I like F1. I recall the battles at McLaren between Lewis Hamilton and Jenson Button. The difference between the drivers (excuse the pun) is that Button needed a perfect set-up to perform but Hamilton could achieve good results, wringing performance out of a less than ideal set-up by driving it like he stole it.
This scenario leads me to question the data that the 'Airfix posse' base their decisions on. We are informed that the Acme 12x Turbo is a world-beater but requires 90 litres to fully flex its muscles. Subscribers will discard the option based on the volume requirement. But there is no data informing the customer a 50% reduction in cabinet volume decreases performance by only 3% - still ahead of the competition.
Maybe my observations are both subjective and anecdotal but I've experienced drivers that will do their job to the best of their ability in the environment provided and other, prima donas who will down tools if their every desire is not met.
This scenario leads me to question the data that the 'Airfix posse' base their decisions on. We are informed that the Acme 12x Turbo is a world-beater but requires 90 litres to fully flex its muscles. Subscribers will discard the option based on the volume requirement. But there is no data informing the customer a 50% reduction in cabinet volume decreases performance by only 3% - still ahead of the competition.
Maybe my observations are both subjective and anecdotal but I've experienced drivers that will do their job to the best of their ability in the environment provided and other, prima donas who will down tools if their every desire is not met.
Wow, you want advice based upon experience, yet your first point is to slur a percentage of those. Based upon your displayed experience and knowledge, you're not really in a position to do so.
This smells like a strawman. Please give examples that back up you proposition and define what 3% decrease in performance means in technical terms.
Trying to work out how I can drive a subwoofer like I stole it...😕(keep turning it up until it goes pop ?)😀
When a member of the 'Airfix posse' models the Acme 12x Turbo they can adjust the box volume in their choice of modelling program and see what a 50% reduction in box volume does. They can also model the port to make sure it's not being overloaded.
The one thing about your posts I find a little strange is that none of the 'subwoofer' drivers you are using are actually subwoofers. Most are 6" / 8" drivers in cheap plastic enclosures. You recently mentioned tuning to 50Hz. That's midbass territory.
Maybe treat yourself to a pair of decent 12's , build the 'airfix posse prima donna' oversize boxes for them (out of plywood instead of plastic) and drive them like you stole them. It might surprise you 😀
Edit: Maybe I'm being a little sarky, but basically when modelling we can choose box size , driver, tuning frequency, EQ, power requirements, etc. If I want a 50 Litre enclosure I can model various drivers to find the best fit. If I want the best driver for my 10 watt amp I can model various drivers to find the best fit.
What modelling programs do is allow you to work out the best solution for your own individual situation. Please do not fall into the camp that thinks that modelling programs tell you what to do.... You tell the modelling program what to do and make decisions based on on the programs results.
When a member of the 'Airfix posse' models the Acme 12x Turbo they can adjust the box volume in their choice of modelling program and see what a 50% reduction in box volume does. They can also model the port to make sure it's not being overloaded.
The one thing about your posts I find a little strange is that none of the 'subwoofer' drivers you are using are actually subwoofers. Most are 6" / 8" drivers in cheap plastic enclosures. You recently mentioned tuning to 50Hz. That's midbass territory.
Maybe treat yourself to a pair of decent 12's , build the 'airfix posse prima donna' oversize boxes for them (out of plywood instead of plastic) and drive them like you stole them. It might surprise you 😀
Edit: Maybe I'm being a little sarky, but basically when modelling we can choose box size , driver, tuning frequency, EQ, power requirements, etc. If I want a 50 Litre enclosure I can model various drivers to find the best fit. If I want the best driver for my 10 watt amp I can model various drivers to find the best fit.
What modelling programs do is allow you to work out the best solution for your own individual situation. Please do not fall into the camp that thinks that modelling programs tell you what to do.... You tell the modelling program what to do and make decisions based on on the programs results.
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I won't answer your spurious comments designed to defend your tenuous position. However, I can establish that manufacturer's data is wildly inaccurate. Subsequently, any calculations based on this data are invalid.
Subwoofers make no sound in spreadsheets. There are incalculable real world variables which invalidate modelling data. My ears tell me there's about a 3dB difference at 50Hz between me sitting on my sofa and lying on my sofa.
In practical terms there is no finesse to the domestic subwoofer. There not much 'musical' below about 35Hz. And any decent full range speakers are good down to about 55Hz. This leaves the subwoofer to be responsible for a very narrow frequency range. It's a just a grunt, any texture to a bass sounds is dictated by the overtones, frequencies handled by the woofers.
