I think most bookshelf speakers, just like most tower speakers, begin at a disadvantage in terms of providing good bass response at the designated listening position regardless of the size of the bass drivers; which is that the drivers for all frequencies are positioned in a single cabinet in some sort of fixed alignment. The bass drivers acually require their own cabinets and the capacity to be independently positioned in the room in relation to the listening position, in order for bass performance to be optimized. Ideally, these independent modules would also have independent controls for volume, crossover frequency and continuously variable phase settings, just as good quality traditional subs possess for optimizing performance and seamless integration with the midrange/treble drivers on the main speakers.
The main issue with this is that the optimum position for the midrange and tweeter drivers, in relation to the listening position, for midrange/treble and imaging are highly unlikely to be the optimum position for the bass drivers in relation to the listening position.
If good bass response at the listening position utilizing the much larger bass drivers of tower speakers is highly unlikely because of the above, I see absolutely no reason to believe that using smaller bass drivers, even multiple smaller bass drivers, would be expected to perform well.
However, I'm certain that even a good quality pair of subs with 10" drivers are capable of vastly exceeding the bass performance at the listening position than the bass drivers on most bookshelf and tower main speakers are capable of providing, regardless of their size. The primary cause of my certainty is the tremendous bass performance advantages gained from the independent room positioning capabilities of sub drivers and subs.
One of the main advantages is ensuring that there are no bass room modes (room locations with obvious bass peaks, dips or nulls) at the listening seat. It's easy to check if your current listening seat is positioned at or near a room bass mode; just listen to the bass response at locations near your listening seat and check if the bass quality varies at various other spots in around your room from.
Tim
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Kenjit
I don't know what I like most about your posts, the personally insulting tone or the flat earth perspective you have on science and engineering.
Best,
Erik
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I finally got the bass that I really like. It is from a folded horn design that is only 40T 15D 10W. It uses an 8" driver, but here is the kick. I had the pleasure of being able to try different drivers in this cabinet. One of them was an Audio Nirvana driver which is a respectable driver when used in the right cabinet. This marriage wasn't good at all. Muddy bass. No problem, I went to a Mark Audio 12P 8" driver. Here is what bothered me. The actual cone area is 4 3/4". Crap, says I, why even try it? In short, it produces incredibly accurate bass in my room as deep as I want. Don't understand all the physics, etc, but I have no desire to try the next driver (8" Silver Flute). Size matters, not here. |
ive compared hundreds of speakers at this point, ive never heard any 6 inch 2 way sounds anything but a toy vs a pair of real Tannoy, JBL, or whatever big speaker. so you either drive a lawnmower or a ferrari, your choice
treating the room instead of trying to compensate the bad room with a limited speaker is the path to long term satisfaction ime
someone mentionned the alpair 12p, I loved my pair when i had them. but to say it has tremendous bass just goes to show how relative this hobby is. jbl l300 has tremendous bass, not alpair 12p |
The Alpair 12P would likely fail in bass response given a conventional cabinet, i.e. ported, bass reflex, sealed box. I was actually expecting that sort of performance from them regardless of the fact that they were being mounted in a folded horn. If I had no experience with folded horns in the past, I would come to the same conclusion as you. FWIW, I owned a pair of JBL 4343, you know, the ones with 15" woofers? Never could get decent bass performance from them. Owned them in 3 separate houses, with different amplification too. Yah, I wouldn't have believed it either. |
treating the room instead of trying to compensate the bad room with a limited speaker is the path to long term satisfaction ime
I agree. |
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treating the room instead of trying to compensate the bad room with a limited speaker is the path to long term satisfaction ime"
I believe the same and it makes a lot of sense to me. I hope we're all correct, since I just spent about $3,500 in GIK acoustic room treatments which should arrive and be installed in about 2-3 weeks.
