Very unsatisfactory answer that tells a lot.
Do you know how they measure a Kilogram, Just a guy?
There is a reference Kg weight. Somewhere in France, that reference Kg is kept under precious surveillance. Fabulous, uh? Don't take my word for it, google it.
The lack of reference is THE single biggest problem in audio reproduction.
There is no absolute reference kept under surveillance anywhere. There is no microphone that simulates the ear capacities of any human, even less a human considered a reference for the species and even less a reference for all humans.
You CANNOT calibrate a transducer other than compensating the signal (via a mic file that adjusts the FR, based on a non-existing reference mic). A mic is a transducer just like a speaker driver. Nothing more, nothing less. With similar limits and potential defects and innacuracy from a unit to another.
Calibrated is just a word left out by the Marketing dept...
no i got that allright with your explanations, really, but what about NAUSEA ?
Studies were made about infrabass, isnt it? How do we say eolienne in english? That. Some people are annoyed by the constant drone they generate. They start to wonder if that affect health on long term.
I'm not saying it not healthy, i'm just saying it raises questions.
You can't hear below 20hz, i get it. You FEEL it. Then, if you feel it, we're talking potential BODY damage, am i wrong ?
Very unsatisfactory answer that tells a lot.
Do you know how they measure a Kilogram, Just a guy?
There is a reference Kg weight. Somewhere in France, that reference Kg is kept under precious surveillance. Fabulous, uh? Don't take my word for it, google it.
The lack of reference is THE single biggest problem in audio reproduction.
There is no absolute reference kept under surveillance anywhere. There is no microphone that simulates the ear capacities of any human, even less a human considered a reference for the species and even less a reference for all humans.
You CANNOT calibrate a transducer other than compensating the signal (via a mic file that adjusts the FR, based on a non-existing reference mic). A mic is a transducer just like a speaker driver. Nothing more, nothing less. With similar limits and potential defects and innacuracy from a unit to another.
Calibrated is just a word left out by the Marketing dept...
Is this a joke or are you being serious? Where do you think "gram" came from? It's the weight of 1 mm of water. You can use a handy conversion program if that's too complicated.
An externally hosted image should be here but it was not working when we last tested it.
You calibrate a mic by measuring a sound source with a very expensive mic that has itself been calibrated to have a flat frequency response. The calibration reference mic costs THOUSANDS of dollars.
Then you measure the same sound source with any other mic in the world. Then you create a calibration file that when entered into any measurement program will make the mic measurements flat. It's the CALIBRATION FILE that makes the measurements from the mic flat, you are not physically operating on the mic capsule to somehow make sure it measures perfectly flat response.
I use REW and it's a simple 1 click operation to load up the cal file that was provided with my professionally calibrated mic.
I'm extremely surprised you've never heard of a professionally calibrated mic. Literally the entire industry uses them and now they are cheap enough for diy'ers too.
no i got that allright with your explanations, really, but what about NAUSEA ?
Studies were made about infrabass, isnt it? How do we say eolienne in english? That. Some people are annoyed by the constant drone they generate. They start to wonder if that affect health on long term.
I'm not saying it not healthy, i'm just saying it raises questions.
You can't hear below 20hz, i get it. You FEEL it. Then, if you feel it, we're talking potential BODY damage, am i wrong ?
Sure, some people puke. Some people don't. Do you get physically sick from an earthquake? I don't. I get seasick but low frequencies and earthquakes don't bother me. And they certainly don't damage my body. Again ... astronauts ...
LOL, I can't even believe this website conversion calculator even exists. It's a 1:1 relationship. No matter what number of ml you type in you will always get the same number in grams. This is too funny, but it's out there.
Tonight i'm discovering the HT circle. I'm terrified.
No women i guess, uh? Like always, just a bunch of lunatic mens with too much spare time. When do we start? So you recommend 8 or 12 18 inchers to begin with ?
Very unsatisfactory answer that tells a lot.
Do you know how they measure a Kilogram, Just a guy?
There is a reference Kg weight. Somewhere in France, that reference Kg is kept under precious surveillance. Fabulous, uh? Don't take my word for it, google it.
The lack of reference is THE single biggest problem in audio reproduction.
There is no absolute reference kept under surveillance anywhere. There is no microphone that simulates the ear capacities of any human, even less a human considered a reference for the species and even less a reference for all humans.
You CANNOT calibrate a transducer other than compensating the signal (via a mic file that adjusts the FR, based on a non-existing reference mic). A mic is a transducer just like a speaker driver. Nothing more, nothing less. With similar limits and potential defects and innacuracy from a unit to another.
Calibrated is just a word left out by the Marketing dept...
