good luck with that.
of course the spl was not the same at each frequency, no small box unfiltered alignment will have a flat frequency response to begin with. If they did, we would have so much fewer troubles as diy speaker builders, LOL.
Even the recent Beyma addition would also suffer slightly from such distortions as it was tested pretty much identically, as much as a simplistic test method will allow. So, I stand by my statement that they are all on the same level playing field. If you want more aaccurate measurements, feel free to take on an endeavor like this.
since you sponsored me a little bit, I will accommodate your request.
Please specify the following for the re-test of the Beyma 10MC700Nd (only):
How many oz of stuffing? (Currently is 8oz)
distance from Mic to speaker?
Drive level? (Vrms)
Updated data, as per request of a DIY member who sent a pair of old school JBL 2012HPL 10" mids. Conditions were identical to the other set of measurements I had made, even if they were a bit flawed. The reason for this was for the sake of consistency so I could graph the data together with the rest with all of them on the same level playing field. As with the rest of the speakers, these are a bit "cleaner than the numbers indicate". No I will not re-test.
Frequency Response 2.83V @ 1m, both speakers. Pretty consistent across the board.
Harmonic Distortion dB chart(s). All of these HD charts are with a sharp filter @ 4k to prevent the bump in the upper-midrange from overdriving the Omnimic prematurely so I could get the same SPL level out of the speaker @ 500Hz like I did with the other ones.
Unit #1
Unit #2
Harmonic Distortion Percentage Charts
Comparisons with my 10's.
Frequency Response 2.83V @ 1m, both speakers. Pretty consistent across the board.
Harmonic Distortion dB chart(s). All of these HD charts are with a sharp filter @ 4k to prevent the bump in the upper-midrange from overdriving the Omnimic prematurely so I could get the same SPL level out of the speaker @ 500Hz like I did with the other ones.
Unit #1
Unit #2
Harmonic Distortion Percentage Charts
Comparisons with my 10's.
Thanks. You can try to listening to music and then doubling(=16) the amount of stuffing, perhaps you hear the mid range area with more detail?
Distance that is the most commonly used is 0.5 meters.
Drive level should be something not to clip the mic in any circumstance, difficult to say what is the optimum in your case, just keep it in the safe side.
Will do.
The limit to the mic for the specific purpose of measuring THD is 120dB, so I will keep it to 115 dB for the new tests to stay on the safe side.
I wish someone would have sponsored Oscar some of the more expensive drivers to see if they are worth their asking figure... I'd love to see some independent database of drivers actual performance... even more awesome if that person added that data to some modelling software for us all to use
as many know on the forum here there is no best driver, only the best driver for a job. As already pointed out by some the 10" driver application here was not defined in terms of Xover points, power output or off-axis performance etc.
Also the rock/metal/death metal and electric guitar reproduction renders the distortion measurements totally amiss (IMHO). The proof are guitar amplifiers and speakers which are designed to distort. You should probably measure some Eminence drivers made for such an application and then listen to them.
Even in a typical "audiophile" application here where people care the most about vocal and classic instruments reproduction the merits of pure tone distortion measurements are doubtful as Geddes argued at length based on some blind studies performed (probably from his workplace while still active).
On the other hand the smoothness of the frequency response including off-axis performance matters; one can see that by the new metrics for tonal noise assessments like "the prominence ratio" working their way from ECMA to ISO standards (metric is already built into the professional software used in the industry for tonal noise assessments). One can get a power point file from Wade Bray with embedded audio files demonstrating the tonal quality of bands as wide as 1kHz if raised sharply above the background noise which makes the "rolling landscape" of the FR important. This is all in agreement with the current understanding of human hearing based on integrating sound over 24 bands a.k.a. barks. CSD can also communicate some info which may have merits for a particular application.
View attachment 1355 Bray A New Psychoacoustic Method for Reliable Measurement of Tonalities According to Percep.pdf
Also the rock/metal/death metal and electric guitar reproduction renders the distortion measurements totally amiss (IMHO). The proof are guitar amplifiers and speakers which are designed to distort. You should probably measure some Eminence drivers made for such an application and then listen to them.
