Looking for the rules on what defines a true subwoofer. Running many sims for LF drivers in WinISD has been a bit of an eye-opener on just how difficult it is to work models in the sub 30Hz region
Searching for guidelines on the internet re subwoofer definitions and requirements seems like those in the know cant agree amongst themselves. Some say a 3" .1 section from a PC multimedia 2.1 is a subwoofer, while on the opposite end it seems like there might be some consensus around 16Hz and some around 20Hz as the lower end extension to aspire towards
That's regarding frequency coverage. As for SPL requirements. This is more difficult to jot down as most will look at this from their personal requirements
After examining hints and efforts on what knowledgeable types seem to have been involved in, it seems to me that 16Hz is a good-looking number for F0 for a true subwoofer to support background music and effects with cinema for both realism and mood creation
Does this background music carry low bass, or is that mostly in the effects? I don't know, but something to study in the near future. When it comes to non cinema music, the bandwidth covered by the 5-string bass is plenty for me to wallow in bliss, so I suppose that covering cinema well would mean a well covered and full music experience. As mentioned, a good performance with a 5-stirng is plenty to make me happy and well borne out with the fact that one of the smallest THX rated unit, the cheap and cheerful Logitech z623 'sub' has historically been plenty for me with both output and low end
So can anyone set a bar?. What makes for true subwoofer?. I think covering the following would set one bar
(Note, most systems have a volume or Eq of some sort to bring things down to comfortable and acceptable)
A 16Hz F0 with 85dB attained band wide and with a 20dB reserve headroom from F0 to 300Hz can't help but ensure that the music is well covered and most satellite to floor standers well covered. Group delay under 40, but not sure about phase (what would be a good margin here). Some of this is borrowed from THX. And I suppose that rating attained at listening position would determine overall LF system size for the use with the gamers used as one example of use
Music is a tool used in games just like as in cinema. Let's use this gamer example to see how this translates at a listening position of 1m to see if I have my head wrapped around this correctly. In theory, if the subwoofer uses 1w to produce that 85dB at 16Hz at 1m, it would need 100w of headroom in reserve to create 105dB at that same 16Hz and this power requirement would escalate as listening distance increases (what is the correct calculation here?)
Would this be a good definition for a true subwoofer?
Searching for guidelines on the internet re subwoofer definitions and requirements seems like those in the know cant agree amongst themselves. Some say a 3" .1 section from a PC multimedia 2.1 is a subwoofer, while on the opposite end it seems like there might be some consensus around 16Hz and some around 20Hz as the lower end extension to aspire towards
That's regarding frequency coverage. As for SPL requirements. This is more difficult to jot down as most will look at this from their personal requirements
After examining hints and efforts on what knowledgeable types seem to have been involved in, it seems to me that 16Hz is a good-looking number for F0 for a true subwoofer to support background music and effects with cinema for both realism and mood creation
Does this background music carry low bass, or is that mostly in the effects? I don't know, but something to study in the near future. When it comes to non cinema music, the bandwidth covered by the 5-string bass is plenty for me to wallow in bliss, so I suppose that covering cinema well would mean a well covered and full music experience. As mentioned, a good performance with a 5-stirng is plenty to make me happy and well borne out with the fact that one of the smallest THX rated unit, the cheap and cheerful Logitech z623 'sub' has historically been plenty for me with both output and low end
So can anyone set a bar?. What makes for true subwoofer?. I think covering the following would set one bar
(Note, most systems have a volume or Eq of some sort to bring things down to comfortable and acceptable)
A 16Hz F0 with 85dB attained band wide and with a 20dB reserve headroom from F0 to 300Hz can't help but ensure that the music is well covered and most satellite to floor standers well covered. Group delay under 40, but not sure about phase (what would be a good margin here). Some of this is borrowed from THX. And I suppose that rating attained at listening position would determine overall LF system size for the use with the gamers used as one example of use
Music is a tool used in games just like as in cinema. Let's use this gamer example to see how this translates at a listening position of 1m to see if I have my head wrapped around this correctly. In theory, if the subwoofer uses 1w to produce that 85dB at 16Hz at 1m, it would need 100w of headroom in reserve to create 105dB at that same 16Hz and this power requirement would escalate as listening distance increases (what is the correct calculation here?)
