Here’s something that many people are missing out however; when it comes to speakers that share the same preamp(opposite of the scenario in the video, since those speakers are individually powered), the volume will still be the same at the point of interference. As a result, the 2 speakers will actually have LESS volume than if there were 1; since the preamp is powering the SAME amount of wattage to 2 instead of 1 speaker.
@@INTEGRALPHYSICS Hey thx for the reply! I plan to send a email to Celestion and ask them, since I’ve heard rumors yesterday that they did the experience, where they added the number of speakers but wattage is constant, and that the volume goes up by 3dB despite the same power.
Yes and no... I've tested this with a sound meter. 2 speakers are quieter individually, each speaker produces less decibels than if it were hooked up by itself. However, the two speakers COMBINED produce more decibels than any one speaker wired individually.
I simply played a song and moved the balance left and right and I could feel, without a doubt, that the volume was much louder with 2 speakers and even the bass was much more powerful. I felt that the volume doubled or even more than with just one speaker playing.
Well this is misleading. If you go from 1 speaker to 2 speakers you get a 6 dB increase in volume (provided they are near each other (1/4 wavelength spacing)). What you forgot to include is that when you double your cone area (2 drivers vs 1 driver) you double the efficiency of the cone movement into sound of both speakers. Each speaker on the example on the right will now output 53 dB's which will then together sum to 56 dB's. +3 dB's for doubling the power but also +3 dB's for doubling the efficiency of the system (ie: your high impedance (cone) into low impedance (air) is a lossy endeavour, anywhere from 0.1 to 10% efficient depending on the driver/enclosure combo. Increasing the cone area increases the efficiency of the system. Using a paddle is a more efficient way to paddle a canoe then a broom stick even though the same energy is used). That extra +3 dB's from doubling the cone area doesn't go on forever, with subwoofers for example it will top out somewhere around 30% efficiency. So you would gain +6 dB's for every doubling of sub cabinets and then that would level off and you would only get the +3dB's per doubling after that. That occurs somewhere around 12 double 18's subs (pro audio industry standard sub cabinet). That +3 dB's eventually has a limit as well as air gets non linear with high spl's and the fact that you can't actually put that many cabinets close enough to the measurement location (additional subs will be much farther away due to the damn Pauli Exclusion Principle.)
Nice explanation. I was a bit confused as to how a doubling of the amplitude of the sound waves gave a 6 dB increase in volume while the power increase seemed to imply only a 3 dB increase. As you say, if the phases line up, we can consider the drivers coupled and the efficiency of the system goes up which explains the extra 3 dB. I assume it works better for low frequencies which is why you focus on subwoofers in your explanation. I also assume this can be modeled with circuit analysis where the impedance matching determines where the power goes.
@@mesterha Yes, lower frequencies is where you are going to see the biggest improvement in efficiency gain as the wavelength to driver size is massive so efficiencies start off low. High frequencies, especially horn loaded compression drivers are already near their maximum efficiency. Also, it is hard to get high frequency drivers close enough together to couple without causing an interference pattern (comb filtering) as the wavelengths are smaller then most drivers themselves. It requires some creative engineering in building unique waveguides so they can couple. The only company I can think of that does that successfully would be Danley sound labs.
Two main sources of sound ideally from the same distance and directly at your ears will always sound louder and more “full” than one speaker centered in front of you. I don’t know the physics behind it, but it’s immediately observable to anyone.
I just bought a Bose s1 pro $200 off on Amazon. My question is will I notice a significant difference if I added another one. I could daisy chain them or use the bose app to sync them. If not at least the pair would be in stereo if I use app. Ultimately I was just looking to increase volume. I think I will just stick with the single one if it doesn't increase the volume significantly. Thanks in advance!!!
i though perceive loudness as twice is 3 db increase? so basically you are experiencing twice the loudness? correct me If i’m wrong I am only new to this
@INTEGRALPHYSICS I know this is a late reply but would it need to double for each time? Like, would 4 speakers net another 3 DB followed by 8 being another 3 DB? Or is it dimishing on a higher scale? In my example and assuming you could somehow fit that many speakers in one space, 8 speakers all playing at 50 DB would end up at 59 DB. 16 would be 62 DB and so on.
This video answers that question as well. Each speaker adds 3db everything else being equal. You'd need 50/3 or about 17 speakers to increase spl from 50db to 100db. That is assuming that the wattage to each speaker remains the same.
@@saxappeal74 that is incorrect. each speaker does NOT add 3db. only the second added speaker adds 3db. every speaker afterwards will come out to less than 3 additional db.
Thanks. I was looking at using one large traditional generator that was rated at 73 decibels or using two smaller inverter generators rated at 58 decibels. With this, I found the two smaller generators combine to 61.01 decibels. I know which I'm using now lol.
that's not how sound goes, it is not like a boring mathematic because sound can vary depend of space and obstacles. What kind of ported or baffles/Box they are mounted and One speaker can be more powerful than two speakers depend on brand because different brand of speakers give different loudness in terms of its wattage and producing noise like for example, a JBL woofer with 250 watts can be more powerful than a non branded 600watt woofer
Don't confuse electrical power drawn with the sound power produced. Most speakers cant even produce 1Watt of sound. Once you get into sound power produced, then yes, it reduces down to boring math equations, no way around it.