I'll let you know,
Tim |
I’ve been a long-time fan of Merlin VSM two ways. The VSM employs a 6.5" Scanspeak 8545 in combination with a line-level equalizer that boosts LF output by 5db, providing useful output into the low 30s. I’m following @theaudiotweak with an order for early-production Purifi 6.5" to try in the VSM cabinet as an alternative to Scanspeak. Early reviews of the Purifi suggest that this driver is capable of lower LF distortion and better dynamics than any 6.5" to date. Its sensitivity, frequency response curve, and dimensions are not too far off the 8545 to be a "drop in."
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noble100 I don’t like organ, so forget 20hz (I went for that like a nut when younger). I love Jazz, the low instruments are piano say 30hz, double bass say 40hz, many instruments no lower than 60hz. I know where each musician, each bass player is standing, where the trombone is, ... the thing about Bass is, despite all the proven physics, listening to my pair of 37 lb 15" woofers each with magnets 7" thick, they can control the bass as much as make it. And, better controlled 40hz gives better controlled overtones 80, 160, 320, ... (overones is why analog sounds more involving than digital IMO) Bass IS or, CAN BE directional. this is a sweet listen, I just got a fresh copy for Christmas). https://www.amazon.com/Double-Bass-180-NIELS-HENNING-PEDERSEN/dp/B005CJQR8S/ref=sr_1_1?keywords=double+bass+pedersen&qid=1579746066&s=electronics&sr=8-1 Keeping bass, or as another member here clarified, the bass overtones directional is why I do not like ports. If ports, front facing. Now lets get to producing bass without roll off, keeping it at proper volume to adjacent, other instruments. This is where smaller woofers cannot perform. Sooooo, if getting some decent bass, IN YOUR ROOM, from 6", then a pair of DIRECTIONAL subs, located adjacent to the mains, Not too big (that’s why I mentioned i.e. 10"), can extend a STEREO experience to relatively equal lower bass!!!! A single, or too large pair of subs, poorly located because too big, will lose the potential for directionallity, and lose the directionality the overtones of those fundamentals provide. You are hearing 40hz at proper level to other instruments, by itself perhaps not directional, but it’s 80 and 160 and .... tell your mind where that 40 is originating! Especially if the fundamental 40 is tightly controlled, thus big magnet, servo, ... |
Bass IS or, CAN BE directional. *Hmmm* It’s very ’circumstantial’....and driven by frequency and the space it’s in. "Now that I’ve got your attention..." *G*.... ’Directional bass’, or the perception of it being such, is ’normal’ (IMHO....oh, forget that...IM not so HO....) for those used to ’direct radiating speakers; who then add ’sub(s)’ for ’punch’ and/or to fill in what they know should ’be there’ in ’that music’ (genre driven...bass guitar, drums...those sort of instruments). As an ’omni’ sort of guy, who lives with ’sound in the round’ (so to shriek)....who also has dipoles (AMT drivers and a pair of Maggie’s) along with ’direct radiators’ for ’reference’s sake’.... ...and a single sub. Small...6ish", ported, self-powered. Frequency, as it lowers, undergoes a ’phase change’ of sorts. It becomes less directional and begins to ’omni’. It’s beginning to respond to the physics of sound waves, and how they behave. Let me illustrate with a analogy, based in the physical properties of air...which acts like water. They are the same thing, basically. You’re just able to walk around in one.*G* You ARE a ’fish out of water’....in the midst of a ’phase change’. Think of sound’s frequency in terms of ’speed’; higher=faster, low=slower. Speed zips past one in a given direction, bounces off of anything in it’s path, and dissipates. Slower, it tends to create vortices, swirling like the air over a stalling wing, ’losing it’s way’....and hangs around, due to the length of the waveform. Now...consider this... Listening to your equipment...(and I could care less what it is, how sophisticated it is or isn’t)....you are IN an enclosure. Being driven by units within their enclosure.... Which does indicate that ’the room’, in many ways, is just as (if not more) important to what you hear and how it’s perceived. ’Upper bass’ can seem ’more directional’ than ’Lower bass’ because, due to waveform, it is... and is effected by the space it’s in. An example: Ever notice, when approaching a venue in which the band is already playing...that you notice the low bass notes before anything else? You go from ’omni’ to ’direct’. (Then you buy a drink, and stop paying attention. *L* I do it, too....) ;) (I Know this is going to start ’something’, but I just had to go there...*L*) |
@erik_squires ....it didn’t register in my small, swelled ’n itchy brain, But....*G*
I Finally noticed that not only that the SNR-1’s have a ribbon tweeter....but "...using a pair of parametric notch filters...." was noted by yers unruly.
