If am playing 350hz and 400hz at the same time on a midrange, what will be resultant frequency it should be vibrating ?
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Driver movement
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That's transient response, and yes, is of utmost import. However, transient response is mathematically directly related to frequency response. Sometimes measurements show transient response, specifically impulse and/or step response, but they are usually not even measured directly; they are calculated from the frequency response.
"speed" or "fastness" of a driver is a lame term for transient response. driver can be fast enough to generate a 400Hz steady state signal, but it may be slower to response to a pulse or impulse function than another higher quality driver. the transient response depends on many factors, including the speaker's cabinet and size/shape of the port. I assume such transient response can be measured, but I never saw such measurement result.
(edit: added actual response
)Not a multiple, but sidebands are required to change the amplitude of a frequency component. However, these sidebands must be present in the recording for it to represent the transition, and they must be in your range of hearing for you to accurately hear the transition. So there's no point in the speaker being able to reproduce frequencies that are not contained in the recording or are not audible.
Both. You will know how the transducer behaves by measuring it. The result will tell you all you need to know.
If you want to argue further against this, the most basic aspect of wave theory, don’t be offended if I stop replying.
You are wrong.
But do we have to say what pattern here would be better.? I mean can't it be elastic like it goes front and then slowly goes back without any ringing or it can ring but each ring is considerably lower in intensity until it dies. What could be more audible?
How can a cone vibrate in more than one frequency at a time?I understand it does but how is baffling me always. If we measure the frequency swipe it's understandable. But if we do a multi tone how does it work ? I think it it will be a complex functionathemagically. But what will be its translation to number of virbations? Also parts of a cone vibrates in different frequencies?
JRS
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Also the BL product and mass of the driver, the ratio of which is acceleration. But yes, the biggest problem is the resonance of the driver + box + port + EQ all contributing to the transfer function and ultimate time domain behavior. The driver resonance behavior can be visualized with a waterfall plot.
Unless I got the 101 course wrong. ;-D Which is an ongoing online course--thanks guys!
dshreter
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@TheWalkman touched on this, but I'll extend the thoughts a little further.
A loudspeaker is designed to operate as a transducer, not like a spring. Let's ignore the interaction between the driver and the cabinet for a moment and just focus on the output, it is meant to produce air movement that corresponds to the electrical input, and it is specifically designed to reduce resonance. With music, these are continuous wave forms, and the drivers are continuously moving with the signal. It doesn't move at 400 Hz, stop, then start moving at 800 Hz to play different notes. Rather in real sounds you have contributions at many frequencies all the time. Even for a single tone of of a violin playing an A, real sounds have harmonics at multiple frequencies.
Looking in the time domain, how does the amplitude vary with time from left to right, the wave form might look something like this. It doesn't really look like a sin wave, and that's what the forward and back driver movement looks like too. This is a G played on a violin, and you can see a speaker doesn't exactly go from playing one frequency to the next.
You can analyze this in the frequency domain for a totally different perspective. You can see that same G has a fundamental, but then there are harmonics extending way out. All of those frequencies added together are what give you the wave form you see above.
Hopefully seeing the above it becomes clearer that a speaker's job is to tranduce, or match, the signal going into it regardless of complexity. To do that job faithfully we measure the frequency response (for any frequency input, how much of that frequency do you get as output), and also measure the distortion (for any frequency in, how much of other frequencies do you get out).
Speakers aren't perfect though, and one of your intuitions is right that a speaker can't instantaneously jump from one state to the next. Take this example of feeding a speaker a square wave which is basically hell for how a driver naturally wants to move. You can see the response is far from perfect.
www.whatsbestforum.com
To your original question about how a speaker behaves when moving from one frequency to the next, you can describe any musical signal as the sum of the frequency components like the purple chart above. Going from 40 Hz to 33 Hz in your example, looks like a sin wave at 40 Hz that turns into a sin wave at 33 Hz in the time domain. In the frequency domain though if you ran a fourier transform on the signal, you would see at the transition time that it looks like many different frequencies that can be added together that can recreate that complex waveform. The speaker's ability to create each of those frequencies with linearity and low distortion corresponds to the ability to play that sound accurately.