Yes double the power is double the power, however your ear does not work on a linear scale. A typical conversation is about 100x less sound power than a truck driving down a road... but you don't hear it as being 100x louder.
3db is not double the sound. 3db is double the power required to play such sound which is actually proven in this video (2 speakers is double of 1 speaker). double the sound requires a 10db increase
Exactly! He now has double the cone area so the impedance loss from cone into air halves. This is what happens when a mathematician pretends he's an engineer.
I was once very good at math however with lack of practice I'm not as sharp as I used to be with that being said I wish you would have showed your work....🤦🏽♂️🤷🏽♂️
I have an easy time teaching this stuff in class because its my job to be aware of what people already know (both math and physics). I have found making youtube videos quite hard because I never know exactly what my audience comes to me with and how far they want to me to take the problem. Thank you for the feedback. On a more tangible note, I'm guessing you're reffering to the jump between the 2nd to last line and the 53dB... I just dumped that into a calculator, theres no way I could do that without one. The other potential place of confusion is how 10^5 turned into 10^-7. I multiplied each side by 10^-12 there. Again, sorry for skipping the algebra.
Contradictory experiment...the moment you a second speaker adds a 3db, what do you call that?...just go plactical you'll provw your self that 2speaker are louder than 1 speaker even if from the same power source...1 watt plus 1 watt that 2watts😂....
Here’s something that many people are missing out however; when it comes to speakers that share the same preamp(opposite of the scenario in the video, since those speakers are individually powered), the volume will still be the same at the point of interference. As a result, the 2 speakers will actually have LESS volume than if there were 1; since the preamp is powering the SAME amount of wattage to 2 instead of 1 speaker.
Constant power should THEORETICALLY produce the same volume in dB... However I don't doubt that in reality speakers work exactly as you describe.
@@INTEGRALPHYSICS Hey thx for the reply! I plan to send a email to Celestion and ask them, since I’ve heard rumors yesterday that they did the experience, where they added the number of speakers but wattage is constant, and that the volume goes up by 3dB despite the same power.
Post up their findings.
Yes and no... I've tested this with a sound meter. 2 speakers are quieter individually, each speaker produces less decibels than if it were hooked up by itself. However, the two speakers COMBINED produce more decibels than any one speaker wired individually.
I simply played a song and moved the balance left and right and I could feel, without a doubt, that the volume was much louder with 2 speakers and even the bass was much more powerful. I felt that the volume doubled or even more than with just one speaker playing.
Take out your phone, open up a decibel-meter app and repeat the experiment.
Maybe it's not louder, but the sound feels more open, more real due to stereo sound. It feels like it fills the room more, but not louder.
Well this is misleading. If you go from 1 speaker to 2 speakers you get a 6 dB increase in volume (provided they are near each other (1/4 wavelength spacing)). What you forgot to include is that when you double your cone area (2 drivers vs 1 driver) you double the efficiency of the cone movement into sound of both speakers. Each speaker on the example on the right will now output 53 dB's which will then together sum to 56 dB's. +3 dB's for doubling the power but also +3 dB's for doubling the efficiency of the system (ie: your high impedance (cone) into low impedance (air) is a lossy endeavour, anywhere from 0.1 to 10% efficient depending on the driver/enclosure combo. Increasing the cone area increases the efficiency of the system. Using a paddle is a more efficient way to paddle a canoe then a broom stick even though the same energy is used). That extra +3 dB's from doubling the cone area doesn't go on forever, with subwoofers for example it will top out somewhere around 30% efficiency. So you would gain +6 dB's for every doubling of sub cabinets and then that would level off and you would only get the +3dB's per doubling after that. That occurs somewhere around 12 double 18's subs (pro audio industry standard sub cabinet). That +3 dB's eventually has a limit as well as air gets non linear with high spl's and the fact that you can't actually put that many cabinets close enough to the measurement location (additional subs will be much farther away due to the damn Pauli Exclusion Principle.)
Nice explanation. I was a bit confused as to how a doubling of the amplitude of the sound waves gave a 6 dB increase in volume while the power increase seemed to imply only a 3 dB increase. As you say, if the phases line up, we can consider the drivers coupled and the efficiency of the system goes up which explains the extra 3 dB. I assume it works better for low frequencies which is why you focus on subwoofers in your explanation. I also assume this can be modeled with circuit analysis where the impedance matching determines where the power goes.
@@mesterha Yes, lower frequencies is where you are going to see the biggest improvement in efficiency gain as the wavelength to driver size is massive so efficiencies start off low. High frequencies, especially horn loaded compression drivers are already near their maximum efficiency. Also, it is hard to get high frequency drivers close enough together to couple without causing an interference pattern (comb filtering) as the wavelengths are smaller then most drivers themselves. It requires some creative engineering in building unique waveguides so they can couple. The only company I can think of that does that successfully would be Danley sound labs.
