Hi ! in a very interesting article by Mr Pass describing is project called the Zen amplifier
https://www.passdiy.com/project/amplifiers/the-zen-amplifier
i was struck by this passage
I have also read that output pairs made of two same npns given their nature could sound more push than pull and in this way behave more like a single ended amp ?
I would try the single ended approach at least for preamp The only drawback mentioned is a good amount of 2nd order distortion ?
Interesting topic indeed What do you think ?
https://www.passdiy.com/project/amplifiers/the-zen-amplifier
i was struck by this passage
it seems to me that this position has solid bases. For instance a good compromise could a single ended front end followed by a push pull amp for convenience
I have also read that output pairs made of two same npns given their nature could sound more push than pull and in this way behave more like a single ended amp ?
I would try the single ended approach at least for preamp The only drawback mentioned is a good amount of 2nd order distortion ?
Interesting topic indeed What do you think ?
On the other hand, the ear is biased at the ambient pressure and will push and pull.
Hi yes you are right There would be a very simple test to assess the real situation
To go to a concert with a pressure meter and record the variations of the air pressure at the listening point during the concert
i do not know if there are measurement devices able to measure both positive and negative pressures If not two devices are needed
To go to a concert with a pressure meter and record the variations of the air pressure at the listening point during the concert
i do not know if there are measurement devices able to measure both positive and negative pressures If not two devices are needed
I believe that's called a microphone. If you consider how a "piston-phone" type microphone calibrator works, it's actually a motor, crankshaft and piston like a car engine. So when you stick the microphone in the device, it's actually pushing and pulling a known pressure against the microphone diaphragm. The level of alternating pressure translates to a real-world SPL, as in "db".
Overlooked: Even the same parts sound different. And different parts (e.g. cmplementary transistors) sound very different.
If a signal is modulated by only one part, whose character (current: design, diameter, material etc.), the signal remains "cleaner" than if it is modulated by different parts, different characters.
Therefore distinguish SE and PP and complementary parts PP instead of Classe A, A/B, B...-)
If a signal is modulated by only one part, whose character (current: design, diameter, material etc.), the signal remains "cleaner" than if it is modulated by different parts, different characters.
Therefore distinguish SE and PP and complementary parts PP instead of Classe A, A/B, B...-)
No - but there is a (quite high) constant pressure in the atmosphere. Around 1 bar at sea level.
In other words: "sucking in" air is actually the exterior pressure pushing air into the lungs.
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Hi and thanks a lot for the very helpful advice I think to remember that maybe Perreaux was using only matched NPN devices in their amps output stages ?
i am quite ignorant but i have noticed a different dissipation on the two sides + and - of an amp with the PNP dissipating much more than its complementary NPN
Old amps due to the lack of PNP used only NPN devices I remember a Harman Kardon Citation Twelve for instance
very interesting indeed The weird thing is that while SE are very popular for tube amps are quite an exception for solid state amps
Maybe a good approach is low power SE amp and high efficiency speakers ?
What is also overlooked: most tube amplifiers are concepts with few stages, rarely more than 3. With transistors it usually ends in parts graves. Rarely less than 5 stages. With all preamps often well over 10. It's a sound horror. Has nothing to do with audio or hi-fi. The developers were not trained in methods of appropriate assessment of quality (audio), but also not in hearing (principle and physique, and psyche), and also not in influencing the current by the components, through structure and material and more,.
For audio amplification I recommend: as little as possible. Because the ear perceives the modulations. So if you are sounding a 12 square meter room, you only need a small 1-stage SE, whether tube or solid state. If you have 30 square meters of sound, you use a fat 1- or 2-stage. If you have 50 square meters of sound, you'll use a fatter 1 or 2-stage;-)
Real PPs also work when it comes to saving electricity.
Complementary push-pull actually has no place in audio, hi-fi. But there are some very cool concepts that are a lot of fun: party and all.
Complementary push-pull, half-wave unbalanced, and/or even umpteen stages, is only good for gyms or garden parties, but not for audio;-)
For audio amplification I recommend: as little as possible. Because the ear perceives the modulations. So if you are sounding a 12 square meter room, you only need a small 1-stage SE, whether tube or solid state. If you have 30 square meters of sound, you use a fat 1- or 2-stage. If you have 50 square meters of sound, you'll use a fatter 1 or 2-stage;-)
Real PPs also work when it comes to saving electricity.
Complementary push-pull actually has no place in audio, hi-fi. But there are some very cool concepts that are a lot of fun: party and all.
Complementary push-pull, half-wave unbalanced, and/or even umpteen stages, is only good for gyms or garden parties, but not for audio;-)
It partly depends on what one chooses to consider the reference (or middle, or zero) point, since amplitude can be relative.
For example I would not usually choose to (electromagnetically) only push a typical speaker cone, since they rest in the middle and so half the available excursion would remain unused. It would, though, be possible to make a driver which came to rest at one end of its travel, and then only push it to create sound at equal amplitude to a normal one. This isn't normally done for practical reasons (needing twice the one-way travel with equal linearity), but the emerging sound waves would otherwise be identical.