A loudspeaker is designed to operate as a transducer, not like a spring. Let's ignore the interaction between the driver and the cabinet for a moment and just focus on the output, it is meant to produce air movement that corresponds to the electrical input, and it is specifically designed to reduce resonance. With music, these are continuous wave forms, and the drivers are continuously moving with the signal. It doesn't move at 400 Hz, stop, then start moving at 800 Hz to play different notes. Rather in real sounds you have contributions at many frequencies all the time. Even for a single tone of of a violin playing an A, real sounds have harmonics at multiple frequencies.
Looking in the time domain, how does the amplitude vary with time from left to right, the wave form might look something like this. It doesn't really look like a sin wave, and that's what the forward and back driver movement looks like too. This is a G played on a violin, and you can see a speaker doesn't exactly go from playing one frequency to the next.
The Fourier Transform and the Spectrum - Tremblings and Warblings
How does one obtain the spectrum of a sound? By using the Fourier theorem, which states that any periodic waveform can be broken down into sine waves.
www.tremblingsandwarblings.com
You can analyze this in the frequency domain for a totally different perspective. You can see that same G has a fundamental, but then there are harmonics extending way out. All of those frequencies added together are what give you the wave form you see above.
The Fourier Transform and the Spectrum - Tremblings and Warblings
How does one obtain the spectrum of a sound? By using the Fourier theorem, which states that any periodic waveform can be broken down into sine waves.
www.tremblingsandwarblings.com
Hopefully seeing the above it becomes clearer that a speaker's job is to tranduce, or match, the signal going into it regardless of complexity. To do that job faithfully we measure the frequency response (for any frequency input, how much of that frequency do you get as output), and also measure the distortion (for any frequency in, how much of other frequencies do you get out).
Speakers aren't perfect though, and one of your intuitions is right that a speaker can't instantaneously jump from one state to the next. Take this example of feeding a speaker a square wave which is basically hell for how a driver naturally wants to move. You can see the response is far from perfect.
Square Wave Response, Measured Acoustically
Most of us know that trying to acoustically reproduce a square wave is an exercise in futility. I've tried it with decent headphones, by mounting a measurement mic in the earpiece and sealing it off, but the result didn't even resemble anything like a square wave. Doing it with multiway speakers...
www.whatsbestforum.com
To your original question about how a speaker behaves when moving from one frequency to the next, you can describe any musical signal as the sum of the frequency components like the purple chart above. Going from 40 Hz to 33 Hz in your example, looks like a sin wave at 40 Hz that turns into a sin wave at 33 Hz in the time domain. In the frequency domain though if you ran a fourier transform on the signal, you would see at the transition time that it looks like many different frequencies that can be added together that can recreate that complex waveform. The speaker's ability to create each of those frequencies with linearity and low distortion corresponds to the ability to play that sound accurately.
The last answer was convincing but then again can you tell me in number of vibrations a cone should move in a second if I play a tone mixed with a 350 and 450 Hz simultaneously? If a single signal is playing it shoud be a number in time domain like for 40hz it would be 33hz like I the above post. But what would be a number for two tones at the same time. Is there a formula to find it?
How does a cone movement correspond to a complex waveform? How many strokes in other words?
How does a cone movement correspond to a complex waveform? How many strokes in other words?
OP
BrokenEnglishGuy
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So a speaker that it's low in distortion, have a linear FR and the cabinet doesn't have resonances, the wavelength that are going to create gonna be very good in the '' time domain '' and accurate ?@TheWalkman touched on this, but I'll extend the thoughts a little further.
A loudspeaker is designed to operate as a transducer, not like a spring. Let's ignore the interaction between the driver and the cabinet for a moment and just focus on the output, it is meant to produce air movement that corresponds to the electrical input, and it is specifically designed to reduce resonance. With music, these are continuous wave forms, and the drivers are continuously moving with the signal. It doesn't move at 400 Hz, stop, then start moving at 800 Hz to play different notes. Rather in real sounds you have contributions at many frequencies all the time. Even for a single tone of of a violin playing an A, real sounds have harmonics at multiple frequencies.
Looking in the time domain, how does the amplitude vary with time from left to right, the wave form might look something like this. It doesn't really look like a sin wave, and that's what the forward and back driver movement looks like too. This is a G played on a violin, and you can see a speaker doesn't exactly go from playing one frequency to the next.
