Thats not headroom then is it. Greensleeves samplers is a raggae mix tape? Heavy bass? So whats so special about it? You don;t have your head, wrapped around, headroom.
Yeah, I just posted several examples above, using what you call PA drivers... and your experience between the hi-fi and PA systems is likely, headroom.
No you don't you just proved you don't yet understand what it is. You went into a hi-fi shop and demo'd systems that lacked headroom.... then you moved on to PA were were high headroom is more common and you stated;
Jl W7 have some of the highest Xmax in a woofer I've ever seen... Thats an increase in Headroom again.... You are confused. Headroom is what allows you play louder and clean at the same time... You just stated that you don't need to be able to play a louder system at low volume, you just need massive dynamic headroom.... They are both the same thing... and you are very confused.
Randy Bassinga, thats true, many small speakers just can't play very loud. It takes quite formidable system to approach "realistic levels", many people can sing louder than their loudspeakers can. On the otherhand a mobile phone internal loudspeaker can appear quite loud, it has about no bass and is very distorted, it still appears loud. Perhaps people are satisfied with small systems as they seem loud enough (too loud as they sound bad), until hearing a big enough that can actually reproduce lows, and cleanly, which drops jaw on the floor usually 😀
If individual favorite SPL target is unknown, it would be safe to have a system that is capable of levels that most recorded material was likely mixed and mastered. Which is likely standardized many times, and probably has to do with hearing system linearity and long term exposure limits and stuff like that, a comfortable loud listening level, beyond which it gets bit uncomfortable and perhaps unnecessarily loud for home hifi.
Here is one standard that defines reference listening level https://tech.ebu.ch/docs/tech/tech3343-v2.pdf
Forgetting room gain and all that kind of stuff, taking the 82db number from the standard, adding the 18db headroom we'd need speakers with 100db of clean SPL capability to form a system could be fine. But, if one accounts for some room effects and preference curves and all that, perhaps some extra is required? Anyway, lets simplify to get some ballpark reference.
Lets look at volume displacement to SPL chart, which indicates achieving 100db at 30Hz with a closed box requires roughly 300cm3 volume displacement. This would be single 6.5" woofer with 150cm2 cone area making 2cm of p-p excursion, perhaps some modern driver could do it clean, ported box and all that. On the other hand, a 15" woofer with about 850cm2 cone area would need only about 3mm of p-p excursion to achieve the same.
This simple calculation indicates that a speaker system with 6" woofer, that is capable of some nice bass, is likely top shelf stuff and costs a lot. It might be better to get speakers with multiple 6" drivers, or preferably even more and bigger to get some headroom over minimum requirement, account for not so ideal drivers and so on. For reference, single 12" equals almost four 6" woofers in cone area, 15" equals almost 6.
ps. it's fun to read datasheets that could read "85db sensitivity 1W / 1m at 1kHz" and then realize the woofer actually can't play that loud on the lows without sounding bad 😀
If individual favorite SPL target is unknown, it would be safe to have a system that is capable of levels that most recorded material was likely mixed and mastered. Which is likely standardized many times, and probably has to do with hearing system linearity and long term exposure limits and stuff like that, a comfortable loud listening level, beyond which it gets bit uncomfortable and perhaps unnecessarily loud for home hifi.
Here is one standard that defines reference listening level https://tech.ebu.ch/docs/tech/tech3343-v2.pdf
Forgetting room gain and all that kind of stuff, taking the 82db number from the standard, adding the 18db headroom we'd need speakers with 100db of clean SPL capability to form a system could be fine. But, if one accounts for some room effects and preference curves and all that, perhaps some extra is required? Anyway, lets simplify to get some ballpark reference.
Lets look at volume displacement to SPL chart, which indicates achieving 100db at 30Hz with a closed box requires roughly 300cm3 volume displacement. This would be single 6.5" woofer with 150cm2 cone area making 2cm of p-p excursion, perhaps some modern driver could do it clean, ported box and all that. On the other hand, a 15" woofer with about 850cm2 cone area would need only about 3mm of p-p excursion to achieve the same.
