Surely there comes a point where some kind of chastising is necessary when someone repeatedly and knowingly attempts to derail a thread with false information?
I can't catch why some people are very active sometimes, even if they are wrong for everybody except themselves. Maybe, they believe that activity = truth. Sometime it works.
That is the big question, Raj;"knowingly". We assume that ought to be so, but it apparently is not. I'm no psychologist but this is not average self-aware behaviour.
Andrew T (quote)
I cannot understand what Wuyit is defining........
I think you may be just a tad disingenuous there, with a blatant oxymoron too! 🙄
I'll wager there is more than one audio electronics book or WiKipedia link within reach that you can find better definitions than any
off-the-cuff forum quote. If not, Amazon UK will be more than happy to lighten your wallet. They cleaned me out, anyway! 😀
I think I know what my personal definitions are for SE & PP.
But this thread got bogged down in argument and most of that stalling was due to us having different definitions.
I was hoping to bring some clarity to the discussions by agreeing definitions for SE & PP so that the discussion can be taken forward.
I will go and find out what the dictionary has to say about "oxymoron".
I think I already know "disingenuous". I disagree with your assertion, not even with "tad" applied.
But this thread got bogged down in argument and most of that stalling was due to us having different definitions.
I was hoping to bring some clarity to the discussions by agreeing definitions for SE & PP so that the discussion can be taken forward.
I will go and find out what the dictionary has to say about "oxymoron".
I think I already know "disingenuous". I disagree with your assertion, not even with "tad" applied.
Hi,
if you don´t know, why say it`s wrong, if you do know, why not say what´s wrong? Strange, very strange...
Calling the opposite phase signals “single-ended” won`t change their properties and the transfer function that is different to that of a single-ended, no matter if one input is 0 V like a single-ended signal.
if you don´t know, why say it`s wrong, if you do know, why not say what´s wrong? Strange, very strange...
Calling the opposite phase signals “single-ended” won`t change their properties and the transfer function that is different to that of a single-ended, no matter if one input is 0 V like a single-ended signal.
Andrew,
please present your personal definition of balanced and single-ended to establish a necessary bases for comparison.
please present your personal definition of balanced and single-ended to establish a necessary bases for comparison.
I believe....and this is strictly on me....
signals can be either single ended or balanced..(push pull) this can happen in various stages of the chain...
If you look at the output of an amplifier most amplifiers are single ended simply because they are driving the load by one end and with at reference to GND. So from the speakers point (speaker-terminal and out) of view most amplifiers are single ended...
If you then look inside the amplifier and look at the signals most amplifier operate with differential signals...where they treat each side of the signal with separate devices..these amplifiers operate internally in push pull...and by that they reach a better efficiency...they have differential or quasi differential output.. but still they drive the load single ended....
Then there is amplifiers like the 99 power follower, Vladimir's take on it or The Pass Aleph.. where the waveform is never split and where the signal is kept single ended through out the amplifier.. these only Run in Class A and are low in efficiency and current limited, but for sure they are pure in approach and can have very high quality sound vise...(though distortion may be higher)
Then there are balanced designs where the load is basically driven by two amplifiers one pushing and one pulling...this can also be done in many ways...and by many amplifier topologies....I think this fueled some opinions about a name for such a configuration where two single ended amplifiers was diving a load between them...Pass Called it Balanced single ended....
I think the confusion here is based on how do amplifiers operate or what does the load see.....which is not the same...
signals can be either single ended or balanced..(push pull) this can happen in various stages of the chain...
If you look at the output of an amplifier most amplifiers are single ended simply because they are driving the load by one end and with at reference to GND. So from the speakers point (speaker-terminal and out) of view most amplifiers are single ended...
If you then look inside the amplifier and look at the signals most amplifier operate with differential signals...where they treat each side of the signal with separate devices..these amplifiers operate internally in push pull...and by that they reach a better efficiency...they have differential or quasi differential output.. but still they drive the load single ended....
Then there is amplifiers like the 99 power follower, Vladimir's take on it or The Pass Aleph.. where the waveform is never split and where the signal is kept single ended through out the amplifier.. these only Run in Class A and are low in efficiency and current limited, but for sure they are pure in approach and can have very high quality sound vise...(though distortion may be higher)
Then there are balanced designs where the load is basically driven by two amplifiers one pushing and one pulling...this can also be done in many ways...and by many amplifier topologies....I think this fueled some opinions about a name for such a configuration where two single ended amplifiers was diving a load between them...Pass Called it Balanced single ended....
I think the confusion here is based on how do amplifiers operate or what does the load see.....which is not the same...
First I think theres a problem with calling PP and SE amps balanced or unbalanced, these are 2 different things. If you wanted you could design either PP or SE amps with internal signals that are mostly if not completely balanced or not.