Not surprised that those speakers can be ’tweaked’ to ’go flat’.
My octave ’stand alone’ eq’s can’t do that....but the xover and the ’puter’s eq program can...;) Both have parametric functions....
One of these days I ought to try to get an acceptable noise out of a Coke can....*L* I have enough eq at hand and on demand, I could probably excite a pineapple....*smirk*
(Sounds like one ’ell of a ’bar bet’.....) |
AMTs, not true ribbons.
Note though that they are cuts, not boosts. The point of the post was the speaker + room gain creates a lot more bass than we think. Also, don't discount the bass traps I have. :) It would be a much more complicated picture otherwise.
Best,
E
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...and best back to you, Eric. *S* And, yes, I noted the cut vs. boost detail...it's all in how the parametric is set. This I'm confident you know of this....;)
I've got an old SAE '2 band' (high & low) 2 channel set up in my shop area to tame my 'low rent' arrays into a 'reasonable' affair. Beats trying to massage the receiver's tone controls to be acceptable. *G*
I will concur...an AMT is not a true ribbon, but they are less finicky and durable. That, and they can go down to 500 hz before loosing 'credence' at least to my ears...
I don't discount your traps, oh no. My current space makes such impractical; this Will change in the short future. At that juncture, I shall respond in my typical 'knee of jerk' Xsperimental fashion. *G*
I have 'something' I want to try....;) My take on 'nothing ventured, blame yourself' department.
That, and a spouse that absolutely refuses to live in a 'studio'...so I have to be...'artful' about it...;) Blobs (or even GIK panels) 'don't fly' well about her...(she's quite aware of 'hi-fi devious tricks' from living with me for wayyy long time...).
Subtlety in the Long Game. And it works best if not permanent, so one can beat a hasty retreat....;) We both (she & I) have our reasons..... |
....my 'semi-consciousness' dredges up the odd 'musical interlude' from time to time..... Last night, This:
https://www.youtube.com/watch?v=I3W1-Pco9Uk
I have no control over this....*G*....but I'm happy it did. ;) Substitute 'Vivianne' for 'Marion' and Bob will appreciate the return to 'accuracy'....;) Best, and better, J |
My speakers do have good low end, but compared to my cerwin vega D9’s, it’s not even close.
currently use Energy rc-70s’, bass is descent and right, fills my room nicely.
it is a huge front room, with vaulted 16” ceilings, sound is great!
Drug up my old 1986 cerwin vega D-9’s
not even close, not in the same town!
vega 15”’res are so tight, precise, deep, and loud, sure with specific music the Energy’s shine, then hook up the Vegas w Travers, derringer, king diamond, foghta, it’s not even close.
But I love my Energy’s, they are my grail towers! |
It's the flat earth perspective Erik, no-one thinking properly could possibly be as obnoxious or noisome so consistently.
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I have found that the reason to use an active sub is not primarily to extend the bass frequencies, but because it adds greater transparency to the overall sound. I also find that it enhances the quality of the bass, and so it also helps with floor standing speakers that reach down adequately on their own. Why is this? I have no idea, but I heard confirmation of this from more experienced audiophiles. Perhaps it's because the active sub provides a sort of "bi-amping" for the lowest frequencies. |
The bass response is impacted by a bunch of factors, driver design, cabinet design, listening environment volume, and a whole slew of other things.
My preference is a smaller driver since there typically isn't as much mass. I typically get good results in my environment with 10 inch drivers.
But a 6 1/2 woofer is capable of playing 30hz in a small environment like a car.
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There's no replacement for displacement.