Two main sources of sound ideally from the same distance and directly at your ears will always sound louder and more “full” than one speaker centered in front of you. I don’t know the physics behind it, but it’s immediately observable to anyone.
I just bought a Bose s1 pro $200 off on Amazon. My question is will I notice a significant difference if I added another one. I could daisy chain them or use the bose app to sync them. If not at least the pair would be in stereo if I use app. Ultimately I was just looking to increase volume. I think I will just stick with the single one if it doesn't increase the volume significantly. Thanks in advance!!!
More volume requires more money... no way around that.
Helpful. Thank you 😊
Glad it was helpful!
i though perceive loudness as twice is 3 db increase?
so basically you are experiencing twice the loudness?
correct me If i’m wrong I am only new to this
3dB increase corresponds to twice the energy/power not double the perceived sound.
it requires twice the energy to make something 3 db louder. perceived loudness is every 10 db increase.
@INTEGRALPHYSICS I know this is a late reply but would it need to double for each time? Like, would 4 speakers net another 3 DB followed by 8 being another 3 DB? Or is it dimishing on a higher scale? In my example and assuming you could somehow fit that many speakers in one space, 8 speakers all playing at 50 DB would end up at 59 DB. 16 would be 62 DB and so on.
This video answers part of my question but really I want to know, if one speaker is 50db how many speakers would make a sound 100db?
This video answers that question as well. Each speaker adds 3db everything else being equal. You'd need 50/3 or about 17 speakers to increase spl from 50db to 100db. That is assuming that the wattage to each speaker remains the same.
@@saxappeal74The video doesn’t say this. If you plug in the same numbers, you’ll see 17 speakers comes out to about 62 dB.
The answer is 100,000.
@@af57162 You couldn't stack 100,000 speakers close enough together to do that.
@@wally7856 this does not change my point
@@saxappeal74 that is incorrect. each speaker does NOT add 3db. only the second added speaker adds 3db. every speaker afterwards will come out to less than 3 additional db.
Cool presentation. I like how you used pen and paper 👍
Thank you! Cheers!
So how do you make them double the dp ? That basically means I’m wasting my time wiring 2 speakers when I can just wire 1 cause 2 makes no difference?
Thanks. I was looking at using one large traditional generator that was rated at 73 decibels or using two smaller inverter generators rated at 58 decibels. With this, I found the two smaller generators combine to 61.01 decibels. I know which I'm using now lol.
Fantastic video, thank you!
that's not how sound goes, it is not like a boring mathematic because sound can vary depend of space and obstacles. What kind of ported or baffles/Box they are mounted and One speaker can be more powerful than two speakers depend on brand because different brand of speakers give different loudness in terms of its wattage and producing noise like for example, a JBL woofer with 250 watts can be more powerful than a non branded 600watt woofer
Don't confuse electrical power drawn with the sound power produced. Most speakers cant even produce 1Watt of sound.
Once you get into sound power produced, then yes, it reduces down to boring math equations, no way around it.
0:21 you say run them at the same power the pair has to be 2x power to work
The dB is a Measure of power gain 3dB increase is always x2 power 😊
What do you mean "not much louder"? 3Db actually is double the sound. It is twice as loud to have 2 speakers... exactly as expected.
Yes double the power is double the power, however your ear does not work on a linear scale. A typical conversation is about 100x less sound power than a truck driving down a road... but you don't hear it as being 100x louder.
I apologize for my ignorance but I am scratching my head
3db is not double the sound. 3db is double the power required to play such sound which is actually proven in this video (2 speakers is double of 1 speaker). double the sound requires a 10db increase
You did not take account the acoustical gain of two speaker together. The increase is 6 db not 3 db.
Exactly! He now has double the cone area so the impedance loss from cone into air halves. This is what happens when a mathematician pretends he's an engineer.
I was once very good at math however with lack of practice I'm not as sharp as I used to be with that being said I wish you would have showed your work....🤦🏽♂️🤷🏽♂️
I have an easy time teaching this stuff in class because its my job to be aware of what people already know (both math and physics). I have found making youtube videos quite hard because I never know exactly what my audience comes to me with and how far they want to me to take the problem. Thank you for the feedback.
On a more tangible note, I'm guessing you're reffering to the jump between the 2nd to last line and the 53dB... I just dumped that into a calculator, theres no way I could do that without one.
The other potential place of confusion is how 10^5 turned into 10^-7. I multiplied each side by 10^-12 there. Again, sorry for skipping the algebra.
Contradictory experiment...the moment you a second speaker adds a 3db, what do you call that?...just go plactical you'll provw your self that 2speaker are louder than 1 speaker even if from the same power source...1 watt plus 1 watt that 2watts😂....
But wait. Every 3db gain is equivalent to doubling the volume so it actually does make sense. 😊
3dB gain is 2x the power, 6dB gain is 2x the voltage and 7-10dB gain is 2x the perceived loudness to the human ear.