreme low freq.s.)
If he had made them separate (to be distributed in room for best results), he might have achieved something more (depending on room and operation bandwidth) than even what he has now.
http://www.davidgriesinger.com/asa05.pdf
I was conversing with Bert of BD-Design once about his sub-horn: where he flat-out said that you can only get excellent bass with a sub horn (I think Jean Michael also said as much to me once). My response was that it's often about excursion and the driver chosen - with enough of the right drivers in a similar size (or even smaller) volume as compared to his massive sub-horn(which was built into the room): he could in fact achieve similar sound (and perhaps better than) to what his sub horn produced, and potentially with less time/phase delay.
-a few years later his sub horn enclosure is no longer a horn, it's a bunch of drivers (in what I believe is a multi-sealed system).
(..if nothing else, I'm sure it's a better result with extreme low freq.s when compared to the sub horn - which recording-dependent can offer more subjective "expansion" of the sound stage with those extreme low freq.s.)If he had made them separate (to be distributed in room for best results), he might have achieved something more (depending on room and operation bandwidth) than even what he has now.
http://www.davidgriesinger.com/asa05.pdf
I just don't see how reflections will be close to the same loudness as the direct sound right at the sub. I mean there is path loss in everything that I know about, sound, RF, light. The sound leaves the sub travels to a wall, bounces and returns to the sub. It has traveled two paths, to the wall and back how can it have the same level as when it left the sub?
Measure a sub at 0.25M or across the room. In the first measurement you'll predominantly see the sub, in the second measurement you'll predominantly see the room. I've done this hundreds of times over the last 30+ years.
I'm not sure lousymusician has ever done this measurement.
I'm not sure lousymusician has ever done this measurement.
my measurements dont improve the closer i bring my speakers into my room. where did you get this?
if you think you can hear 30hz in your room before it has been reflected by the room, be my guest. its well known why its impossible.
Want good bass performance?
25-20 inch thick bass traps, in as many corners of your room as possible (make them reflective of HF using kraft paper in front of your bass traps)
15" woofers in 150L cabinet
if you have both, hard to go wrong in terms of bass.
if you think you can hear 30hz in your room before it has been reflected by the room, be my guest. its well known why its impossible.
Want good bass performance?
25-20 inch thick bass traps, in as many corners of your room as possible (make them reflective of HF using kraft paper in front of your bass traps)
15" woofers in 150L cabinet
if you have both, hard to go wrong in terms of bass.
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that depends entirely on said room.
in a anechoic chamber, getting further wont make measurements worst.
and really, even in a untreated room, a 15'' woofer in 150L cabinet will make good bass. Bass traps are icing on the cake: not necessary for satisfying bass if you have 15'' woofers...
what really matters for SQ is treating your early reflections (lower mids to treble). THOSE matters way more to the SQ.
in a anechoic chamber, getting further wont make measurements worst.
and really, even in a untreated room, a 15'' woofer in 150L cabinet will make good bass. Bass traps are icing on the cake: not necessary for satisfying bass if you have 15'' woofers...
what really matters for SQ is treating your early reflections (lower mids to treble). THOSE matters way more to the SQ.
my room is treated
behind my listening position, on the floor, ceiling and side walls, theres 10'' thick absorption panels.
the best speaker position was indeed directly on the wall. if I bring the speakers nearer my listening position, i get worst dips and peaks in bass in Frequecy Response measurements
its a bit of a myth that speaker are best away from the front wall. best speaker position is often as close as possible to the front wall (or very far min 5-6 feet) or even better, mounted into the front wall.
https://www.genelec.com/monitor-placement