You can get some very good low end with small drivers in a transmission line enclosure. But you can't get level and transient response. Can't do it.
Which is why you want sub-woofers. And not just one or two. Each sub creates standing waves in a room. So the frequency response is uneven throughout the room. So what you want to do is to have multiple subs, so that their respective standing waves even things out in the room. I have three subs for that reason.
If you want more level, you need bigger drivers. If you don't need higher levels, you can get away with smaller drivers. My subs have 10" drivers for instance, but with three of them, it meets my needs. |
I have two sets of speakers with 2 pairs of six inch drivers. They are great, but in my current listening room, my 25 x 30 living room with high ceilings, subs are a must on much music. One pair is duplicated in my 12 x 12 bedroom with no subs needed, even without tone controls. I have actually considered using a big sub cabinet wired for stereo sets of 6.5 inch drivers, maybe 3 or 4 per channel, depending on the leftover crossovers I am still playing with.
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My pair of EPI Model 5s agree with you. If you set a speaker up right, usually explained in the owner's manual, you get what the speaker was designed to do.
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I agree with Erik, not based on measurements, but my own ears. I do all my listening via a complex desktop audio setup. I've had 5-6 different powered speakers + passives here, and the top of the heap is the ATC SCM12 Pro passives.
These have 6" woofers and easily the best tweeter I've ever heard. The bass is astounding, also the volume and fullness of sound. I do have a sub (always did) which handles notes below 70 Hz. But down to that cutoff, the bass is concussive & very detailed. The mid-bass in particular is rich & full, just like real music.
Until the ATCs I wouldn't have believed bass this good could come out of a 2-way. |
I think it’s worth noting that the prototype Magnepan “30.7 for condos” recently shown uses multiple smaller woofers for its bass component. All the options available and that’s what they chose. You can argue that the company is trying to keep up with the speed of its ribbon driver, but that responsiveness strikes me as a plus itself.
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I love the bass that comes from the dual 2.5 way 6.5" drivers in my ProAc Studio 148s. Additionally, using some foam bungs to tune the downward firing ports and Soundocity outriggers really puts out the experience I've been looking for before I got these. |
+1 for Soundocity's outrigger! Really makes setting up speakers a lot easier.
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@jfuquay, Magnepan is indeed using multiple small woofers in it's 30.7 For Condos model, eight 6.5" per side to be exact. But they are mounted not in a sealed or ported enclosure, but in an open baffle frame. Can't wait to hear 'em! |
Reminds me of a debate between Paul Klipsch and Edgar Villchur at a national meeting of the Acoustical Society in NYC during which Klipsch said something like "I don’t care if you push it with a broom, you still have to move the air" arguing radiating surface v excursion.
In the process of setting up my subs I was surprised that the display revealed the in-room response of my KEF Reference 1s extended to 30 Hz before dropping sharply. I supplement them with a pair of Velodyne HGS-15s crossed 4th order at 40 Hz.
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I have a highly-damped bedroom with a pair of (terrible?) inexpensive speakers with 6 in. woofers (vented). The highs aren't great I'll admit -
as in not very smooth. THAT is the real challenge- the upper mids and higher frequencies never sound "just right" without some major technological effort (and the associated expense). But the bass coming out of my cheap speakers is remarkable. Jazz bass is very clear, and pipe organ is pretty good as well. In the "other room" I have a very large pair of speakers with built-in powered 15in. subs, so I think after 30 years of listening and upgrading I know what bass is by now. I agree- an 8 inch (or larger) driver is quite a bit better, but your room and your choice of music will either make your listening a relaxing experience, or you'll be reading "Magico reviews" and saving up for the day you can afford a pair. IMO outboard Subs are for movies anyway, unless your room is enormous.
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french_fries:"
IMO outboard Subs are for movies anyway, unless your room is enormous."
Hello french_fries,
I suggest that your belief that outboard subs are only for movies, is a very clear indication that you've never heard a high quality 2-channel music system with well integrated subs or that you lack the knowledge to properly implement subs seamlessly into your own system, perhaps both?
