Joachim,
Of course I listen. This goes without saying.
I have listened to many speakers that measured spectacularly worse than they sounded and to others that sounded bad, even though they measured near perfect. So I always consider measurements in the context of listening as well.
Ciao T
Of course I listen. This goes without saying.
I have listened to many speakers that measured spectacularly worse than they sounded and to others that sounded bad, even though they measured near perfect. So I always consider measurements in the context of listening as well.
Ciao T
Joachim, I think I have a good feeling about what your priorities are. Look forward to your results.
As far as measurements are concerned, I tend to cycle through measurements, modification, and listening. Sort of like a DOD development life cycle thing.
As far as measurements are concerned, I tend to cycle through measurements, modification, and listening. Sort of like a DOD development life cycle thing.
Personally, the way I consider equalization is speaker first, room after. It make sense to keep those separate unless the speakers are going to be used in one room until they die.
Thorsten, i see one reason that some speakers sound good although they measure "bad" that since MLSSA came not much measurements are being made concerning distorton and dynamic behaviour. The analysys is restricted to frequency and phase response and of cause the all mighty and beautifull CSD. I find dynamics and low distortion important for good reproduction as well. Going into dynamic measurements reveil a lot to be desired and the Klippel Analyser gives us a new tool but a typical DIY´er can not afford this. Add to this the discussion about DI plus linear phase and efficiency and you see that some measurements done on axis in the frequency domain may tell us very little.
I consider equalization is speaker first, room after
I like that phrase, what we try is going from 2 dimensional to 3 dimensional. Ones the sound has left the membranes, not much more can be done at the moment.
I like that phrase, what we try is going from 2 dimensional to 3 dimensional. Ones the sound has left the membranes, not much more can be done at the moment.
I really wish more factories would publish Klippel based data, including scanner data. But you are right about sound leaving the membranes. I think Thorsten's approach of measuring multiple points is a good one. If we get reasonable performance over a range of points, then we equalize and take out some stored energy, the result should be very good. I value the Kippel analyzer, and always refer to the data when selecting drivers. Also hope to be able to linearize electronically one day.
As for the room. Since it's different from case to case, it's going to really be almost impossible to perfect it without some tradeoffs in some other aspects. It then becomes an art as to how to do the tradeoff.
As for the room. Since it's different from case to case, it's going to really be almost impossible to perfect it without some tradeoffs in some other aspects. It then becomes an art as to how to do the tradeoff.
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I've started to play some more CDs through the equalized setup. What is interesting is the CDs that I originally considered reversed polarity now sound correct without reversing the polarity. This is very strange. I will study this a bit more and see what the difference really is.
Klippel data is more for companies that develop drivers. The only company i exchange Klippel data with is SEAS. Especially the Danish companies refuse to use the Klippel. They have their own methods. But it is very popular in Italy and China. Klippel works on actively lowering distortion in drivers for 30 years but to my knowlage there is no system on the market yet that does that. Theoretically it is posible to synthesize dynamic driver parameters but as far i understand Prof. Klippel it is more interesting for really small speakers like used in cell phones and computers. I had one of Klippels PHD´s in my home and when he listened to my system he admitted that subjectively distortion in the speakers i played for him was already so low that not much more can be done. I worked also with Bill Waslo of Liberty Instrument on distortion isolation. The Praxis software can separate the linear and unlinear part of a loudspeaker. Ones saparated we can mix in the distortion into an undistorted music signal over headphones. Again i could hear no diffence if the distortion is mixed in or not provided the speakers are of "good" quality and not driven into overload. What could be heard stronly though was the contribution of the room that the distortion separation process correctly identified as "distortion". Sorry to say soongsc, do not expect a miracle. Have being there, done it.