Are you being deliberately obtuse? That's like saying "show me a volt! how can you know your voltmeter reads accurate volts?"
The microphone is calibrated with precise equipment that is known to be accurate, which in turn is calibrated by even more expensive equipment that can be shown to be accurate to fractions of dBs not even worth considering in the loudspeaker world.
The CSL microphones are as accurate as you'd ever need for speaker building.
Fifty 18"
Fifty 18 inch woofers in suitable cabinets might not fit in my room, or allow me to fit. I'm not sure I want more than 115dB anyway, and the eminent tech says ">115dB". If it can do 115dB at 1 Hz, that's quite an achievement I think. Are you sure your 50x 18s will do 115dB at 1 Hz?
OK, the rotary wouldn't exactly "fit" either as it needs a basement or something, but still it leaves more space for other activity.
Also the rotary solution seems far more elegant to me, and if you need more power, it seems it could be made a little bigger.
I see and hear the strain in large woofers making bass at 20Hz with a mere 100dB. It seems to me the rotary isn't working against nature by squeezing air into a box, it's more working like nature by blowing air around.
The woofer boxes will also have lots of delayed resonances combined with omnidirectional radiation that stimulates room modes far more than dipolar speakers. While the infinite baffle rotary woofer is still going to stimulate room modes more than a dipole, it also seems you could re-arrange the infinite baffle to make it an infinite ported baffle with a second opening to the basement, and thereby mitigating modes.
In my experience, getting deep bass where you have room modes to contend with, mitigating the modes becomes far more difficult than simply adding more bass output.
Fifty 18 inch woofers in suitable cabinets might not fit in my room, or allow me to fit. I'm not sure I want more than 115dB anyway, and the eminent tech says ">115dB". If it can do 115dB at 1 Hz, that's quite an achievement I think. Are you sure your 50x 18s will do 115dB at 1 Hz?
OK, the rotary wouldn't exactly "fit" either as it needs a basement or something, but still it leaves more space for other activity.
Also the rotary solution seems far more elegant to me, and if you need more power, it seems it could be made a little bigger.
I see and hear the strain in large woofers making bass at 20Hz with a mere 100dB. It seems to me the rotary isn't working against nature by squeezing air into a box, it's more working like nature by blowing air around.
The woofer boxes will also have lots of delayed resonances combined with omnidirectional radiation that stimulates room modes far more than dipolar speakers. While the infinite baffle rotary woofer is still going to stimulate room modes more than a dipole, it also seems you could re-arrange the infinite baffle to make it an infinite ported baffle with a second opening to the basement, and thereby mitigating modes.
In my experience, getting deep bass where you have room modes to contend with, mitigating the modes becomes far more difficult than simply adding more bass output.
it's a lot more complex than that:
Litre - Wikipedia
And yet, that's a very simplistic topic (weight, water volume references)... A lot simplier than audio reproduction systems and physio-psycho acoustic perceptions.
Litre - Wikipedia
And yet, that's a very simplistic topic (weight, water volume references)... A lot simplier than audio reproduction systems and physio-psycho acoustic perceptions.
Guys, REFERENCES are either based on conventions (''we all agree'') or possible ways to perfectly duplicates said reference by external means (platinum-iridium cylinder for the Kg) with precise specs and stable elements.
Audio reproduction?
ISO 226:2003 ? That's your platinum-iridium cylinder ? That's your atomic clock ?
Your so-called primo reference mic is based on what exactly?
How far is it from my Earthworks M50 ?
What makes the M50 less perfect ? Please explain in details, be more specific, please. Want to know about the mic construction, diaphragm size, Fs, etc...
Audio reproduction?
ISO 226:2003 ? That's your platinum-iridium cylinder ? That's your atomic clock ?
Your so-called primo reference mic is based on what exactly?
How far is it from my Earthworks M50 ?
What makes the M50 less perfect ? Please explain in details, be more specific, please. Want to know about the mic construction, diaphragm size, Fs, etc...
I already told you, fifty 18s can be housed in 10 manifolds measuring 18x18x18 inches. That's not very big. And the manifold can stick into the adjacent room if you like, meaning the entire 50 driver IB would take up zero space in your listening room.
Infinite baffle does not have any air resistance to work against like a small sealed box would.
If you think conventional drivers sound stressed when playing low notes, did you watch the video I posted of the rotary sub? It loud as all heck and the guy standing there was concerned that it was going to come apart and kill everyone.
Porting an IB system will not mitigate room modes in any way.
That doesn't matter though, because unless the room is HUGE, like over 30 feet long, there aren't going to be any room modes in the 1 - 20 hz frequency range.
If you absolutely require sims I can easily prove that 50 18s will absolutely SMASH a rotary woofer. At all frequencies.