My intent is not to overly offend you, my intent is to suggest that you may not be aware of what you're missing. It's been my experience that the main characteristics that differentiates listening in person to music played live (I'm referring mainly to a smaller type settings and not to large arena type settings) and listening to music on most home audio systems, are the the accurate, detailed and highly dynamic reproduction of the bottom 2 octaves of deep bass (about 20-32 Hz)that is experienced as being felt as well as heard.
Sure, the bass can still be perceived as very good without the bottom 2 octaves but it's not the same powerful, dynamic experience that is felt as well as heard and closely resembles the deep bass of music heard live and in person.
There's also the issue of, even if one utilizes large main speakers with large woofers (or even multiple large woofers) and the speakers are rated as having accurate deep bass extension down to about 20 Hz, this does not mean this deep bass is necessarily perceived at your designated listening seat. This is due to what I mentioned earlier in this thread;
basically that the main speakers are precisely placed in the room with the midrange/treble transducers positioned in relation to the listening seat for very good midrange, treble and imaging performance. The major problem is that the woofers are affixed in place in the same cabinet, typically below the midrange/treble speakers, and cannot be independently positioned in the room and in relation to the listening seat which is required to optimize bass performance at the listening seat.
It's highly unlikely that the optimum performance room positions for the main speakers' midrange/treble and bass drivers, in relation to the listening seat, all just happen to be at the same exact floor spot in the room, with all speakers vertically aligned in the main speakers' cabinets. Outboard subs, being capable of being independently placed in the room and in relation to the listening seat, are ideal solutions for attaining high quality bass response performance at the listening seat.
Using large speakers with large woofers and the midrange/treble drivers in the same cabinets, there's no guarantee that room bass modes (causing bass peaks, dips and nulls) won't exist at the listening seat. Outboard, independently and properly positioned subs will guarantee there are no bass modes at the listening seat.
French fries, if you'd like
I can describe exactly how to utilize 2 subs in your system/room to attain very powerful, dynamic, detailed, fast, smooth and natural bass performance at your listening seat that integrates seamlessly with whatever main speakers you have. If you're open to using 3 or more subs, I can describe how to get near sota bass performance throughout your entire room, not just at your listening seat.
Let me know,
Tim
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’Cutting Edge Design’ starting with your existing 6" drivers. look at the directional pair of monster woofers at the bottom of these 22k beauties: https://www.audiogon.com/listings/lis9i01e-evolution-acoustics-mm2-full-range?utm_campaign=Saturday_Email_20200125&utm_content=saturday_email_20200125&utm_medium=email&utm_source=zaius Your existing mains, (6" driver or two): Probably in cabinets or stands to get the tweeter at seated ear height. No way to get a directional pair of woofers matched with their l/r origin. Cut your tall enclosure, reseal the bottom, put it on a self powered sub-woofer, same l/r. Or, toss the stands, put them on the pair of sub-woofers. Of course you need to figure out vibrational connection/isolation, but that’s easy isn’t it. Hah. Mains with tall cabinets ’shortened’ will have less volume, BUT, the 6" no longer trying to produce bass, so, larger volume, or disruptive or non-directional port not needed. As I Punned, ’Cutting Edge Design’. |
In Chicago audio show (2016) I have heard, rather small tower
speaker, from Penaudio (Serenade) with two 6" woofer, and it was unbelievable bass ! |
Today is a paradox for audio systems. Back in the day when sub woofers only existed in passive systems with large cabinets we were still happy. Purests in that time of the late 60s, 70s, 80s tried to sell systems with no tone controls as they do today. We were told it would "color the sound" people liked the loudness, bass and treble controls. Today if you want bass you are told to buy a sub woofer after spending a anywhere from $500 -$1000 for a pair of speakers. Guess what? The sub woofer colors the sound.