Would this be a good definition for a true subwoofer?
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https://alexiy.nl/eq/ and below 16 Hz is infra-bass or at least it was when I was designing seismic rated industrial electrical power and controls' cabinets/systems, though most folks use our 20 Hz acute hearing BW limit as the break point.
Ye, but a professional bartender can often set it better.
True- accurate or exact.
Sub– A prefix that means “underneath or lower”.
Woofer- A loudspeaker designed to produce low frequencies
Yes, 1 to 100w is a 20dB increase, which applies to any frequency.
In free space, in the far field, each doubling of distance reduces output by 6.02dB.
The far field can be reached within a meter for a small low frequency source, but becomes greater for large arrays, once all the drivers sum coherently, the far field is attained.
In an acoustically small room, where low frequency wavelengths are larger than room dimensions (a 16Hz wavelength is ~71feet or 22meters, 160Hz one tenth that) speaker position, the room's modal, reflectivity and absorptive behavior render inverse distance based SPL calculations invalid.
The transition from "hearing" to "feeling" low frequency sound varies so much between individuals that the cheap and cheerful Logitech z623 'sub' that is plenty for you for both output and low end would not be at all satisfactory for someone who appreciates music that extends another two octaves below it's response.
Art
As I opened with, not an easy task to mess with a 16Hz F0, especially when still keeping with the gamer/workstation example with ergonomics and space requirements in mind. After all, this would likely be a domestic, arcade or studio situation. It not that difficult to imagine one day trying to make an impactful promotional video for my boat rentals. Hervey Bay is a major whale watching destination and video is a hobby
30w=85dB (+10dB)
300w=95dB (+10dB)
600w=98 (+3dB)
1200w=101 (+3dB)
2400w=104 (+3dB)
2800w=105 (+1dB)
It would be weird for a gamer to sit next to a washing machine class sub. One of my many sims as an example of what it takes to get a true sub performance, by the definition in bold for a gamer/workstation sub that can tuck under most desks and still be feet friendly. This was a dual opposed 12" config with around a 650mm x 400mm x 620mm external size cab. Just the right size to not be too far forward to get in the way of the feet and at a good 'putting up the feet to lean back to chill a bit' types of things
The sims were just an exercise to satisfy the curiosity on what it would take for the gamer/workstation to get up there with solid undisputable no grey area and no excuse sub bass
Just reading up on what I can find makes me want to disagree with that. It appears that the reference to 'sub' may be rooted in covering the subsonic band and not the speaker system working below the 'woofer'. Back in the 90's I noticed that systems that used a woofer type unit to create an illusion of low bass but worked higher up out of the sub band and even not really dipping much below 70Hz in the compacts
We all go to the effort of making the distinction between woofer, midrange and tweeter, so we should also make the proper distinction between subwoofer and superwoofer. It does appear that the term 'sub' was used more as a marketing ploy rather than a true description of the device
I wouldn't presume to know the specs of an actual descent commercial cinema but would expect this to be a different type of PA build than what would be found at concerts and raves. I can't imagine it not attempting some sub bass. Even one of the smallest THX systems like my fav z623 can dip its toes into sub bass by apparently comfortably doing 85dB at 40Hz and having the 20dB THX headroom at that point and even providing a useful 30Hz response that does fall short of the THX spec. I suppose that makes this system and PA systems dedicated towards EDM and Edub work in the true subsonic zone but by the same logic sort of makes all those PC systems (even some very expensive ones) use of the word 'sub' as marketing ploy by promoting a false label given to the unit working at the lowish end
Agreed, the band above infa is the sub
We join forums and interact, because we overthink and are just that bit more involved than 'consumer'
Yes, under 16Hz does appear to be referred to as infrasonic when searching online. So 16Hz to around 70Hz must be the true range of operation for a device labelled as a subwoofer. This has to have a good sounding upper response from around 60Hz to 300Hz with variable shelf and cut to blend well with mains
For me personally, buying a large Yamaha HT sub for the newly bachelored pad in 2010 turned out to be a poor experience due to not being able to fill a hole below the small mains. That sub had a variable knob only covering up to 150Hz. That's when I also acquired my first pair of z623 for use as a sub in the bedroom HT system as 4.2 with the satellites from one system on the fore bed height cabinet with a large screen and a sub in either corner beside that cabinet. The other pair of mains went on the wall in the back corners. I went for two Z623s instead of a 5.1 type system due to wanting to route the subs signal to the mains in the receiver's DSP by setting the mains and rears as large, and letting the z623 provide a more seamless blend with its internal filter to avoid the problems encountered with the lounge sub. I prolly was having an early midlife crisis thing so wanted something like that imposing Yamaha there, so the solution to that one was a pair of large Aaron floor standers
I can say so much more about the upper response, but I think that should cover it for now. How about the low-end response? Maybe an F0 of 20Hz dropping to F3 of 16Hz to fade out the infrasonic and keep out of that undesirable effects zone?