For example I would not usually choose to (electromagnetically) only push a typical speaker cone, since they rest in the middle and so half the available excursion would remain unused. It would, though, be possible to make a driver which came to rest at one end of its travel, and then only push it to create sound at equal amplitude to a normal one. This isn't normally done for practical reasons (needing twice the one-way travel with equal linearity), but the emerging sound waves would otherwise be identical.
Hi very interesting i would be curious to know what is your amplification of choice I guess tube single ended ?
If the push phase is so unnatural could a powerful diode placed at the output be a solution ? the current will flow only in the push direction
The idea of simple circuitry is very very fascinating to me Usually low power amps have less components and some of them have had a great success
To fill a big hall with sound as you say high power amps are usually needed But in a domestic situation a high efficiency speaker can allow for the use of limited power amps. I like the approach a lot.
I assume an SE also pushes and pulls;-)
And if we put a diode at the output of a PP, wouldn't we hear a half-wave only?
It is possible that this text above refers to the power supply units - basically.
I know many transistors that are unsuitable for audio, but also many unsuitable tubes - and diodes and resistors and caps and so on. Unfortunately, the quality of the parts in audio is fundamental. If you test 50, you are left with 5 suitable ones. And: every batch sounds different;-)-; This is another reason why the simpler the better.
But the vast majority of audio enthusiasts don't even know how to place the speakers;-)
And if we put a diode at the output of a PP, wouldn't we hear a half-wave only?
It is possible that this text above refers to the power supply units - basically.
I know many transistors that are unsuitable for audio, but also many unsuitable tubes - and diodes and resistors and caps and so on. Unfortunately, the quality of the parts in audio is fundamental. If you test 50, you are left with 5 suitable ones. And: every batch sounds different;-)-; This is another reason why the simpler the better.
But the vast majority of audio enthusiasts don't even know how to place the speakers;-)
Not really. But "absolute pressure" and "pressure variations" are muddled up here. First of all you have the atmospheric pressure. As stv wrote, this is about 1 bar at sea level. Sound is not an absolute pressure, it are pressure variations around the atmospheric pressure.
Look at it like you have a very large DC (static) part which is the atmospheric pressure and some very tiny variations (positive and negative) like an AC part (dynamic). A tiny bit more and a tiny bit less pressure then atmospheric, very fast one after the other.
Our ears are made so they only react to the very small variations because one side of the eardrum is connected to the outside by your ear (obviously) and the other side of the eardrum is connected to the outside by Eustachian tube to your nose-throat. That tube works as a filter so that the tiny variations don't get to that side but they do get through your ear to the other side. So your eardrum reacts to sound.
So sounds does make the pressure "go negative" relative to the atmospheric pressure. Likewise it makes it go positive relative to atmospheric pressure. This is what counts.
Air is a very linear substance. Certainly so over the values we are looking at when talking about sound. So I have no idea where the idea comes from that it has second order distortion. At very large sound pressures air becomes non-linear but then we are going beyond 130 dB, like a starting Saturn V.
Gino, can you hear the one hand clapping, or... was it, the other hand being clapped..? :)
quoting part of an earlier post:
quoting part of an earlier post:
I am thinking at moment of the construction of hearing or semi-closed loudspeakers, or even microphones - already mentioned above. We attenuate the negative component with these loudspeakers and microphones.
I would like to point out another characteristic. Mechanical and electrical systems are frequency, vibrating systems. A excited string ("single frequency by leght, thickness...) of an instrument vibrates at different frequencies: "overtones". And the excited ear as a vibrating system also vibrates with "overtones". And electrical systems also produce these, are oscillating systems.
By the way: a guitar, for example, consists of strings, but also of an instrument body. Not only does the string vibrate, but the body is also stimulated - intentionally and unintentionally. Not only the length, thickness and material of the strings, but also the material, the body, size and structure of the sound body and more make up the sound. Would someone build a guitar only according to some frequencies, tones to be played, e.g. basic frequencies of the 6 strings, he would be described as crazy, or mad;-)
And this also applies to seemingly purely electronic devices. Material resonances, for example, also modulate the electric current in the audible range. It is not enough to pay attention to just two or three frequencies or a few overtones.
I would like to point out another characteristic. Mechanical and electrical systems are frequency, vibrating systems. A excited string ("single frequency by leght, thickness...) of an instrument vibrates at different frequencies: "overtones". And the excited ear as a vibrating system also vibrates with "overtones". And electrical systems also produce these, are oscillating systems.
By the way: a guitar, for example, consists of strings, but also of an instrument body. Not only does the string vibrate, but the body is also stimulated - intentionally and unintentionally. Not only the length, thickness and material of the strings, but also the material, the body, size and structure of the sound body and more make up the sound. Would someone build a guitar only according to some frequencies, tones to be played, e.g. basic frequencies of the 6 strings, he would be described as crazy, or mad;-)
And this also applies to seemingly purely electronic devices. Material resonances, for example, also modulate the electric current in the audible range. It is not enough to pay attention to just two or three frequencies or a few overtones.
yes you are right I was just wondering about the emphasis on the two different topologies
like push pull and not push pull There must be differences
interesting I would use parts used in equipment with good sound Of course i am not looking for a high end experience
Many units said to be good sounding have normal parts Nothing fancy For me it would be enough
i think that many enthusiasts do not have the right room I have seen in videos equipment for thousands of dollars put in not treated rooms
They will never show their full potential for sure