I have a relative the worked as a speaker builder for paragon a acoustics back in the 80s. He built himself a pair of 6" driver towers. They used 6" woofers. Why? They not only got the bass below 30z, but were two way because the smaller cone could also get good midrange. Also, smaller drivers are easier for a power amp to control because of less moving mass. They are fast a d respond quicker to changes in music dynamics. Also because of that, less distortion. No sub was needed. They still sound great |
I had some computer hardware issues that are now rectified but I was unable to continue following this thread as closely as I was over the past 3 days.
Catching up today, I was disappointed to discover that a few posters have been attempting to debate some facets of how deep bass soundwaves behave in smaller domestic rooms and how our human ears and brains detect and perceive these deep bass soundwaves as deep bass. I just want to restate and remind thread readers and posters of a few things that have been scientifically proven by acoustic experts and are generally considered to be true by the vast majority of them. In other words, facts that we should not be wasting our time and effort by debating or misleading others about:
1. The vast majority of humans are unable to localize bass sounds/tones below about 80 Hz. This means an inability to determine where these omnidirectional deep bass soundwaves/sound tones are originating from and, therefore, means there’s no need or sense to operating deep bass drivers (including subwoofers) in any other mode than mono since there is no such thing as stereo deep bass. This is why virtually all commercial music recording engineers sum the bass at about 80Hz or below to mono on their recording mixes. Even if a system were configured for stereo bass below 80 Hz, it would be useless since there’s virtually zero music source content material to play on it. If you doubt this, try to name even a single exception to this statement.
It’s very important to note, however, that most individuals will still be able to perceive the deep bass sounds/notes as directional and properly localized within their system’s soundstage illusion. That is, deep bass sounds/tones will be perceived as coming from the proper instrument position within the stereo soundstage.
This is due to the fundamental deep bass tones, being below 80 Hz and coming from the bass drivers, not being directional but the overtones/harmonics of the fundamental bass tones, being above 80 Hz and coming from the main speakers, being directional and our brains being able to associate the directional overtones/harmonics with the omnidirectional fundamental deep bass tones and thereby perceive specifically where in the soundstage the deep bass tones are coming from.
I utilize 4 relatively small, 12"x14.5"x28", subs with 10" long-throw aluminum drivers in a distrbuted bass array (DBA) in my room operated in mono mode from 20-40 Hz with my main speakers run full range with bass extension down to 35 Hz. I can attest that I definitely perceive the deep bass as coming from the appropriate soundstage location.
I not only perceive the increased bass extension and dynamics as seamlessly integrated within the soundstage illusion in my room, this high quality bass also provides the perception that this soundstage is wider, deeper and more open with individual images that are more solid, stable, palpable and natural. I’m able to focus in on individual mages/instruments and follow their musical notes, beat as well as volume and pitch changes. This high quality audio reproduction is easy to perceive in the midrange and treble frequencies, but extending this perception all the way down to the deepest bass frequencies is unique in my experience and something that really enhances my involvement and enjoyment of all the music I play.
2. Humans can’t even perceive the exitance of sound tones in their rooms until the complete full cycle (fully formed) soundwaves exist in the room to be detected by our ears and processed as a perception of sound at a certain pitch/frequency, volume and duration. It also takes several full cycle soundwaves to be presented into the room for changes in pitch and volume to be perceived.
This is simple, matter of fact and routine with the relatively short and highly directional midrange and treble frequency soundwaves in a room but becomes more complex, less matter of fact and routine with the relatively long and omnidirectional frequency soundwaves in a room. As I’ve stated previously, a 20 Hz soundwave is 56’ long, a 30 Hz is 28’, a 40 Hz is 19’, an 80 Hz is 14’, a 500 Hz is 2.7’, a 5,000 Hz is 2.7", a 10,000 Hz 1.4" and a 20,000 Hz is a fraction of an inch long.
It’s easy to see from these soundwave length examples that as bass frequencies get deeper, their complete full cycle soundwaves at some point may exceed the physical dimensions of an individual’s typically sized domestic room and inevitably it requires the soundwave to reflect off of at least one room boundary (floor ceiling or walls) for the entire soundwave to exist in the room.