The reason I refer to modellers as the 'Airfix Posse' is a response to a previous conversation about drivers of different specifications sharing the same airspace. Because the popular modelling software could not accommodate the scenario the overall consensus is that it should not / cannot be done.
The evidence that others (including Sony) had manufactured such speakers killed the debate.
I admit I'm no expert in the dynamic behaviour of loudspeaker drivers, what facilities a driver needs under what circumstances - I have no idea.
There can be no scientific advances without innovation.
You like 'big stuff', so consider a 12" Subwoofer and a 12" Woofer in the same 100 litre cabinet. The subwoofer requires 80 litres for best performance and the woofer requires 50 litres. The bass guitarist strikes an 'E', the woofer tells the sub: "take whatever displacement you need, I can handle all the overtones and stuff in 20 litres". An Oboe strikes up. "Nothing for me do here," says the sub. "You can have the entire 100 litres to yourself."
If you can follow this logic: you now have a cabinet that is ultra-efficient at reduced power but disappoints under full load.
We can return the motorsport analogy and discuss how VVT became a thing but - innovation.
Please not respond to post without reviewing this link: SONY SS-S3 - YouTube
Subwoofers make no sound in spreadsheets. There are incalculable real world variables which invalidate modelling data. My ears tell me there's about a 3dB difference at 50Hz between me sitting on my sofa and lying on my sofa.
In practical terms there is no finesse to the domestic subwoofer. There not much 'musical' below about 35Hz. And any decent full range speakers are good down to about 55Hz. This leaves the subwoofer to be responsible for a very narrow frequency range. It's a just a grunt, any texture to a bass sounds is dictated by the overtones, frequencies handled by the woofers.
The reason I refer to modellers as the 'Airfix Posse' is a response to a previous conversation about drivers of different specifications sharing the same airspace. Because the popular modelling software could not accommodate the scenario the overall consensus is that it should not / cannot be done.
The evidence that others (including Sony) had manufactured such speakers killed the debate.
I admit I'm no expert in the dynamic behaviour of loudspeaker drivers, what facilities a driver needs under what circumstances - I have no idea.
There can be no scientific advances without innovation.
You like 'big stuff', so consider a 12" Subwoofer and a 12" Woofer in the same 100 litre cabinet. The subwoofer requires 80 litres for best performance and the woofer requires 50 litres. The bass guitarist strikes an 'E', the woofer tells the sub: "take whatever displacement you need, I can handle all the overtones and stuff in 20 litres". An Oboe strikes up. "Nothing for me do here," says the sub. "You can have the entire 100 litres to yourself."
If you can follow this logic: you now have a cabinet that is ultra-efficient at reduced power but disappoints under full load.
We can return the motorsport analogy and discuss how VVT became a thing but - innovation.
Please not respond to post without reviewing this link: SONY SS-S3 - YouTube
Only on crap drivers, not good ones from a reputable brand. As you've made the claim, give some specific examples with data please.
Not in my experience there aren't, but I'm willing to learn. Please state what these variables are.
What does your measurement system tell you? Human hearing is quite poor that low in frequency.
Based upon many, many successful completed projects that agreed very closely with the sims, I don't agree. Yet you have no experience and decide to slur those who do. Nice.
You are hilarious. By your own admission, "you have no idea" yet some of us have been designing and building LF enclosure for decades and you tell us we don't know what we're doing. Your lack of self awareness is astonishing.
Not seeing what the point of it was, except that it looks like it's getting fed signal below tune and the cone is therefore uncontrolled, something well known and understood for at least 40y.
(According to your logic) What happens if the oboe (midbass) is using all of the 100 litres and suddenly a big bass line kicks in as well? The oboe is now using its 20 litres and the frequency response of the midbass unit has had its response change from that of being in a 100 litre box to that of being in a 20 litre box. The subwoofer driver is now modulating the response of the midbass driver.
I know you don't like sim graphs but here's a Fane 12 in a closed box response. Green is the 'ideal 50 litres' as you stated. Red is its response playing in 100 litres when the sub is not doing anything. Blue is its response in 20 litres when the sub is playing 'E strings' etc.
According to your logic as soon as the bass guitar hits an E note the midbass response changes from the red curve to the blue curve. (-7dB to -12dB at 50Hz. If your ears can pick up a 3dB difference at 50Hz on your sofa they will really notice 50Hz getting 7dB louder / quieter everytime a bass guitar plays with an oboe on a track)
I recommended you buy a DATS setup a long time ago as you like to play with random drivers. You replied that it was not worth it. I'm wondering how you know that all the manufacturers data is rubbish if you are not measuring anything yourself ?