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That does reinforce even more that a requirement of a true subwoofer would be to be able to extend to those two lower octaves and do it at with that 20dB headroom above 85dB
As well, the ability to run processing to tune to a domestic situation. Arcade and studio of course would be more engineered to work as a whole
This is becoming my more updated view on a true subwoofer now
A 20Hz F0 with 85dB attained band wide with no higher F3 than 16Hz and with a 20dB reserve headroom to 300Hz can't help but ensure that the music is well covered and most satellite to floor standers well covered. Group delay under 40 above F0, but not sure about phase (what would be a good quality margin here). Some of this is borrowed from THX. And I suppose that rating attained at listening position would determine overall LF system size for the use with the gamers/workstation used as one example of use
My shout, you deserve it. If you ever sail into Hervey Bay, please allow me to host you!
That's also only the acoustic implications re a quality rendition. What about the physical aspects besides ergonomics
Again, researching online through many discussions and such. It seems that a dual opposed type setup just might be a minimum for a 'high' quality 'true subwoofer' to not rattle that gamers desk and PC but to direct the energy to rattle his bones instead!
Again, researching online through many discussions and such. It seems that a dual opposed type setup just might be a minimum for a 'high' quality 'true subwoofer' to not rattle that gamers desk and PC but to direct the energy to rattle his bones instead!
I have never even thought of measuring the SPL numbers that my car sub can put out. Spent the last hour with DJ Joe Fatal Fantasy II CD down at the boat ramp. This is a dance off fave of mine. Is all synth kicks and bass, with the music evolving through the song and over the tracks. Some low sounding stuff came through very solid
Averaged 121 db with absolute peak of 127dB with volume set below audible distortion and on my car receiver, and sub this is 38 on the volume dial. This is just for the subwoofer driver and amp system, though. My fronts can only manage 97db before starting to sound off. I am on my third set of 6.5" woofers in the front doors, having killed the best off JLAudio and Soundstream splits in this location
I need to find a more secluded spot to push the sub as some elderly types folks left their house and came across the street across the park up at Gatetakers Bay ramp. I did the tests in the middle of the empty car park. Also need to find a good test source
This tells me that the idea of 85dB with a 20dB headroom over the subwoofer band is not a bad minimum requirement at all. It does ensure a solid music bass performance as. Having a good further reach in both output and extension can never be a bad thing
Although I do not have any real need for such a device but building one of these minimum requirements should be a real educational experience as well as a reference. Example, I will try to best achieve these numbers in my current projects and compare to this reference to hear and feel actual differences in output
If I am to store such a reference unit under the workstation desk, than I need to shrink it further then 650x400x620mm. I dont think Eric makes a power amp larger than 600w@4R so I need to find another source for the 3kw+ @4R that I am likely to need to nail those 20dB headroom numbers
Again, this is what comes up as a summary to my efforts in finding what are the minimums for a true subwoofer
A 20Hz F0 with 85dB attained band wide with no higher F3 than 16Hz and with a 20dB reserve headroom to 300Hz can't help but ensure that the music is well covered and most satellite to floor standers well covered. Group delay under 40 above F0, but not sure about phase (what would be a good quality margin here). Some of this is borrowed from THX. And I suppose that rating attained at listening position would determine overall LF system size for the use with the gamers/workstation used as one example of use
Averaged 121 db with absolute peak of 127dB with volume set below audible distortion and on my car receiver, and sub this is 38 on the volume dial. This is just for the subwoofer driver and amp system, though. My fronts can only manage 97db before starting to sound off. I am on my third set of 6.5" woofers in the front doors, having killed the best off JLAudio and Soundstream splits in this location
