To my knowledge no one has used CMR in a PC, hence the numbers are only guesses, but since current data reductions stand at about 90%, there is only 10% left to reduce. Maybe the PC could guess at the audio being compressed and reduce it by 99-99.9%. Who knows.
I have no problem with the claims by the authors above. They seem perfectly reasonable, but they still don't imply that this is a major effect worth pursuing. People are always looking for improvements in this area, so they will look at just about anything, no matter how obscure and insignificant. A few % may well be worth doing, but it is still just a few %.
I have Fletcher's book and I could read it if I knew what he called it since he didn't call it CMR. I see no point in reviewing the entire text just to confirm your claim.
I have no problem with the claims by the authors above. They seem perfectly reasonable, but they still don't imply that this is a major effect worth pursuing. People are always looking for improvements in this area, so they will look at just about anything, no matter how obscure and insignificant. A few % may well be worth doing, but it is still just a few %.
I have Fletcher's book and I could read it if I knew what he called it since he didn't call it CMR. I see no point in reviewing the entire text just to confirm your claim.
Okay, but some of that sounds so bad as to be unlistenable. I don't listen to satellite radio in the car due to the lossy compression, can't stand it. Anything they can do to make some improvements is worth trying.
And that satellite radio is so bad is no excuse for fitting a car with poor speakers to go with it. Thankfully, i can still listen to CDs in the car, although hi-res would have been better.
Yea, so I'm not sure what the % compression has to do with the perceptual effects of ignoring the perceptual understanding of CMR. According to research it can change thresholds by anywhere between 4% & 18%. the much more interesting question is how often the particular conditions that gives rise to CMR occurs in music. Not sure if this has been evaluated?
Maybe I'm wrong about Fletcher - his experiments in this area related to his discovery & defining the critical bands models of perception & used noise masking to tease this out
Just as an aside - there is now an interactive sound demo of CMR here
It requires a browser that can run flash but it allows you to select the minimum (threshold) amplitude for audibility of a tone in noise. then it modulates the noise & your threshold drops - adjust the amplitude to the new min threshold & you have the change in threshold amplitude due to CMR
It requires a browser that can run flash but it allows you to select the minimum (threshold) amplitude for audibility of a tone in noise. then it modulates the noise & your threshold drops - adjust the amplitude to the new min threshold & you have the change in threshold amplitude due to CMR
More interesting findings. I took a driver using this coil and measured the inductance, pretty much the same value as the individual voice coil, 126uH. Then I dug up a version that had a shorting ring, 31.3uH. This is quite interesting.
It doesn't have to have look inductive to do work, remember. We want opposition to the flow of current to come from it acting as a motor and doing work, in which case it should look resistive.
In the case of motors I am familiar with, inductance is sometimes designed in to limit current flow if the motor is stalled. But, other than that they don't need to appear as inductive.
Dear friends,
Most of the 119 stick to other aspect, then in title.
I'm looking into sound transducers, and it is not easy to find a numbers. I mean a number of procent of distortion. Some producer like a Overview say only something like low, ultra low distortion, but it is not possible to compare between series, and between different producers, if the loudspeaker are really low distortion, or is it a marketing phrase.
I found on website SDR-DDR, some data about harmonic distortion and intermodulation distortion. If I understand proper figure 5, that mean the loudspeaker produce terrible amount of distortion 80% .......of what ....
That mean the 1% of the power amplifier are unnoticeable. Where is the truths ?
I hound that Mr. Linkwitz made some research, and show metrology of measurement Midrange distortion test. I bow my face to him.
Mr. Geedes could you explain clear the level of distortion, linear and nonlinear linear could be not recognized as distortion in the music. I'm a engineer and I really will know how good should be a power amplifier, and speaker that the distortion wouldn't be noticeable in the sound, by the average listener, not a train musician with gold ear.
Most of the 119 stick to other aspect, then in title.
I'm looking into sound transducers, and it is not easy to find a numbers. I mean a number of procent of distortion. Some producer like a Overview say only something like low, ultra low distortion, but it is not possible to compare between series, and between different producers, if the loudspeaker are really low distortion, or is it a marketing phrase.
I found on website SDR-DDR, some data about harmonic distortion and intermodulation distortion. If I understand proper figure 5, that mean the loudspeaker produce terrible amount of distortion 80% .......of what ....
That mean the 1% of the power amplifier are unnoticeable. Where is the truths ?
I hound that Mr. Linkwitz made some research, and show metrology of measurement Midrange distortion test. I bow my face to him.
Mr. Geedes could you explain clear the level of distortion, linear and nonlinear linear could be not recognized as distortion in the music. I'm a engineer and I really will know how good should be a power amplifier, and speaker that the distortion wouldn't be noticeable in the sound, by the average listener, not a train musician with gold ear.