Not really. Most amps (like the blameless topology) take an unbalanced input (or a balanced in and immediately convert it to unbalanced) and keep it unbalanced right to the output for class A or where it is split into +ve and -ve components for class B at the oP stage. (this splitting is not balancing the signal more of a half wave rectification)
Not really. Most amps (like the blameless topology) take an unbalanced input (or a balanced in and immediately convert it to unbalanced) and keep it unbalanced right to the output for class A or where it is split into +ve and -ve components for class B at the oP stage. (this splitting is not balancing the signal more of a half wave rectification)
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Aside from the well examined basis of circuit operation
the major theme I also found was certainly......troll
Hi,
blue line = sine wave representing odd symmetry
red line = cosine wave representing even symmetry
It`s fundamentally about symmetry and time.
It´s hard to comprehend the inner nature of things from explanations, where terms like "eliminate", "reject" and "cancel" are used to describe physical processes. You can possibly cancel your wedding or air flight, but in physics, nothing can be eliminated, rejected or canceled. Likewise, once arisen, distortions will stay in the system. Conversion is a possibility, though, at the price of higher complex distortion; now, you may like the sound better that way, but that´s not a subject to discussion.
The symmetry of the output signal waveform reflects its harmonic content as a consequence of function symmetry f(x), which is an important nonlinearity measure. By an odd function f(x), points of even symmetry in the input waveform become points of odd symmetry in the output waveform. In other words, an odd function f(x) converts symmetric input waves into asymmetric output waves resulting in an absence of even order harmonics. It´s exactly what balanced topologies do, obviously originated in the two-input / two-phase operation, causing the time error.
Tubes really shine in this regard (as well), displaying a nearly ideal function f(x), (only in single-ended mode), due to a small time difference between input and output (and a fast response to a change in the signal), giving a peerless sound stage. Despite of that, the impairment effects of balanced operation are unmistakable.
So it is pure trigonometry, not depending on device technology.
blue line = sine wave representing odd symmetry
red line = cosine wave representing even symmetry
It`s fundamentally about symmetry and time.
It´s hard to comprehend the inner nature of things from explanations, where terms like "eliminate", "reject" and "cancel" are used to describe physical processes. You can possibly cancel your wedding or air flight, but in physics, nothing can be eliminated, rejected or canceled. Likewise, once arisen, distortions will stay in the system. Conversion is a possibility, though, at the price of higher complex distortion; now, you may like the sound better that way, but that´s not a subject to discussion.
The symmetry of the output signal waveform reflects its harmonic content as a consequence of function symmetry f(x), which is an important nonlinearity measure. By an odd function f(x), points of even symmetry in the input waveform become points of odd symmetry in the output waveform. In other words, an odd function f(x) converts symmetric input waves into asymmetric output waves resulting in an absence of even order harmonics. It´s exactly what balanced topologies do, obviously originated in the two-input / two-phase operation, causing the time error.
Tubes really shine in this regard (as well), displaying a nearly ideal function f(x), (only in single-ended mode), due to a small time difference between input and output (and a fast response to a change in the signal), giving a peerless sound stage. Despite of that, the impairment effects of balanced operation are unmistakable.
So it is pure trigonometry, not depending on device technology.
Attachments
I think WuYit says that when you start using any kind of symmetry or feedback to lower distortion or non linearities you just switch the problem to a higher order..as theres no such thing as perfect cancellation...
He is fundamentally wrong and he doen't understand feedback.
If you have a 1V 1kHz sine and partially cancel it with a 0.9V 1kHz sine you still have nothing more than a 1kHz sine.
It always pays to think for yourself 😉
jan
I do try think for myself 🙂 But at the same token i try to understand the thinking of others...
I agree.... on that with the 1 KHz sine wave feedback, but is the sine wave you try to cancel really the same or are the two time shifted just a fraction....??
I agree.... on that with the 1 KHz sine wave feedback, but is the sine wave you try to cancel really the same or are the two time shifted just a fraction....??
I don't know...guess that's the big question....and for sure not easy to give a good good answer to....
For sure if the sine wave is time shifted the resulting waveform will be distorted...
Is massive amounts of feed back good...??
Is there difference on local and global feed back...??
For sure if the sine wave is time shifted the resulting waveform will be distorted...
Is massive amounts of feed back good...??
Is there difference on local and global feed back...??
Nope... Misconception....Time shift will not alter the wave form......Tried to subtract two sines with 10 degrees time shift in LT-spice.. looked at the resulting waveform.. Still a sine No distortion (at -240 DdB's)
hmmm
hmmm
Andrew,
Of course, it would be desirable and possible to describe things (even) more correctly and clearly.
The mathematical function f(x) can have even, odd or neither even nor odd symmetry with respect to the y-axis. A mathematical function is the very best way to express and explain device transfer function linearity, or in this case, to show a difference between the single-ended and balanced function.
Of course, it would be desirable and possible to describe things (even) more correctly and clearly.
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