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Surtsey,
You do seem to enjoy stirring things up.
While speakers make no sound in simulations, it's up to the designer to determine what the graphs etc mean, once the speaker is built according to the simulated inputs.
Welcome to room acoustics. Walk around the room a little and you'll find much larger variations in SPL. In my room, I can find several spots where there is no 50Hz at all, despite considerable effort by the speakers.
That doesn't invalidate the speaker simulations.
Plenty of music below 35Hz, but it depends what you like to listen to. There are crazy people who listen to music with very strong infrasonics (<20Hz), but you need a lot of very serious subwoofers to experience it properly.
There are also movies to consider.
I'd suggest you've picked those frequencies (35Hz and 55Hz) arbitrarily, and in doing so, you've invalidated your own argument. More commonly accepted (and easier to defend) would be the main speakers getting to 80Hz, and the subwoofer(s) covering 20Hz-80Hz.
Whether bass has "finesse" is a subjective discussion that I'll leave to other posters.
Chris
You do seem to enjoy stirring things up.
While speakers make no sound in simulations, it's up to the designer to determine what the graphs etc mean, once the speaker is built according to the simulated inputs.
Welcome to room acoustics. Walk around the room a little and you'll find much larger variations in SPL. In my room, I can find several spots where there is no 50Hz at all, despite considerable effort by the speakers.
That doesn't invalidate the speaker simulations.
Plenty of music below 35Hz, but it depends what you like to listen to. There are crazy people who listen to music with very strong infrasonics (<20Hz), but you need a lot of very serious subwoofers to experience it properly.
There are also movies to consider.
I'd suggest you've picked those frequencies (35Hz and 55Hz) arbitrarily, and in doing so, you've invalidated your own argument. More commonly accepted (and easier to defend) would be the main speakers getting to 80Hz, and the subwoofer(s) covering 20Hz-80Hz.
Whether bass has "finesse" is a subjective discussion that I'll leave to other posters.
Chris
I like engaging with Chris661 - he knows his stuff. I'd still argue that my cross-over point is not arbitrary. Any serious audiophile has a decent set of mains. My Boston Acoustics are good down to 50Hz (-3dB) - that's where all the money went because that's where all the music is.
I have a pair of small subs covering the 50 - 35Hz range.
Beyond that I had a pair larger subs for everything below 40Hz.
Sidebar: I have a penchant for soul and eighties jazz-funk. All my big subs ever did was (1) Move random ornaments and objects leading me to believe I had a poltergeist, (2) Invoke sympathy vibrations from a door frame and the kitchen sink. (3) Remind me that my copy of Gil Scott Heron's "the Bottle" was slightly warped as the drivers hit Xmax in silence.
I maintain, there's nothing good down in the nether regions of the frequency range, and, if you insist on investigating - send disposable minimum wage workers.
Sidebar: the #1 mistake novices make in assembling x.1 systems . . . My desktop sub produces 88dB, the satellites are rated at 87dB - is that a good match?
Of course it's a trick question. There are four satellites (+6dB).
I have a pair of small subs covering the 50 - 35Hz range.
Beyond that I had a pair larger subs for everything below 40Hz.
Sidebar: I have a penchant for soul and eighties jazz-funk. All my big subs ever did was (1) Move random ornaments and objects leading me to believe I had a poltergeist, (2) Invoke sympathy vibrations from a door frame and the kitchen sink. (3) Remind me that my copy of Gil Scott Heron's "the Bottle" was slightly warped as the drivers hit Xmax in silence.
I maintain, there's nothing good down in the nether regions of the frequency range, and, if you insist on investigating - send disposable minimum wage workers.
Sidebar: the #1 mistake novices make in assembling x.1 systems . . . My desktop sub produces 88dB, the satellites are rated at 87dB - is that a good match?
Of course it's a trick question. There are four satellites (+6dB).
How do you know your 'Boston Acoustics are good down to 50Hz (-3dB)' ?
You are unable / un-willing to measure anything and you have already stated " However, I can establish that manufacturer's data is wildly inaccurate. "
You are unable / un-willing to measure anything and you have already stated " However, I can establish that manufacturer's data is wildly inaccurate. "
I suspect you're asking these questions for the sake of argument.
You go on-line and find a frequency signal generator (I believe WinISD has one). Lower the signal until the output begins to drop off.
I thought your thread title was an invitation for a 'discussion' ?