This simple calculation indicates that a speaker system with 6" woofer, that is capable of some nice bass, is likely top shelf stuff and costs a lot. It might be better to get speakers with multiple 6" drivers, or preferably even more and bigger to get some headroom over minimum requirement, account for not so ideal drivers and so on. For reference, single 12" equals almost four 6" woofers in cone area, 15" equals almost 6.
ps. it's fun to read datasheets that could read "85db sensitivity 1W / 1m at 1kHz" and then realize the woofer actually can't play that loud on the lows without sounding bad 😀
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If the system is already drawing on massive reserves to play the peaks while playing at volume that you can still talk to someone sitting across from you. All that reserve is the headroom. It doesn't mean that you can actually play cleanly at those louder levels too. Where will the reserve come from then?
You appear to be saying to build to a clean 120db to be clean at 90db, I am asking what level do you build clean to, to play clean at 120db so that you may play clean at 90db. Get it? Where does it end?
Might be more appropriate to say build to a solid, comfortable level and have enough bandwidth for that level
You appear to be saying to build to a clean 120db to be clean at 90db, I am asking what level do you build clean to, to play clean at 120db so that you may play clean at 90db. Get it? Where does it end?
Might be more appropriate to say build to a solid, comfortable level and have enough bandwidth for that level
Correct, that is what you call headroom or dynamic range.
20 db of headroom is not a uncommon desire.
What is desirable or necessary depends on the source and source material.
A lot of the digital media today, on Spotify or other popular digital sources is often squished rather flat.
And after that you repeat the calculation for the actual listening distance as desired 😉.
First start with, Desired max listening average, Then account for distance using a spl/distance calculator
https://www.omnicalculator.com/physics/distance-attenuation
Then add another 20-15db for Transients. Done....
You tell yourself how much you want/need
The tricky part is saying, you've arrived. As you seen TNT poked fun at me about not building a "120db capable system". Hes stuck on measurements I've shown even though I have the biggest tweeter ever and science agrees there's no correlation between THD and perception. He's never heard my system or one like mine, but I am listening to it for sure, and my ears are not amateur. I can turn my system to the point of "too loud" and hear no problems. Not only is my too loud way louder than most of these guys too loud, my ears are trained.... I'd only expect similar from other sound engineers in the group. The majority of people here are not listening to Reggae or anything remotely as bass heavy. You got lucky and found me. I produce and listen to Rap, I am very familiar with Raggae even have some Rasta Uncles 🤣 Me not scared of your bass mon, me got 4,18" woofas and plan to get 4 more lol. What I think you should understand is that the people who have told you they have the "Hi-Fi" lied to you....You won't find their speakers at the Doby/Imax/THX Theater. The system there is not afraid of Raggae or an explosion that hits very loud at some low frequency but the fidelity, is definitely, there... Now the theater does have the Room acoustic to compliment but the same scientific approach is applied there as well, in regards to headroom.
Theres no replacement for displacement - Big Drivers, big Horns/Waveguides, big Enclosures, for big efficiency.
Reggae has some pretty serious bass lines, depending on your desired output, looking at your LF portion of the system, you might want 4 - 18"s that are sealed, or 2 18's that are a 4th order design you might want stereo subs or 4 cornered subs, etc, theres lots of paths. You might do a tapped horn, I dunno, but the idea is, this can be broken down to a science, because thats exactly what it is, Acoustics. After you've studied for a while you will have your own recipe to get what you want but I promise you will operate under the same physics as everyone else here one earth.
I can tell you my recipe but the next person will laugh. Get all or the majority of your output down to or under ~2mm lol at transient peak level. Sue me.
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Not possible in my case, but has a positive that it saves me from massive boxes, I am starting to consider wall hanging flat cabs, so I may use larger drivers
With the headroom thing. I am prolly thinking along the lines of why buy a corvette to drive 110kmph. Just get a Holden with the same engine and idle along at 110 and enjoy the legroom and view
Brand Names/Car Makes, do not imply a certain horsepower. No one is suggesting a certain brand, I am suggesting a v12 for hauling purposes, no reason to use a too small motor that will obviously be highly strained and over heat. Big woofer is the V12, little woofer is the v4... This analogy falls apart as soon as you try to talk about turbos and super chargers and advanced configurations of cam-less motors... That stuff doesn't exist in the speaker world except, a horn might be a turbo/supercharger.... anyway, your analogy but translated might be
"I am prolly thinking along the lines of why buy a Focal or Insert Fancy Brand name here to play 115db/1m. Just get a Common Name Brand? with the same performance (115db/1m) and enjoy the money saved and high sound quality...."
