Micke,
not bothering with its devious title, the amp will joyfully operate in push-pull mode and will refuse to produce a transparent single-ended sound. Fortunately, all the supply caps remain right in the signal path in order to make some profit. On the other hand, power supply ripple suddenly is much less of a problem, some of it will be "canceled" along with parts of the signal.
not bothering with its devious title, the amp will joyfully operate in push-pull mode and will refuse to produce a transparent single-ended sound. Fortunately, all the supply caps remain right in the signal path in order to make some profit. On the other hand, power supply ripple suddenly is much less of a problem, some of it will be "canceled" along with parts of the signal.
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Wuyit..
I wonder why your attitude is like this..??
I pose ideas.. they may not be the best or particular well thought out..but never the less they are ideas that holds pros an cons...You shoot it down just by throwing out statements...not in anyway fruitfull and does not encourage people to post ideas for all to share and learn from...There may be a number of good reasons why my idea will not work...but signal modulation of the PSU Caps is not one of them...
A reason could be...that the two strings are not so identical that a good summation is possible..But that I don't know and is for sure an area to explore....another is the transformer used.. there may be other and better ways to phase-shift the signal to the second string....And. And. And..list is long...and will probably only be answered by actually building the beast...
I wonder why your attitude is like this..??
I pose ideas.. they may not be the best or particular well thought out..but never the less they are ideas that holds pros an cons...You shoot it down just by throwing out statements...not in anyway fruitfull and does not encourage people to post ideas for all to share and learn from...There may be a number of good reasons why my idea will not work...but signal modulation of the PSU Caps is not one of them...
A reason could be...that the two strings are not so identical that a good summation is possible..But that I don't know and is for sure an area to explore....another is the transformer used.. there may be other and better ways to phase-shift the signal to the second string....And. And. And..list is long...and will probably only be answered by actually building the beast...
Miib,
compare your SEPP to a valve/tube output stage.
In valve parlance they call that Push Pull.
A single device or a parallel set of singles devices is called Single Ended.
You have shown a pair of Nch devices driven opposite phase to give PP topology.
compare your SEPP to a valve/tube output stage.
In valve parlance they call that Push Pull.
A single device or a parallel set of singles devices is called Single Ended.
You have shown a pair of Nch devices driven opposite phase to give PP topology.
Hi Andrew.....SEPP= Single ended Push pull...
That is what it is.. two strings driving the load push-pull, each string swinging the full signal in a single-ended manner....
Takes the need for the coupling cap out, but introduces other set of problems..question is which is the lest compromise...??
That is what it is.. two strings driving the load push-pull, each string swinging the full signal in a single-ended manner....
Takes the need for the coupling cap out, but introduces other set of problems..question is which is the lest compromise...??
MiiB,
I`m sincerely sorry, it was not my intention to dispirit you and to berate your ideas, however, making a differentiation between push-pull and single-ended would almost certainly benefit you. You have posed these questions before in three different threads and I answered. The answers can be wrong, but hypothetically, anyway, may contain some truth.
Transformers are far from ideal devices, their sonic impact is worse than that of electrolytic capacitors that you want to avoid at all costs.
It is possible to achieve very nice sound with balanced topologies, and they offer many practical advantages over the single-ended topology.
I`m sincerely sorry, it was not my intention to dispirit you and to berate your ideas, however, making a differentiation between push-pull and single-ended would almost certainly benefit you. You have posed these questions before in three different threads and I answered. The answers can be wrong, but hypothetically, anyway, may contain some truth.
Transformers are far from ideal devices, their sonic impact is worse than that of electrolytic capacitors that you want to avoid at all costs.
It is possible to achieve very nice sound with balanced topologies, and they offer many practical advantages over the single-ended topology.
I would add that if you really want transparency (1) you'd avoid SE as the plague. 😉
(1) transparent in the sense that nothing is added and nothing is taken away from the signal.
jan didden
Jan,
the significance of transparency? Most importantly an ear-friendly harmonic distribution and accuracy in time.
the significance of transparency? Most importantly an ear-friendly harmonic distribution and accuracy in time.
I like your "two-string" design. It should be better than the design at the start of the thread because even-harmonic distortion will be canceled. I'm not sure, but I suspect odd-order distortion may be lower than with a normal bridged push-pull class A amp too.
Some will love the transformer and some will hate it, but that's not important. Those who don't like transformers can simply replace it with a valve phase-splitter or something else.
For smaller signals with currents of +-1A there seems to be no distortion at all..it simply cancels everything...but simulation is just simulation...for larger signals approacing current limit the 3. order starts to grow
The transformer was a dirty way the get the proper biasing.. and at the same time phase shift the signal
I think it must be built to see how it performs...There so many things i can't figure out....
how low is the output impedance...??