The Fourier Transform and the Spectrum - Tremblings and Warblings
How does one obtain the spectrum of a sound? By using the Fourier theorem, which states that any periodic waveform can be broken down into sine waves.www.tremblingsandwarblings.com
You can analyze this in the frequency domain for a totally different perspective. You can see that same G has a fundamental, but then there are harmonics extending way out. All of those frequencies added together are what give you the wave form you see above.
The Fourier Transform and the Spectrum - Tremblings and Warblings
How does one obtain the spectrum of a sound? By using the Fourier theorem, which states that any periodic waveform can be broken down into sine waves.www.tremblingsandwarblings.com
Hopefully seeing the above it becomes clearer that a speaker's job is to tranduce, or match, the signal going into it regardless of complexity. To do that job faithfully we measure the frequency response (for any frequency input, how much of that frequency do you get as output), and also measure the distortion (for any frequency in, how much of other frequencies do you get out).
Speakers aren't perfect though, and one of your intuitions is right that a speaker can't instantaneously jump from one state to the next. Take this example of feeding a speaker a square wave which is basically hell for how a driver naturally wants to move. You can see the response is far from perfect.
Square Wave Response, Measured Acoustically
Most of us know that trying to acoustically reproduce a square wave is an exercise in futility. I've tried it with decent headphones, by mounting a measurement mic in the earpiece and sealing it off, but the result didn't even resemble anything like a square wave. Doing it with multiway speakers...
To your original question about how a speaker behaves when moving from one frequency to the next, you can describe any musical signal as the sum of the frequency components like the purple chart above. Going from 40 Hz to 33 Hz in your example, looks like a sin wave at 40 Hz that turns into a sin wave at 33 Hz in the time domain. In the frequency domain though if you ran a fourier transform on the signal, you would see at the transition time that it looks like many different frequencies that can be added together that can recreate that complex waveform. The speaker's ability to create each of those frequencies with linearity and low distortion corresponds to the ability to play that sound accurately.
And if the driver have not enough self dampening material and cannot create these waves accurate, its gonna show that as distortion ?
ty
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BrokenEnglishGuy
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I'm guessing but if these 2 frequency sound at the same time it not will be any problem because these wavelength are creating in different time, so these 2 40 hz and 33 hz can sound simultaneously (?) they can co exist simultaneously
dshreter
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Bingo. Having a cabinet without resonances ties back to low distortion and linear FR. Accuracy in the time domain and the frequency domain translates to the same outcome, it's just analyzing it from a different perspective, much like the audio signal can be viewed as amplitude vs time or amplitude vs frequency. It's a bit of a mind-blowing concept actually.
dshreter
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The cone doesn't move simply move in a number of cycles per second. It actually moves like this, which is to say all over the place. You can't simply describe that as cycles per second because there are many simultaneous frequency components.
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BrokenEnglishGuy
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Well that explain why it's mandatory integrate correctly the bass into the room.., when i fixed the bass in my room, the bass start to dissapiar of the room and everything sounds more clean, clear and more correct
I thinked i had a bad reververation in my room but once i fixed the bass it's sound very different..
Ha! Do you want to be convinced when the loudspeaker model is mathematically and psychically explained 50 years ago? This is borderline antivaccination malarkey!
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BrokenEnglishGuy
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I remember a guy here, that post this graph pointing the woofer have problems.
These problems are translate into stuff like ' dullness ', ' never rest ', ' clarity ' to him
This is the woofer from the 2011 R series and he said:
''WTF
It never came to a complete hault even when first reflection arrived at 10.3ms - i never saw anything like this except in few car subs that also use two part cone (oval and cone part glued). This must be the dirtiest impulse response in a hifi woofer i measured so far.''
So, this graph what does mean? It's the R300.
''
These problems are translate into stuff like ' dullness ', ' never rest ', ' clarity ' to him
This is the woofer from the 2011 R series and he said:
''WTF
It never came to a complete hault even when first reflection arrived at 10.3ms - i never saw anything like this except in few car subs that also use two part cone (oval and cone part glued). This must be the dirtiest impulse response in a hifi woofer i measured so far.''So, this graph what does mean? It's the R300.
''
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