These long deep bass soundwaves continue to reflect off room boundaries until they’re are absorbed, diffused or run out of energy and invariably collide with other reflecting and more direct bass soundwaves which cause bass room modes. These room modes are perceived as specific room spots at which the bass sounds exaggerated, attenuated or even non existent. Without using at least two independently and properly positioned deep bass drivers reproducing frequencies below about 80 Hz in a room, there’s no ability to ensure your listening seat position is bass room mode free.
The above are proven facts and realities that need to be accepted and taken as givens in any meaningful discussion concerning the attainment of very good bass response performance in any room and with any pair of main speakers. If you just positioned your main speakers at specific room spots, in relation to your listening seat, to optimize the midrange. treble and imaging performance and are also getting very good bass performance there as well without at least a pair of external and independently positioned subs, then consider yourself very lucky since you just happened by good fortune to avoid any serious bass room modes.
Of course, there could also be bass room modes at your listening seat and you’re just unaware of them.
Tim
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Frequency, as it lowers, undergoes a ’phase change’ of sorts. It becomes less directional and begins to ’omni’.
Look up Schroeder's Frequency. It is exactly what you mentioned.
https://www.soundandvision.com/content/schroeder-frequency-show-and-tell-part-1
As you mentioned, there is a phase change, but as with most things, it is not sudden and the lower it goes, the less directional. Try this exercise, have a tone generator to put out 40Hz, and then try locate the speakers, I bet you cannot. at 150Hz (lower than most Schroeder Frequency), you probably can. Also different room size has different Schroeder frequency so everyone's observation / experience might be different. |
Hello jmpsmash, Good post with very accurate and useful information about how we perceive sound at various frequencies in our domestic sized rooms. The Schroeder frequency of a room typically being about 200 Hz , the fact that we can't localize bass frequencies below about 80 Hz, the knowledge that humans can’t even perceive the exitance of sound tones in their rooms until the complete full cycle (fully formed) soundwaves exist in the room to be detected by our ears and processed as a perception of sound at a certain pitch/frequency, volume and duration and it takes several full cycle soundwaves to be presented into a room for changes in pitch and volume to be perceived; these are all very useful concepts and facts to be familiar with for all of us home audio enthusiasts. Okay ladies, now we're having a meaningful discussion about attaining good bass response in our uniquely sized and shaped rooms. Science and facts are our friends, boys and girls. Here's a quote from The Absolute Sound reviewer, Robert E. Greene, that I find very relevant to this discussion: "Audiophiles tend to be very concerned about the upper half of the musical spectrum. “Female vocals” are the standard test material for many. Perhaps this arises precisely because it is the upper-frequency material that does not change so much from one room to another. So, if one thinks of audio as mainly about a system of equipment rather than about the combination of that system and a room (as is really the case), then it becomes natural to concentrate on the part that is affected least by the room. Unfortunately for this view, the lower frequencies are a truly vital part of music. They are harder to deal with in a domestic environment than are the upper reaches, but deal with them one must." Dealing with the lower frequencies via the utilization of 2-4 optimally positioned, good quality and optimally configured subs are the best solutions I've ever used to date and that I'm currently aware of. The more subs deployed in a room, the better the lower frequencies are dealt with.
The truth will set your room's bass free, Tim |
I added a chart from Gravesen on my blog, which shows exactly how room gain affected one of his designs.
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Erik,
Your blog? How does one access that?
Thanks,
Tim
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Hi @noble100
It is the link in my first post. :)
Best,
E
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To appreciate what constitutes a good bass, one needs to experience a distributed subs system like the Swarm. Four relatively small boxes with 10 inch drivers placed against the four walls. |
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No there is not. And there never will be.
There is a sense of Bass but not to real scale.
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No there is not. And there never will be.
There is a sense of Bass but not to real scale. I think you missed the point of my original post, @ishkabibil :) |
Schroeder’s frequency does vary from room to room. In general, the larger the room, the lower the Schroeder’s frequency and more directional bass is.
for a typical concert hall, it can be as low into the teens if not lower. So everything is directional, even double bass and the lower/lowest registers in the organ.