Notice how nothing said referred to a motor specifics. I don't care about the cars name I just want to know what type of motor gives that performance and why... Well, we were just conversing that very topic but I can tell that you will end up with more questions. The last 4-5 pages or so I just got my butt chewed about what really matters about woofer performance. le and the impedance curve is important. Bl to mass ratio is on my list, as well as a low Qes but we didn't talk about Xmax and Sd because everyone already knows - there's no replacement for displacement.. the JL audio subwoofer you spoke up has very larger Xmax, some 34mm of it... that is impressive and much quality bass is known from that woofer. Once you know the science of it, its no longer a mystery. JL is a brand, Xmax is spec that is important in bas production... I care about Xmax and Sd for example and not so much about JL audio. Jl audio is operating under the same physics as every other brand.
At least in this thread, we are discussing High efficiency systems, with a focus on 2ways or the similar option of 2 acoustical axi's.
"I am prolly thinking along the lines of why buy a Focal or Insert Fancy Brand name here to play 115db/1m. Just get a Common Name Brand? with the same performance (115db/1m) and enjoy the money saved and high sound quality...."
Notice how nothing said referred to a motor specifics. I don't care about the cars name I just want to know what type of motor gives that performance and why... Well, we were just conversing that very topic but I can tell that you will end up with more questions. The last 4-5 pages or so I just got my butt chewed about what really matters about woofer performance. le and the impedance curve is important. Bl to mass ratio is on my list, as well as a low Qes but we didn't talk about Xmax and Sd because everyone already knows - there's no replacement for displacement.. the JL audio subwoofer you spoke up has very larger Xmax, some 34mm of it... that is impressive and much quality bass is known from that woofer. Once you know the science of it, its no longer a mystery. JL is a brand, Xmax is spec that is important in bas production... I care about Xmax and Sd for example and not so much about JL audio. Jl audio is operating under the same physics as every other brand.
At least in this thread, we are discussing High efficiency systems, with a focus on 2ways or the similar option of 2 acoustical axi's.
I thought everyone know about the 4 door family car with the corvette engine in it 😕
Oh well, I suppose a JL with an FR driver in one box is technically a high space efficiency system two-way but excluded from this party as I suppose its many pages are about power efficiency. .....Actually, trying some others like CT Sounds and DS18 too. All are the long xmax kind. My old W7 is dead, and they cost too much
I don't claim to know the science of it but do enjoy good sounds and shy away from too much shrill treble and mid-content as well as bass that just strums along. Are there folks discussing tiny but hugely potent systems anywhere? Some of us are too lazy to clean a big house or build a big speaker....built too many boats and things and rebelling from big builds and things
Oh well, I suppose a JL with an FR driver in one box is technically a high space efficiency system two-way but excluded from this party as I suppose its many pages are about power efficiency. .....Actually, trying some others like CT Sounds and DS18 too. All are the long xmax kind. My old W7 is dead, and they cost too much
I don't claim to know the science of it but do enjoy good sounds and shy away from too much shrill treble and mid-content as well as bass that just strums along. Are there folks discussing tiny but hugely potent systems anywhere? Some of us are too lazy to clean a big house or build a big speaker....built too many boats and things and rebelling from big builds and things
I would suppose that if you are discussing a two way the people in this thread are still interested. Like if you were trying to figure out how to achieve the thread title but have size constraints, the idea would be ok, whats the biggest size you can afford to deal with and then move from there.
I would start like I described already
but be conscious that
"Hofmann's Iron Law; three parameters that cannot all be had at the same time. They are low-bass reproduction, small (enclosure) size, and high (output) sensitivity." Hofmann stated that designers could pick two of these three parameters, but in doing so, it would compromise the third parameter."