I need to find a more secluded spot to push the sub as some elderly types folks left their house and came across the street across the park up at Gatetakers Bay ramp. I did the tests in the middle of the empty car park. Also need to find a good test source
This tells me that the idea of 85dB with a 20dB headroom over the subwoofer band is not a bad minimum requirement at all. It does ensure a solid music bass performance as. Having a good further reach in both output and extension can never be a bad thing
Although I do not have any real need for such a device but building one of these minimum requirements should be a real educational experience as well as a reference. Example, I will try to best achieve these numbers in my current projects and compare to this reference to hear and feel actual differences in output
If I am to store such a reference unit under the workstation desk, than I need to shrink it further then 650x400x620mm. I dont think Eric makes a power amp larger than 600w@4R so I need to find another source for the 3kw+ @4R that I am likely to need to nail those 20dB headroom numbers
Again, this is what comes up as a summary to my efforts in finding what are the minimums for a true subwoofer
A 20Hz F0 with 85dB attained band wide with no higher F3 than 16Hz and with a 20dB reserve headroom to 300Hz can't help but ensure that the music is well covered and most satellite to floor standers well covered. Group delay under 40 above F0, but not sure about phase (what would be a good quality margin here). Some of this is borrowed from THX. And I suppose that rating attained at listening position would determine overall LF system size for the use with the gamers/workstation used as one example of use
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I get easily distracted. Regardless of higher priority stuff, it has been fun spending a day running sims with a bunch of likely drivers
Easing up slightly on the space constraints makes modelling in subsonic band easier as to be expected but trimming down further also surprisingly worked too
A small true subwoofer built to the minimum requirements is actually fairly easy. It was easier than expected to nail a better than target F3 of 14Hz with F0 at 20Hz and hitting 85dB with 10w and having a 20dB reserve ability. And quite flattering graphs all nailing it. This can be achieved with a single active driver in net 30L
From there it’s fairly easy to scale the size up in 20L increments for an additional driver count or the next driver size up
I’ll make a set of 3 reference virtual true subwoofers with a single driver with the smallest just meeting the spec with 30L and going up almost 40dB headroom in clean output for the largest of around 50L
As well the same drivers in a set of three sizes in dual opposed with the 20L extra volume penalty per unit
Some folks say that such a low end extension is a waste of power. For me personally, it is a waste of space with a 5-string being well covered as plenty
Hence the virtual models. I will build just one from the set of those 6 reference designs for reference and video editing
Now, also will create two bass bin models for two driver sizes. Single driver and optimised for a good low reach of around 30Hz F3. Again pushing the downsizing of cab volumes
Next two more models, these would sit between the ‘true’ and ‘musical’ in terms of extra headroom but using very economical drivers and much lower power 12”s in a single and dual setup. These nail the minimum ‘true sub SOR’
Having these virtual models in WinISD open in the projects pane will be very beneficial for me. At any moment, I would be able to activate a virtual reference and run a quick compare
Sims show that the power to operate these to potential is easily covered by very good value modules from the FFA00x range with four modules for the larger subs
I believe that these minimum requirements are well thought out for a true subsonic bass performance and to avoid typing it all out again, will refer to them as SORSub standing for Statement of requirements for subwoofer
Easing up slightly on the space constraints makes modelling in subsonic band easier as to be expected but trimming down further also surprisingly worked too