And I wonder if that’s why we are never able to reproduce concert hall acoustics in our relatively tiny rooms
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@erik_squires apologies if you have mentioned it. back to your original post. I wonder how big is your room? 6.5" may be good enough for a medium room, but might be a bit lacking if there isn't enough travel to move enough air to energize a large room.
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The standard procedure for installing a 4-sub DBA system such as the AK Swarm, includes the final step of inverting the phase (simply by reversing the pos. and neg. connections on the sub) on each of the 4 subs sequentially to determine if any individual sub's phase inversion positively effects the overall bass performance in the room of the 4-sub DBA system as a whole.
In my 23'x16'x8' room, currently without any bass room treatments and without the use of any DSP or electronic room control/equalization of any type, I noticed no improvements in the overall bass performance in my room of inverting the phase on any of the 4 individual subs comprising my 4-sub AK Debra DBA system.
However, this does not mean that phase inversion on a particular individual sub in other 4-sub DBA systems would not be significantly improved in overall bass performance. I believe only a brief audition of a good quality 4-sub DBA system would be sufficient to convince the most ardent skeptic of this concept's near state of the art effectiveness.
I have no stake in this concept except the $3K I spent to adopt it, my intention is solely to spread the word of how amazingly well it worked for me and will work for anyone else guaranteed, regardless of room or main speakers utilized.
Tim
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@jmpsmash apologies if you have mentioned it. back to your original post. I wonder how big is your room? The total acoustic space is about 12.5’ x 30’, divided lengthwise into a living room and a second kitchen/dining area. 6.5" may be good enough for a medium room, but might be a bit lacking if there isn’t enough travel to move enough air to energize a large room. So, again, the point of the post is not that everyone will be satisfied with a small woofer, but to help buyers understand that even relatively small speakers can put out quite a bit, and that room acoustics matter a great deal. For my modest apartment, with the couch 9’ or so from the speakers this is plenty of high quality bass. Which brings me to another point: Good room treatment can make speakers sound BIGGER. Going with larger speakers in a bad room may in fact be a bad idiea. |
@erik_squires " To appreciate what constitutes a good bass, one needs to experience a distributed subs system like the Swarm Not at all universally agreed to. https://www.soundandvision.com/content/are-you-putting-subwoofers-behind-viewer " The author has no idea how distributed bass works. Both Geddes (PhD thesis on bass) and Welti (Floyd Toole’s Harman lab) found in their research that key to distributed bass is asymmetric placement. Geddes believes three sources is enough: one in the corner, two others haphazardly against other walls. Duke LeJeune, Geddes’s coworker and constructor of the Swarm, adds the fourth source. There is no point adding more sources. Phase switching is not really part of the concept. Digital corrections of the whole system can be applied, but already the haphazard placement does most of the job. Digital corrections using counterwaves, such as those used in Kii3 or D&D, don’t really work below 50-60 Hertz. To battle complex phenomena like room modes, randomness is the most optimal way. Here, one can see easily, what problem room modes can be computationally: hunecke.de | Room Eigenmodes Calculator |
One more interesting concept is dipole bass, proposed by Siegfried Linkwitz in his LX521. The subs are v-frame dipoles and the side wall modes are minimized by cancellations. The bass is incredibly clear and tight.
Finally, one can put the single sub next to his listening position to get at least one good spot with it.
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In your post regarding Linkwitz you prove my point. The idea that only swarms can produce great bass is what I object to.
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Hello pirad,
I was so impressed with your knowledge and posts on this thread, that I looked at your profile and read many of your previous posts on a wide variety of other threads and subjects. They were equally impressive, demonstrating an equally substantial knowledge of the science of the subjects combined with an obvious good measure of practical experience on the wide variety of subjects.
I'm fairly certain my very high opinion of your posts as very high quality are influenced by the fact that I agree with the vast majority of your well worded opinions. I was just curious whether you're associated with an audio industry company or just an interested consumer hobbyist?
Thanks,
Tim
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