On the audibility of phase distortion the Essex system allowed direct comparion of the speaker being Linkwith 4th order and the phase linear variant of it. Frequency response, distortion and DI could be held constant and only the phase correction could be enganged or not. With artificial signals like a short impulse we could here differences. It sounded "tick" with the linear phase and "tock" without. With music is was much more difficult to differentiate, especially with complex material like a full blown clasical ensemble. One listener though claimed that he could hear " better focus and 3 dimensionality " when the phase correction was engaged. In a blind experiment though made with 20 people consisting of my workforce and the experimenters the diffence was lost. That does not mean that linear phase is not a good goal to go for. It just means that it is a secondary effect that is easily swapped by frequency deviations, DI, distortion and dynamics. These things have to be solved first and then we can start to tacle phase. Why you got that result with oposite phase being wrong and then right i can not say with 100 % confidence. I for one had the subjective impression that the phase linear version was a bit easier on the ear so you may have gotten some kind of hardness first without equlisation that went away after equalisation.
On the audibility of phase distortion the Essex system allowed direct comparion of the speaker being Linkwith 4th order and the phase linear variant of it. Frequency response, distortion and DI could be held constant and only the phase correction could be enganged or not. With artificial signals like a short impulse we could here differences. It sounded "tick" with the linear phase and "tock" without. With music is was much more difficult to differentiate, especially with complex material like a full blown clasical ensemble. One listener though claimed that he could hear " better focus and 3 dimensionality " when the phase correction was engaged. In a blind experiment though made with 20 people consisting of my workforce and the experimenters the diffence was lost. That does not mean that linear phase is not a good goal to go for. It just means that it is a secondary effect that is easily swapped by frequency deviations, DI, distortion and dynamics. These things have to be solved first and then we can start to tacle phase. Why you got that result with oposite phase being wrong and then right i can not say with 100 % confidence. I for one had the subjective impression that the phase linear version was a bit easier on the ear so you may have gotten some kind of hardness first without equlisation that went away after equalisation.
I would never use headpones as reference for subjective evaluation unless I have seen data related with stored energy with headphones in the listening position. Most mistakes people make in subjective listeing is that there is insufficient information and prerequisit requirements of the systems used to conduct such evaluation. Therefore, when differences cannot be heard, you really cannot determine exactly why, and just blindly attribute it as being "not audible", which is true for that particular setup, but cannot be applied universally. If distortion levels are below stored energy levels, of course we cannot hear it. But I have not seen any report that addresses this. The polarity issue is an interesting one. I once asked a group of mic builders how they determine exactly what polarity the music is recorded in, and it raised some confusion; however, I have demonstrated to different people on thier own systems, and at least 80% learned what a difference it made. 90% of the time I can just listening for less than a minute to determine whether the music is not in the right polarity, and improves significantly when swapped correctly.
Personally, I think it's up to the designer to first be able to hear what others are talking about. At least I have learned from many audiophiles, and their views have been very valuable. Normally, I never setup a test to test the person listening. You only get a yes or no, but not more valuable information freely expressed by the listener through dialog. I value the intelligence of the listeners.
Not so long ago, I was trying to decide which interconnect to finalize as our first product. One sounded very transparant, and one sounded very seducing and emotional. It was a hard decision, and different people had different opinions. Finally the decision was to go "as transparant as possible".
I personally think driver manufacturers should publish enough information to help people decide what driver is more suitable for design purpose. For example, when designing small speakers, if over excursion characteristics change gradually, it is more favorable, whereas, for large systems, when you know what maximum SPL you are designing for, it's necessary to tradeoff whether you want VERY linear up to the limit but are willing to accept abrupt onset of distortion or whether you still want gradual onset of distortion up to the maximum SPL to avoid abrupt change due to over excursion.
Personally, I think it's up to the designer to first be able to hear what others are talking about. At least I have learned from many audiophiles, and their views have been very valuable. Normally, I never setup a test to test the person listening. You only get a yes or no, but not more valuable information freely expressed by the listener through dialog. I value the intelligence of the listeners.
Not so long ago, I was trying to decide which interconnect to finalize as our first product. One sounded very transparant, and one sounded very seducing and emotional. It was a hard decision, and different people had different opinions. Finally the decision was to go "as transparant as possible".