Even in a typical "audiophile" application here where people care the most about vocal and classic instruments reproduction the merits of pure tone distortion measurements are doubtful as Geddes argued at length based on some blind studies performed (probably from his workplace while still active).
On the other hand the smoothness of the frequency response including off-axis performance matters; one can see that by the new metrics for tonal noise assessments like "the prominence ratio" working their way from ECMA to ISO standards (metric is already built into the professional software used in the industry for tonal noise assessments). One can get a power point file from Wade Bray with embedded audio files demonstrating the tonal quality of bands as wide as 1kHz if raised sharply above the background noise which makes the "rolling landscape" of the FR important. This is all in agreement with the current understanding of human hearing based on integrating sound over 24 bands a.k.a. barks. CSD can also communicate some info which may have merits for a particular application.
View attachment 1355 Bray A New Psychoacoustic Method for Reliable Measurement of Tonalities According to Percep.pdf
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The reproduction of a distorted guitar tone (which is produced by over-driven tube amps, mostly) is still of interest, because to ME that is the pure tone I'm looking to enjoy listening to from a recording. Using your 'eminence drivers made for such an application' simply does not apply. Letting them distort on the play-back side to attempt to reproduce the tone that is already perfectly distorted from tubes is simply a whack idea, because in a recording there is plenty more that needs to be reproduced, not just the electric guitar. So IMHO your justification of rendering the distortion measurements totally amiss, is totally amiss.
the main point was that a lot more different measurements are needed to try to characterize a driver and still one has to listen to them in the end, and a particular application has to be considered because they each excel in a certain configuration. Xover work matters and the naked driver measurements as far as distortion only so much.
As far as your insisting on a "clean" reproduction of a signal recorded by a microphone: if that say eminence driver was able to reproduce that over-driven tube signal from the guitar the first time around and put it in the air for the microphone to record it, what makes you think it will not be able to reproduce it again on the play back? Oh, you think it will add more distortion, right? Even if it did at least you will get the same distortion pattern instead of another one from a different driver (you can see that they all are in the same ballpark distortion-wise so if you think that your driver will be some kind of "a truth machine" with a couple of orders lower distortion than that "Eminence" which made the sound the first time around and which now the new driver is trying to emulate, you should think again).
The main point again is not to get hung up on a simple pure tone distortion measurement because there is a lot more to psychoacoustics and how the human hearing works. Linkwitz already explained that unless you make a binaural recording with microphones stuck into your ear canals and play that back through the headphones (btw I did it with professional equipment provided by the author of that paper I shared with you), everything else in the music reproduction is an illusion as far as the sound field goes at the listener position in another room with some speaker setup replaying sound from an arbitrary point in the recording sound field where a microphone was used to capture one instrument at a time or multiple instruments simultaneously and then all mixed at a table by another person listening to it through headphones or through some monitors: everything in the recording process is so far from giving you the same experience that the whole playback is just about combining all kinds of distortions all over again hoping to arrive at something which is just pleasing in nature; there is no such thing as "high fidelity" because it lacks definition to begin with. It is quite plausible that on a playback to the listener in his/her room a particular voice say may sound even more pleasing than the real one would in a different venue (where btw even a seat placement would make a difference) and there is nothing wrong with that. Moreover the brain can adjust to a lot and also unluckily it comes predisposed with expectations set by previous experiences etc. In other words beating a simple measurement to death and trying to pass a judgment on a driver comparison based solely off of those curves has little merit.
As far as your insisting on a "clean" reproduction of a signal recorded by a microphone: if that say eminence driver was able to reproduce that over-driven tube signal from the guitar the first time around and put it in the air for the microphone to record it, what makes you think it will not be able to reproduce it again on the play back? Oh, you think it will add more distortion, right? Even if it did at least you will get the same distortion pattern instead of another one from a different driver (you can see that they all are in the same ballpark distortion-wise so if you think that your driver will be some kind of "a truth machine" with a couple of orders lower distortion than that "Eminence" which made the sound the first time around and which now the new driver is trying to emulate, you should think again).