A small true subwoofer built to the minimum requirements is actually fairly easy. It was easier than expected to nail a better than target F3 of 14Hz with F0 at 20Hz and hitting 85dB with 10w and having a 20dB reserve ability. And quite flattering graphs all nailing it. This can be achieved with a single active driver in net 30L
From there it’s fairly easy to scale the size up in 20L increments for an additional driver count or the next driver size up
I’ll make a set of 3 reference virtual true subwoofers with a single driver with the smallest just meeting the spec with 30L and going up almost 40dB headroom in clean output for the largest of around 50L
As well the same drivers in a set of three sizes in dual opposed with the 20L extra volume penalty per unit
Some folks say that such a low end extension is a waste of power. For me personally, it is a waste of space with a 5-string being well covered as plenty
Hence the virtual models. I will build just one from the set of those 6 reference designs for reference and video editing
Now, also will create two bass bin models for two driver sizes. Single driver and optimised for a good low reach of around 30Hz F3. Again pushing the downsizing of cab volumes
Next two more models, these would sit between the ‘true’ and ‘musical’ in terms of extra headroom but using very economical drivers and much lower power 12”s in a single and dual setup. These nail the minimum ‘true sub SOR’
Having these virtual models in WinISD open in the projects pane will be very beneficial for me. At any moment, I would be able to activate a virtual reference and run a quick compare
Sims show that the power to operate these to potential is easily covered by very good value modules from the FFA00x range with four modules for the larger subs
I believe that these minimum requirements are well thought out for a true subsonic bass performance and to avoid typing it all out again, will refer to them as SORSub standing for Statement of requirements for subwoofer
Indeed, I noticed higher than 20dB peaks on the kicks in some Sly and Robbie dubs in the waveforms
From the six virtual SORSub models, the smallest being a 10" single driver 30L cab just passes THX levels as described by Dolby Labs and which that I borrowed together with a 16Hz F3
The headroom from 16Hz and up from the reference 85dB flat gets larger with the virtual models starting at 21dB for the smallest and up to 40dB with the dual 12" and higher still for the next one up being the dual 15". These can do better still if modelled in larger cabs but considering that I am deriving the SOR as being domestically acceptable too, cab sizes do need to be reined in to push one direction in sub design
Makes me think that there should be one outright type virtual model too, based around the largest hardware grouping being the dual 15". A max performance no compromise edition would be appropriate too
How is this for headroom? With further headroom or a higher than reference SPL level of 85dB being based upon a 6dB increase per additional cab?
The smallest of the single driver virtual model just barely scrapes in with the SOR. This is based on a 10" driver with 600wrms on each of its two coils. It needs this power to run some Eq on the low end to bring it up flat with the rest. This boost also sees group delay hover just over target and peaking on the boosted part. Which is below 20Hz. Giving it more volume from 5L or more makes for a better response, but already this is beating up the z623 in the subsonic
This would also cost me about $800 AUD to make due to shipping costs for the driver, but as mentioned previously, the dual 12" is more appealing for power lust
Anyway, that's the first reference virtual model. The bare minimum that can hit the SOR from the drivers that I am messing with in that 35L volume. That's quite a large output to place under the computer desk and I don't think that I have across a cab this small that can nail THX at 16-20Hz. While researching this online a few days ago, I came across somewhere that at least two 10s are needed to hit these numbers but the driver seems to just reach half Xmax while producing that 106dB at 20Hz in a very small cab
This would also cost me about $800 AUD to make due to shipping costs for the driver, but as mentioned previously, the dual 12" is more appealing for power lust