I personally think driver manufacturers should publish enough information to help people decide what driver is more suitable for design purpose. For example, when designing small speakers, if over excursion characteristics change gradually, it is more favorable, whereas, for large systems, when you know what maximum SPL you are designing for, it's necessary to tradeoff whether you want VERY linear up to the limit but are willing to accept abrupt onset of distortion or whether you still want gradual onset of distortion up to the maximum SPL to avoid abrupt change due to over excursion.
To my knowlage there was even a book published about the audibility of absoute phase.
It was called "The Wood Effect".
How the "Distortion Isolation in the Time Domain" works in the Praxis software is not easy to explain. The undistorted music you hear has the transfer function of the speaker overlaid, energy storage and all. It only seperates the "unlinear part" like harmonic distortion, intermodulation and rubb and buzz. I think listening to a good headphone to this distortion works. It does NOT separate energy storage. I whould say the less the better but how much is audible i can not say.
I had another comunication with Mr.Stoll and although he agreed that the phase distortion of a L-R 4th order crossover is not easyly heard at a medium crossover point, phase dsitortion is very audible in the bass due to his experience and he uses "heavy DSP" to correct the time delay in the bass down to very low subsonic frequencies. I think he talked about down to 6Hz.
It was called "The Wood Effect".
How the "Distortion Isolation in the Time Domain" works in the Praxis software is not easy to explain. The undistorted music you hear has the transfer function of the speaker overlaid, energy storage and all. It only seperates the "unlinear part" like harmonic distortion, intermodulation and rubb and buzz. I think listening to a good headphone to this distortion works. It does NOT separate energy storage. I whould say the less the better but how much is audible i can not say.
I had another comunication with Mr.Stoll and although he agreed that the phase distortion of a L-R 4th order crossover is not easyly heard at a medium crossover point, phase dsitortion is very audible in the bass due to his experience and he uses "heavy DSP" to correct the time delay in the bass down to very low subsonic frequencies. I think he talked about down to 6Hz.
Looking at the levels of stored energy, it certainly will have more masking effect making the audibility of other types of distortion less probable to detect was my main point. The less stored energy you have, the more audible other types of distortion will be. Since earphones/headphones are bound to interact with the ear to for some stored energy not existing without, some distortion is going to be masked.
Normally if no polarity switch is available, the just swap the + and - connectors at the amplifier output for all speakers.
You know that this will change a multitude of other variables that are "highly important" to the average audiophool. Funny text: SoundStage! Max dB - Audio Signal Polarity - A Look Behind the Curtain (10/1999)
ah, now I know why my friend's system sounds crappy. He disregarded the little arrows on his speaker cables for in and out. I also believe he uses non-polar caps but mounted with the label upside down. This cannot be right ! 😀
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Until I saw the date (October), I thought it was an April Fool's joke. Was this meant as parody?
It's well known that in reality, devices do not operate in perfect symmetry. Whether this causes audible difference or not remains to be investigated. However, in the process of studying how to improve audio reproduction. My criteria is just let people listen on their own systems. If they hear the difference, fine, if not, also fine. People with a closed minds just isolate themselves from whatever progress until everyone else agree. We need people like that too.😀
""You know that this will change a multitude of other variables that are "highly important" to the average audiophool.""
Remember when DIY audio was fun and participants were tolerant of the views of others, even when those views didn't agree with their own? Remember those grand old days when participants showed respect for each other and didn't call other participants derogatory names because they had a different point of view from their own? 'Member that?
Remember when DIY audio was fun and participants were tolerant of the views of others, even when those views didn't agree with their own? Remember those grand old days when participants showed respect for each other and didn't call other participants derogatory names because they had a different point of view from their own? 'Member that?
Nobody needs close-minded people but those that make claims have the burden of proof. And they should prove it in a way that is repeatable (for others). But yes, I'd agree that some people already have closed their minds.
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