The main point again is not to get hung up on a simple pure tone distortion measurement because there is a lot more to psychoacoustics and how the human hearing works. Linkwitz already explained that unless you make a binaural recording with microphones stuck into your ear canals and play that back through the headphones (btw I did it with professional equipment provided by the author of that paper I shared with you), everything else in the music reproduction is an illusion as far as the sound field goes at the listener position in another room with some speaker setup replaying sound from an arbitrary point in the recording sound field where a microphone was used to capture one instrument at a time or multiple instruments simultaneously and then all mixed at a table by another person listening to it through headphones or through some monitors: everything in the recording process is so far from giving you the same experience that the whole playback is just about combining all kinds of distortions all over again hoping to arrive at something which is just pleasing in nature; there is no such thing as "high fidelity" because it lacks definition to begin with. It is quite plausible that on a playback to the listener in his/her room a particular voice say may sound even more pleasing than the real one would in a different venue (where btw even a seat placement would make a difference) and there is nothing wrong with that. Moreover the brain can adjust to a lot and also unluckily it comes predisposed with expectations set by previous experiences etc. In other words beating a simple measurement to death and trying to pass a judgment on a driver comparison based solely off of those curves has little merit.
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Thanks. I could not get the values to display correctly within my graphs, because mine already have the horizontal points in a log scale and thus can be plotted linearly, where as yours are linear, and then the program condenses the view into a logarithmic style. None the less, it is indeed worth taking a look at.
the subject is not a guitar driver but the measurements of drivers in this thread and the interpretation of these. here it is from a PhD in the field of acoustic design:
Geddes on Distortion perception
btw the low order distortion being pleasing is also evident in First Watt amp designs by Pass.
I keep getting a reference to "reproduction": What are you exactly trying to reproduce? there is no even a standard in the recording industry to begin with, for microphone placement, room treatment or equipment used; not to mention sound mixing and EQing by a random individual.
And how are you to reproduce sound coming from different sources physically apart by playing it all out of say two speakers in a different room? the whole "stereo reproduction" etc is an illusion and all kinds of distortions play into it. You can read about diffraction effects off speaker edges and room furniture and reflections off the walls as well as Xover lobing etc. playing a lot more role in the subjective perception than the naked driver distortion on a pure tone being 30 or 40dB down. In reproduction just as in the recording process all means are allowed to arrive at whatever the subject listener considers pleasing. It is all entertainment. I do not even hope to have the hearing equivalent to that of a mixing engineer who put "the target signal for reproduction" together. I could not even care less whether he was able to hear something better or worse than myself because I will tweak the sound any way possible to arrive at something that pleases me in a given place on a given day with a given program material until I have decided that even that should change. So now back to your curves. When you get tired of looking at those:
The Art of Listening Film
Geddes on Distortion perception
btw the low order distortion being pleasing is also evident in First Watt amp designs by Pass.
I keep getting a reference to "reproduction": What are you exactly trying to reproduce? there is no even a standard in the recording industry to begin with, for microphone placement, room treatment or equipment used; not to mention sound mixing and EQing by a random individual.
And how are you to reproduce sound coming from different sources physically apart by playing it all out of say two speakers in a different room? the whole "stereo reproduction" etc is an illusion and all kinds of distortions play into it. You can read about diffraction effects off speaker edges and room furniture and reflections off the walls as well as Xover lobing etc. playing a lot more role in the subjective perception than the naked driver distortion on a pure tone being 30 or 40dB down. In reproduction just as in the recording process all means are allowed to arrive at whatever the subject listener considers pleasing. It is all entertainment. I do not even hope to have the hearing equivalent to that of a mixing engineer who put "the target signal for reproduction" together. I could not even care less whether he was able to hear something better or worse than myself because I will tweak the sound any way possible to arrive at something that pleases me in a given place on a given day with a given program material until I have decided that even that should change. So now back to your curves. When you get tired of looking at those:
The Art of Listening Film
wow I guess we should ALL stop what we're doing in the DIY audio world because we don't have PhD level knowledge on the subject! Sure glad you stopped by to enlighten us all, because if not, I would have kept on going and having FUN in this HOBBY that I can afford. Jeez, what a debbie downer. So what if we're wrong? We are not a cult that is forcing others to follow our ways, everyone can do as they please. I, for one, will keep on playing with these speakers (and probably a few more) in this FUN HOBBY of mine. And since it's my hard earned money, it should not play a factor at all in your life.