However it seems that any opinions that do not agree with yours are seen by you as 'arguments'
I wish my ears were good to 3dB in room.
btw, I agree with you that there is no finesse to a proper subwoofer and it should just fill in the almost 'un-hearable' bottom couple octaves.
The only 'finesse' comes in making sure that the subwoofer/s do not produce loads of harmonic distortion that end up louder than the actual subwoofers intended output, which then makes it very difficult for the subwoofer to blend in and 'disappear'
However it seems that any opinions that do not agree with yours are seen by you as 'arguments'
I wish my ears were good to 3dB in room.
btw, I agree with you that there is no finesse to a proper subwoofer and it should just fill in the almost 'un-hearable' bottom couple octaves.
The only 'finesse' comes in making sure that the subwoofer/s do not produce loads of harmonic distortion that end up louder than the actual subwoofers intended output, which then makes it very difficult for the subwoofer to blend in and 'disappear'
Rob Wells, a 3dB difference is easiest level to identify by ear. It's the difference between one speaker and two, centre balance vs extreme left or right.
The difference in level between one and two equally powered identical speakers located within 1/4 wave length of each other is 6 dB.
Center balance is dependent on the design of the circuit used.
Low frequency in room response level is dependent on speaker location and listening position, and can vary by 12dB or more within a meter, depending on room modes.
Center balance is dependent on the design of the circuit used.
Low frequency in room response level is dependent on speaker location and listening position, and can vary by 12dB or more within a meter, depending on room modes.
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Not sure I understand your example ? We were talking about subs around 50Hz which should not have any locational cues from the sub. But you are talking about identifying the 3dB difference from locational cues (extreme left or right)
Basically a 50Hz tone should not sound like it is coming from the subwoofer. If it does then you have problems.
Edit: If you have 2 subs, one next to your left and one next to your right main speakers, and play a 50Hz tone through them both and then disconnect one of them the sound should not 'move' to the sub still playing, it should just get a tiny bit quieter but still sound like it's coming from the same place.
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50hz enclosure = bass bin, not subwoofer.
If you are all about being "musical," then the lowest note of an 88 key piano is 27.5hz.
Sub-bass - Wikipedia
If you are all about being "musical," then the lowest note of an 88 key piano is 27.5hz.
Sub-bass - Wikipedia
We are not discussing direction. We are discussing "volume" and "SPL". I was asked how I could recognise a 3dB increase by ear. The answer is: it's the difference between one speaker and two speakers, two speakers being in twice as loud.
To engage in your of topic argument: A 50Hz sine wave is probably not that directional. But G1 (49Hz) on a piano probably is directional due to the overtones.
I'm afraid you're incorrect.
+3dB is what happens when you double the power delivered to a loudspeaker, assuming the speaker is still acting linearly.
+6dB is twice the physical pressure, and is equal to adding a second speaker in close proximity playing at equal amplitude. A simple examination of the radiating cone area and excursion confirms this.
+10dB sounds twice as loud in the mid-band - see equal loudness contours for more.
The directional properties of a concert grand are largely irrelevant here, but I'll include this link: Comparison of different microphone positions for orchestra instruments
Which is a very interesting project. It doesn't include a piano, but lots of classical instruments are present, and you can hear what they sound like from a wide range of angles.
Chris
+3dB is what happens when you double the power delivered to a loudspeaker, assuming the speaker is still acting linearly.
+6dB is twice the physical pressure, and is equal to adding a second speaker in close proximity playing at equal amplitude. A simple examination of the radiating cone area and excursion confirms this.
+10dB sounds twice as loud in the mid-band - see equal loudness contours for more.
The directional properties of a concert grand are largely irrelevant here, but I'll include this link: Comparison of different microphone positions for orchestra instruments
Which is a very interesting project. It doesn't include a piano, but lots of classical instruments are present, and you can hear what they sound like from a wide range of angles.
Chris
I stand corrected.
So, if I understand you correctly, two 8 ohm drivers in series off 3db over a single driver?
Coherent summation of multiple cabinets located within 1/4 wave length of each other should yield a 6 dB addition per doubling, +3 dB for doubling radiation area, and +3 dB for doubling power.
If two 8 ohm cabinets are run in series (16 ohms), the +3 dB from doubling radiation area equals the -3dB reduction in power compared to a single 8 ohm cabinet driven with the same voltage.
If two 8 ohm cabinets are run in series (16 ohms), the +3 dB from doubling radiation area equals the -3dB reduction in power compared to a single 8 ohm cabinet driven with the same voltage.
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