Does that mean the expensive ones can read your mind, or have the "psychic" means to eyeball your prototype ..
?Frank
Does that mean the expensive ones can read your mind, or have the "psychic" means to eyeball your prototype ..
Do you mean that Special SIM for cables and vacuum rectifiers that draws break-in curves?
Yes, continue here. You said:
And the first part I agree with. Ground loop path variations will effect the system to some degree, and may subjectively alter the sound quality. I have gone through many iterations of dealing with such matters, can't say I always have a firm handle on what works and what doesn't, but understand the potential impact.
However, what I was responding to was your stating that the change wasn't due to material properties. I have done tweaking for many years where the electrical layout has not changed in the conventional sense, including loop pickup and have still seen the effects. In one sense anytime anything is moved, even at the most minute level, loop pickup will alter but the difference between a good vs. a less good arrangement is too dramatic for changes in flux to be the cause in what I've experienced.
Frank
haha. Almost -- they can calculate the trace parameters and pcb material (or substrate) and include all the trace factors amoungst other things - like thermal gradients and emi and for RF - the S parameters and much more. Even suggest best routes for path lengths and Z and timing events, delays and on and on. Not LT free software being used here. Why Scott W. says his company has spent millions on their SIM's. Thus, can do a complete design and be sure it will work without issues and go right to fab.Does that mean the expensive ones can read your mind, or have the "psychic" means to eyeball your prototype ..
Frank
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Impressive! But, do they use such for their evaluation boards? And, could a completely human designed and constructed PCB be effectively scanned and analysed? Or would the effort to input such make it not worthwhile?
Frank
Adding a virtual music source and a virtual listener, real music will be restored to humans, while SIMs programs will fight endless on DIY forums about electronic performances....
To be serious, while SIMs programs do not change anything to the process they fast and simplify, i wonder if the loss of contact with calculations during design, and real parts during prototype, as well as the oscilloscope witch is some king of prolongation of ourself, will not finish by cutting us away from a physical knowledge, something incarnated we acquire with time.
You know, the "Add-it, it sound better, remove-it, it sound better".
Thank-you for not observing that it is typically an old fart questioning.
You know, the "Add-it, it sound better, remove-it, it sound better".
Thank-you for not observing that it is typically an old fart questioning.
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I am absolutely agree with you. It is easy to calibrate own perception and learn to think in terms of schematics, "feel" and "hear" distortions imagining waveforms, spectrums, when working with breadboards, tools, soldering iron. But how somebody would expect to design something really new using computer models only? It's like building a "poetry" by copying and pasting from schoolbooks and dictionaries. Dull and boring.
Thank you SY for the answer (and I'll stick to linear systems).
So any acoustic resonances (room and speaker enclosure 3D space) are non equalizable.
Effects from structure vibrations (e.g. driver or enclosure, if not damped) are non equalizable.
Effects from cone break-up are non equalizable.
I wonder if there can exist an acoustic or mechanical resonance that is not plagued by your last sentense.
George
Ya know...it kinda does, doesn't it??
Buuuut...I have experimental evidence...he does not..
jn
I meant it well. I respect this man.
When he was theorizing the capacitor as a transmission line, he already had some real life indications while with Motorola. Later it seems he had some proof with the fabrication of high speed digital stuff.
And then it was you with that post
George
George, I would not look at this things in black/white theoretical light. We can't avoid resonances, but we can damp them mechanically, then clean the rest by EQ. The question is, "In which place to assume the waist", the problem is quite fatty and does not have some obvious optimal solution.
Hi gpapag, sy, all
When you move from circuits to acoustics, you enter a new domain where “it depends”.
Take cone resonance, that is a resonant system between the motor and radiator in the equivalent circuit. Lets say the response curve looks nice up to say 3KHz where it mounds to a peak of say +10dB over the average level.
You can use a steep or brickwall crossover or eq the response and to first order, one has “fixes” the problem of the excess gain from the mechanical resonance and it’s fixed in magnitude and phase. On the other hand, that mechanical gain is still present and although the response can be flattened, you cannot get rid of the magnification of the motors natural distortion at sub-multiples of the resonant peak. For example, that +10dB gain at 3KHz, will magnify the 3rd harmonic at 1KHz by +10dB also as well as harmonics at other lower frequencies.
In a room, you usually have a mixture of minimum and non minimum phase conditions. The old rule of thumb was only cut peaks and the logic was the following. When you have a deep notch in the response, you have a “cancelation notch” which is (in a room) usually caused by the direct sound combing with a delayed version of the same signal. If you boost the notch, you are adding energy to the source and the canceling signal BOTH, a non-minimum phase condition.
If you measure speakers, you may have seen a notch in the upper bass, a cancelation notch resulting from the direct path signal mixing with the floor bounce signal, the lowest notch frequency, is where the path length difference is 180 degrees. You can’t add enough boost at that frequency to fix it and any you add also applies a phase correct which isn’t appropriate. EQ is a double edged sword.
Best
Tom Danley
When you move from circuits to acoustics, you enter a new domain where “it depends”.
Take cone resonance, that is a resonant system between the motor and radiator in the equivalent circuit. Lets say the response curve looks nice up to say 3KHz where it mounds to a peak of say +10dB over the average level.
You can use a steep or brickwall crossover or eq the response and to first order, one has “fixes” the problem of the excess gain from the mechanical resonance and it’s fixed in magnitude and phase. On the other hand, that mechanical gain is still present and although the response can be flattened, you cannot get rid of the magnification of the motors natural distortion at sub-multiples of the resonant peak. For example, that +10dB gain at 3KHz, will magnify the 3rd harmonic at 1KHz by +10dB also as well as harmonics at other lower frequencies.
In a room, you usually have a mixture of minimum and non minimum phase conditions. The old rule of thumb was only cut peaks and the logic was the following. When you have a deep notch in the response, you have a “cancelation notch” which is (in a room) usually caused by the direct sound combing with a delayed version of the same signal. If you boost the notch, you are adding energy to the source and the canceling signal BOTH, a non-minimum phase condition.
If you measure speakers, you may have seen a notch in the upper bass, a cancelation notch resulting from the direct path signal mixing with the floor bounce signal, the lowest notch frequency, is where the path length difference is 180 degrees. You can’t add enough boost at that frequency to fix it and any you add also applies a phase correct which isn’t appropriate. EQ is a double edged sword.
Best
Tom Danley
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