Physics dictates this, its not an opinion. the small cabinet will suffer LF sensitivity. So for example the small cabinets using the JL audio W series woofer, will be supplied with massive amounts of power to reach these goals. This guy below is or was using W series Jl subs and using something like 1500watts? The sensitivity is about 4db lower than one of my subs at 30-20hz. I have a 18" with 14mm of xmax... the Jl audio 13" puts out slightly more bass 2-3db more from 30hz-20hz.... So it can output as much bass as an 18" woofer (thanks to the huge xmax). Give an 18" 34mm xmax and the Jl is now surpassed.
Im not sure you are interested in a 2 way are you? I mean if you are considering the sub section separate. 50hz and above can potentially be done small enough. You are looking at something like this with 230liter sealed box from a Jl w13" with about 1200 watts.
Just don't forget you are sacrificing performance for size and trying to compensate with power. It can work but just not as good? The above if ported, it will output more but at the cost of some SQ points.... depending on who you ask... and then you'd need something similar in size for the main cabinet is my guess? So about 400 liters per side, if going for high spl with coverage into the sub territory?
Well just like us, Manufactures know that to put big output in a tiny box is "desirable" and to charge a premium for anything worthy of the task. The Jl audio sub is comparable to a sub that's 18" with 14mm xmax... and neither are cheap. To go cheap you have to go big to get the same performance.
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Understood, trying to make a very small 20hz soundbar for a small houseboat that we are making for retirement. A tiny 40hz sub for my smoking and typing (should be working on the bass amps) area 😀 . Both are under discussion in subwoofers
If the 40hz sub works out. I'll make a quartet of tiny cabs with that driver and a potent 3.5" FR in each for some wine pon meh on the deck 🙂
The bad jaycar amp died and killed the W7
Not trying to make Fathoms, maybe tiny versions for the houseboat in a soundbar format with this in a 35L with two PR as wall hanger bar with 1kwrms
https://ds18.com/cdn/shop/files/ZXI...0-9a88-8fe34d12869a.pdf?v=9591678357036594353
And this in a tiny 40hz box for music. I have some other drivers to compare too. If it works, Then will put make four more featuring a smaller chamber for integrating a powerful 3.5" FR or two in a common cab. Four cabs spread around a 5m x 3m open deck and fitted to canopy beams
https://ds18.com/cdn/shop/files/ZR6...-bf3e-d51fd6dfafb1.pdf?v=11627584538227543164
I would look at movie THX SPL levels as a reference. They are "safe" and don't get stupid loud WRT hearing damage. My DIY HT mains use higher sensitivity Pro drivers that are designed max out at 115dB peak clean. They are "under powered" WRT the individual driver power handling by design to limit SPL. At any reasonable listening level say 85-90 dB average they are effortless and all components including amps are not stressed. Sensitivity is 98dB @ 1 meter.
Rob 🙂
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I am replicating one that's already proven awesome for a small open area, even though it was designed for gaming. Trying to do a more capable version using more powerful amps and drivers but in one common cab with sub compartments. Only thing I can't figure out is how to replicate the embedded DSP based compressor/limiter on each channel
What happened to the bring it on bit? Do you keep editing? Anyway, try this. Turn it up until Sly is kicking you in the chest and separate the bass notes from the kick at the rim shots....its awesome when pulling up alongside a doofdoof or metalhead 😀
I would agree with this while also adding that beyond 120 dB one is in dangerous territory as damage can happen very quickly. That said, I have measured 120 dB(A) at movie theaters and concerts (even acoustical ones) on several occasions, but mostly short duration peaks. Still, if one wants realistic levels in a HT for film or concert recordings, then you have to be able to produce 120 dB cleanly.
For bass however this is not actually true. We tend to feel high SPL bass more than hear it and in concerts LFs often exceed 120 dB - which is not that dangerous as long as its LF. However, any time your ears ring after a concert, damage has been done (been there done that!)
It is almost always the bass that limits realistic volumes like these as it takes a large amount of driver area to accomplish this and most people just aren't willing to give the LF this much resources.
You may have already said it in the past, but if you can state how you personally consider yourself to have arrived at this point in performance, that'd be great. I know that you don't use Thd. Do you model/design to reach a certain excursion at peak, or do you just use your ears?