Anyway, that's the first reference virtual model. The bare minimum that can hit the SOR from the drivers that I am messing with in that 35L volume. That's quite a large output to place under the computer desk and I don't think that I have across a cab this small that can nail THX at 16-20Hz. While researching this online a few days ago, I came across somewhere that at least two 10s are needed to hit these numbers but the driver seems to just reach half Xmax while producing that 106dB at 20Hz in a very small cab
This is the same driver given 15L more to work with and at full power. High and low pass applied as well as a wide 3dB cut over 100Hz to get flatish. Not too bad
15L more solidly exceeds THX by 3dB all the way down to 16Hz. And this also nails the group delay
Then there is Reference 2 virtual model using two of the same drivers in an 80L volume and at full power
A clean 112dB at 20Hz out 80L. This would be paying too much for shipping. Enough to make it useful for US only. Instead of paying shipping for the locally unavailable driver, that money is better spent on the dual 12" from the virtual models due to costing about the same as the 10" due to being local purchase and even under $1500 AUD for all the BOM. I think I might just make this one to go under the computer desk just so I can have a unit at home that can nail absolute subsonic with high SPL for reference as well as video editing. My daughter is keen on film production too. Will attempt this build after my current trio of speaker projects are done
15L more solidly exceeds THX by 3dB all the way down to 16Hz. And this also nails the group delay
Then there is Reference 2 virtual model using two of the same drivers in an 80L volume and at full power
A clean 112dB at 20Hz out 80L. This would be paying too much for shipping. Enough to make it useful for US only. Instead of paying shipping for the locally unavailable driver, that money is better spent on the dual 12" from the virtual models due to costing about the same as the 10" due to being local purchase and even under $1500 AUD for all the BOM. I think I might just make this one to go under the computer desk just so I can have a unit at home that can nail absolute subsonic with high SPL for reference as well as video editing. My daughter is keen on film production too. Will attempt this build after my current trio of speaker projects are done
@Randy Bassinga : The box modeling programs are giving you the response in "open air". I assume you will listen to the subwoofer inside, and in that case you can expect to obtain room gain from pressurization of the closed space. Room gain is sort of like a boost that rises like a low Q PEQ and at at the lowest frequencies IIRC reaches a slope of 12dB/octave (gain increasing with decreasing frequency). At what frequency room gain starts to kick in depends on the volume of the space, and this is probably why there are wildly varying reports of what is a good subwoofer. In a small room, a small sub can sound amazing...
You seem to be modeling systems that are "flat to 20Hz". That is very likely going to result in overly exaggerated LF in anything but a very large indoor space. Better is a more gradual rolloff starting around 30Hz, e.g. F3 is 30-35Hz and F10 is below 20Hz, e.g. 15 Hz. You seem to be aiming for LF extension and max SPL with a sharper cutoff, and this is not likely to provide accurate and high quality bass response. Also, the "subsonic" response will be weak because it is below the tuning frequency. A sealed sub will provide a better response match to the room gain, and will have more output at infrasonic frequencies e.g. below 20Hz.
My 2 cents...
You seem to be modeling systems that are "flat to 20Hz". That is very likely going to result in overly exaggerated LF in anything but a very large indoor space. Better is a more gradual rolloff starting around 30Hz, e.g. F3 is 30-35Hz and F10 is below 20Hz, e.g. 15 Hz. You seem to be aiming for LF extension and max SPL with a sharper cutoff, and this is not likely to provide accurate and high quality bass response. Also, the "subsonic" response will be weak because it is below the tuning frequency. A sealed sub will provide a better response match to the room gain, and will have more output at infrasonic frequencies e.g. below 20Hz.
My 2 cents...