I was listening to some old records through my array speakers with paper drivers and horn tweeters. I was amazed at how warm and rich the sound was.
I'm starting to think there is something to the whole euphonic distortion thing.
First, the assumption is always that accuracy in a transducer is the most important thing. But when you listen to music you don't analyze. Rather you get lulled into a relaxing right brain activity. The speaker sort of seduces you.
Thus a source-speaker-room combo that is relaxing creates this brain change quicker and easier. It's entirely possible that certain harmonics and also dispersion patterns are more relaxing, but not necessarily more accurate.
Another assumption I believe is false is that the speaker is supposed to remove itself from the sound. The problem here again is the assumption. What if our brains want and expect to hear subtle sounds and idiosyncracies from the speakers themselves, the subtle break up of a paper woofer for example. This adds cohesion that makes a performance, not just sound.
For example my pistonic PC controlled speakers that I built sound cleaner, but just don't lull me into the music the same way.
Blind tests aren't the way to measure this, because our preference over time will be for the sounds that we enjoy more, not necessarily accuracy.
I'm starting to think there is something to the whole euphonic distortion thing.
First, the assumption is always that accuracy in a transducer is the most important thing. But when you listen to music you don't analyze. Rather you get lulled into a relaxing right brain activity. The speaker sort of seduces you.
Thus a source-speaker-room combo that is relaxing creates this brain change quicker and easier. It's entirely possible that certain harmonics and also dispersion patterns are more relaxing, but not necessarily more accurate.
Another assumption I believe is false is that the speaker is supposed to remove itself from the sound. The problem here again is the assumption. What if our brains want and expect to hear subtle sounds and idiosyncracies from the speakers themselves, the subtle break up of a paper woofer for example. This adds cohesion that makes a performance, not just sound.
For example my pistonic PC controlled speakers that I built sound cleaner, but just don't lull me into the music the same way.
Blind tests aren't the way to measure this, because our preference over time will be for the sounds that we enjoy more, not necessarily accuracy.
Attachments
Don't let anyone tell you different.
Lots of hypotheses offered with no evidence. On the other hand, the other side, those "false assumptions" are supported by a great deal of evidence. This is the kind of rebuttal that always happens when one wants to believe what they want to believe even though it is contrary to the facts.
I've always interpreted as: it does not matter, once it's sufficiently down.
And with sufficiently down I aimed for 'at least' -40 dB at the listening seat for everything above ~ 40 Hz. Still working to get that first octave at a similar level (introducing a couple of subs) as it currently is about 35 dB down. I do doubt if that will result in a perceivable difference as far as distortion goes.
It might have other benefits though.
And with sufficiently down I aimed for 'at least' -40 dB at the listening seat for everything above ~ 40 Hz. Still working to get that first octave at a similar level (introducing a couple of subs) as it currently is about 35 dB down. I do doubt if that will result in a perceivable difference as far as distortion goes.
It might have other benefits though.
I have never said that "distortion" does not matter. Linear distortion, diffraction, both these matter. What one cannot do is use THD or IMD numbers as an indication of how something will sound, THEY simply don't matter. And I agree with Wesayso that once one gets below a certain level of nonlinear distortion it no longer matters. What that level actually is has never been clearly defined since, as I said, one cannot use THD or IMD numbers for this task.
Polkhigh made three claims that I disagree with based on the evidence:1) that accuracy is not what we want, that's not what Toole and Olive find; 2) that the loudspeakers should not "disappear", although not framed in those terms the same researchers find that accuracy and hence disappearance IS what people prefer; and last but not least 3) that "blind" is not correct - only blind studies have any validity. That is well known in all psycho-based research.
That question has been answered here so many times that I will not repeat it.
Sure its a legit question, but don't you think that it has been answered in this thread? I know it has, at least by me. But let me summarize:
1) linear distortion is the most consequential - overwhelmingly so.
2) nonlinear distortion can be lowered to the point of insignificance, but at no time can one use THD or IMD to determine if this has been met. So basically one just lowers all nonlinearities, but especially higher order one because they have much higher audibility (they are not masked).
3) some linear defects are more noticeable at higher SPL, like diffraction and some resonances. So judging "distortion" as a bad sound at higher SPL does NOT mean that it is nonlinear distortion. It could be linear.
1) linear distortion is the most consequential - overwhelmingly so.
2) nonlinear distortion can be lowered to the point of insignificance, but at no time can one use THD or IMD to determine if this has been met. So basically one just lowers all nonlinearities, but especially higher order one because they have much higher audibility (they are not masked).
3) some linear defects are more noticeable at higher SPL, like diffraction and some resonances. So judging "distortion" as a bad sound at higher SPL does NOT mean that it is nonlinear distortion. It could be linear.