Will it DC drift..??
Here it swings +-4A...and can have a voltage swing of app 35 V..with a consumption of app 300W/one channel (One heck of at hottie)
The transformer was a dirty way the get the proper biasing.. and at the same time phase shift the signal
I think it must be built to see how it performs...There so many things i can't figure out....
how low is the output impedance...??
Will it DC drift..??
Here it swings +-4A...and can have a voltage swing of app 35 V..with a consumption of app 300W/one channel (One heck of at hottie)
I think SEPP refers to another topology. This amplifier
has often been called "balanced single-ended", a phrase
I first saw used by Bel Canto describing one of their
amplifiers.
😎
Thanks....Who better than you to clearify....🙂
Still the balanced single ended is a pure approach...(BSE...better than BS) albeit not so so effective...
Can you tell a little about output impedance...?? As I cant figure out how to measure it....
I'll try to evolve the concept a little....
Still the balanced single ended is a pure approach...(BSE...better than BS) albeit not so so effective...
Can you tell a little about output impedance...?? As I cant figure out how to measure it....
I'll try to evolve the concept a little....
apply a test curent source across the load terminals - the voltage change divided by the current is the impedance
in LTspice this can display the .AC analysis plot in Ohms with a phase - use current source AC = 1 A even if the circuit wouldn't handle 1 A - spice linearizes the circuit and isn't really "simulating" in .AC analysis, just plugging the frequency sweep into the Laplace small signal linear model at the operating point
need a good transformer model to capture its bandwidth limitations
in LTspice this can display the .AC analysis plot in Ohms with a phase - use current source AC = 1 A even if the circuit wouldn't handle 1 A - spice linearizes the circuit and isn't really "simulating" in .AC analysis, just plugging the frequency sweep into the Laplace small signal linear model at the operating point
need a good transformer model to capture its bandwidth limitations
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Thanks....LT has many capabilities...just need to find its screws...
and for sure....the transformer model needs to be built to perfection....problem is that magnetics and coils in reality is far from is perfection...quite sure that a mosfet or tube based splitter will be the better solution...
Have some ideas in mind...🙂
and for sure....the transformer model needs to be built to perfection....problem is that magnetics and coils in reality is far from is perfection...quite sure that a mosfet or tube based splitter will be the better solution...
Have some ideas in mind...🙂
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Hi Nelson,
push-pull signifies balanced operation, devices operating in phase opposition, where the signal is balanced to ground and is symmetric with reference to ground. Single-ended signifies unbalanced signal handling, where the signal is referred to ground and is asymmetric with reference to ground. There`s nothing in between, a crossbreeding is not possible. The key issue is conduction angle. Alternating transmission (regardless of designation) implies substantially increased distortion compared to full-cycle conduction.
push-pull signifies balanced operation, devices operating in phase opposition, where the signal is balanced to ground and is symmetric with reference to ground. Single-ended signifies unbalanced signal handling, where the signal is referred to ground and is asymmetric with reference to ground. There`s nothing in between, a crossbreeding is not possible. The key issue is conduction angle. Alternating transmission (regardless of designation) implies substantially increased distortion compared to full-cycle conduction.
It's then it's one of the few family of beasts where cross breading is not possible....🙂
Fundamental religion may be the most obvious where multifaceted and nuanced points of views are not accepted...
I believe the name or "nickname" refers the the way balanced operation is achieved...just to put some words behind or around the structure of things...so many different ways to achieve or to have balanced operation..
I mean were all humans...but still we can attach some types to that... Swedish, Danish, tall, clever, stupid..and ..and....adverbs are just used to give more information about what it's is were talking about.
Fundamental religion may be the most obvious where multifaceted and nuanced points of views are not accepted...
I believe the name or "nickname" refers the the way balanced operation is achieved...just to put some words behind or around the structure of things...so many different ways to achieve or to have balanced operation..
I mean were all humans...but still we can attach some types to that... Swedish, Danish, tall, clever, stupid..and ..and....adverbs are just used to give more information about what it's is were talking about.
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I think it's more subtle than that. I always understood it like this:
If you say that SE is a single device with a passive load that drives a ground referenced load, that's SE unbalanced. If you then take another of these, drive it in opposite phase and hang the load between the two, that's SE-balanced.
A push-pull stage is a stage where both devices, one on top of the other, are driven and if you then load it to ground that's a SE push-pull. Again, if you take two of those and drive them in opposite phases and hang the load between them, then that's balanced push-pull, no?
jan didden
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