Hello Charlie and thank you for joining the conversation
Room gain, allow me to mention my personal listening area again. My home sub is louder inside than out. It does have substantial output down to 30Hz. The variable bass boost is set to cut for the indoors listening position but is centred over 50Hz. Yes, room again is real. As are attenuation and tuning options
But I see major problems with the assertion that a roll off around 30Hz is sufficient. Firstly, once you place that in a domestically acceptable box, you are locking your design to that diminishing native output and depending on the room again argument. Take the room away and it falls apart. On my houseboat deck as an example of a HT and entertainment area. Here a compromise device will fail but one built to the SOR will shine. You can drop any frequency to correct for room painlessly
Now keeping with the same, think on this
It is always easier to take something away than it is to add, especially at the extremes of ranges in anything. Imagine that your speaker's build's left panel is 2mm too long. This is an easy trim, isn't it. Now imagine that being 2mm short. Can you imagine what it would take to elegantly add that 2mm back on? Now going back to that 30Hz box. The roll off is too great and if the system is idling at minimal powers, getting DSP to raise that to reach 16Hz is just not going to happen well. The compromise device can make for a great musical system but only dips its toes at the start of the subsonic band. All those DSP boosts and such do is eat up headroom and bring clipping earlier
Secondly. A sealed system does not make for a true subwoofer. But for this assertion to hold true, one must recognise that music was meant to be heard as the recording engineer wanted to present. One must recognise that there is a resonant system providing an effects engine between the recording mixer and the engineers ears. This assertion is based on researching the types of studio monitors present in the industry. These are mostly BR systems for commercially made gear. By playing this recording through sealed speakers, we are creating a presentation that is inaccurate to the engineer's intentions. A true subwoofer will contain that resonant effects as part of the delivery system
Thirdly, a higher roll off like that together with room gain and DSP or Eq to lift subsonic to THX standards will just produce MUD while down tuning from a native flat anechoic or free space response for room correction pays off in greater clarity and realism
Now, please don't take this as an argument. These are just assertions based on studying the industry and the discussions about true subwoofers. This presentation is for a set of virtual true subwoofer models that can be easily made at home as real life units. But the real purpose is as a reference for working with actual projects that are being built. Let's take my HT/miniPA project in the multiway category. Having the reference designs and the project open in WinISD will be a major boon. That project has bass ambitions to well and truly cover a 5-string bass and sacrifice any lower end for portability
At any point, I can activate a reference to check the project's graphs against a known anechoic model to see how a sub on a whale watching tourist boat will play back underwater sounds. The higher roll off boxes depending on room gain for a lift at the top end of the subsonic will fail badly. While an SORSub will eat it all up and laugh. Please note that outright SPL or even higher dynamic range is only a matter of going up to a larger SORSub or increasing their cab count
A compelling dispute against the SORSub concept as bare minimum requirements to be counted as a true subwoofer in terms of subsonic range, note definition as per recording engineer intentions, dynamic range and sheer output is very welcome and invited. A lack of such only reinforces that the surmise is correct and that is a true measure of a device labelled as a subwoofer
Now let's think about that musical config that doesn't need an HT type lower extension and prioritises on portability and clean output. I personally find it easier to aim for goals if I know where the posts are. Again, I feel Lucas Films and Dolby Labs has thought THX very well. The dynamic range/headroom requirements again do seem to make for minimum requirements and the working range extending down to the 5-strings or any synth version of it for EDM type material
Here I would politely bow my noob nose out and hand over the minimum requirements, statement of requirements (SOR) discussions and assertions to guys like Art, @weltersys. The only real input that I could have would start and stop at porch party levels. How about a true Bass Bin and a true Bass Monitor Art?
Here I would politely bow my noob nose out and hand over the minimum requirements, statement of requirements (SOR) discussions and assertions to guys like Art, @weltersys. The only real input that I could have would start and stop at porch party levels. How about a true Bass Bin and a true Bass Monitor Art?
Looks like I am placing these drivers in boxes that are too large and using Eq to build up the 16Hz flat response at the extreme low end. The steep roll off from there is the high pass filter getting rid of the infrasonic
Running sims to the suggested 20Hz flat instead, places the drivers in much smaller cabs and doesn't require any Eq to make up the base reference. That means all that headroom is available for outright SPL gain over the whole LF band
Question, should I revise the goals to 20Hz F3 with 16Hz around F6-10?
Will make for much more smaller boxes too. I am going to run sims for the 15" units too and see if they can do without Eq
Running sims to the suggested 20Hz flat instead, places the drivers in much smaller cabs and doesn't require any Eq to make up the base reference. That means all that headroom is available for outright SPL gain over the whole LF band
Question, should I revise the goals to 20Hz F3 with 16Hz around F6-10?
Will make for much more smaller boxes too. I am going to run sims for the 15" units too and see if they can do without Eq