You also have to remember that unless you shop very wisely or get extremely lucky you won't get too much lower than 10 hz anyway. Every single component in your system is going to have some amount of low frequency roll off. All the components in the chain will have a cumulative roll off. This could start as high as 30 hz in a lot of consumer grade electronics.
Unless you go cutting the input coupling caps out of every piece of electronics in the chain even the rotary sub isn't going to be playing 1 hz at any spl. It's probably going to be lucky to get 3 hz unless you specifically pick all your equipment to make sure it can actually play that low.
Originally defined as "the absolute weight of a volume of pure water equal to the cube of the hundredth part of a metre, and at the temperature of melting ice"[2] (later at 4 °C, the temperature of maximum density of water).
Gram - Wikipedia
Sure, they've come up with an even more accurate reference now that they do keep locked up in France, but the original reference was certainly more than good enough for the girls I go out with.
How accurate do we really need to get here? My bathroom scale is off by about 10 lbs, it doesn't cause me any anxiety. The original water reference was way more than good enough.
EDIT - yes I meant 1 ml, not mm
That is just the standard silly answer: ''even more expensive equipment'' (!!)
WELL if it costs more, should be good, uh!
yeaah, i'm rolling eyes. They're almost stucked.
''is known to be accurate''... Again, evasive manoeuvers. Is known HOW? (other than price tag)
A transducer is a transducer. It will work accurately into a LIMITED bandwith at a LIMITED amplitude, there is no way around it. No way.
I'm using a pair of M50 because it's the less doubtful (subjectively speaking!) in regards of first and last octaves, that i tried so far. Perfect? Hell no? Trustworthy? I wouldnt even dare to believe that!
The technology is not there, where a mic can mimic the human earing system. I'd say, not even close.
Psycho acoustics and FM curves and ISO two thousand whatever have nothing to do with this. SPL is SPL and it has nothing to do with how we perceive it as humans. Perception is a whole other (completely unrelated) topic.
Are you saying that all mics in the world are useless because there's no universal standard?
I'm pretty sure the sciencey guy have a pretty good handle what what reference spl is. I don't know how and I don't care to look it up but I trust calibrated mics to be WAY more accurate than I'll ever need.
I can see now my rotary dream has some downsides. Thanks for some critical information there. But I don't comprehend how I'm going to fit 50x 18's in any way or shape either. How big does the hole in the wall need to be??? Do you have a drawing or diagram of this manifold?
All my signal processing including level adjustment is digital. The digital feeds a DC coupled DAC which feeds my DC coupled amplifier. I have no problem creating 1 Hz...more recently I had problem with DC frying my electrostat transformers.
just a guy, that maybe over-the-top accuracy for us, but not for scientists.
Audio reproduction reference ? Oh man! We're so far from your bathroom scale accuracy, you can't imagine! Basically, you'd be happy to weigh anywhere between a three-legged mouse and a pregnant elephant ;-)
Our actual technology just don't allow any audio reproduction that is realistic. Period.
A real trumpet cannot be audiocopied. A real drum even less. The sound of the real thunder at 100ft. even less. Niagara waterfalls, even less.
I dare you: blind test it. With as much people it's needed. You'll struggle just to find naturally emitted SOUNDS so simplistic it can be audiocopied and reproduced so its 100% impossible for the blinded person to identify which is which 20 times out of 20 (or 17 times of of 20 if we're being statistically coherent).
A real concert with 50 musicians and the crowd?
Ha. HAHAHA.
Audio reproduction reference ? Oh man! We're so far from your bathroom scale accuracy, you can't imagine! Basically, you'd be happy to weigh anywhere between a three-legged mouse and a pregnant elephant ;-)
Our actual technology just don't allow any audio reproduction that is realistic. Period.
A real trumpet cannot be audiocopied. A real drum even less. The sound of the real thunder at 100ft. even less. Niagara waterfalls, even less.
I dare you: blind test it. With as much people it's needed. You'll struggle just to find naturally emitted SOUNDS so simplistic it can be audiocopied and reproduced so its 100% impossible for the blinded person to identify which is which 20 times out of 20 (or 17 times of of 20 if we're being statistically coherent).
A real concert with 50 musicians and the crowd?
Ha. HAHAHA.
At the frequency extremes the human ear is absolutely terrible. Mics are WAY better. The human ear is pretty good in the 1 - 4 khz range but that's about it. Outside of that range it gets worse and worse until you can't hear anything at all. The mic does just fine in these ranges, especially if it's calibrated.
Just because you can't pick out things like "imaging" on a picture of measured frequency response doesn't mean that mics are inferior to ears. This is the kind of thing die hard audiophiles like to say. Science rarely agrees with anything audiophiles say.
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