It has major sound repercussions. As many designers will address the weaknesses of each configuration you will be less able to hear that sound effect on the driver , but if you switch amplifiers types you will be able to hear a great difference in the way music is presented. It is a matter of matching the right amp with right speakers.
With class d amps high power low cost great sound, theses amplifiers are going to be history, like vinyl.
There is room for every format and design, we're all different. I abandoned vinyl many years ago and deeply regret it now, despite having a significant Roon library of bit perfect flacc files and a few very nice DACs, like some people have different cartridges. I miss the process of thinking about which album to play, taking it out and starting the turntable, placing the arm gently on the plastic and then turning up the volume to hear the warm, immediate, vibrant and life like voices of the artists and their instruments. I often wonder what it would be like to hear artists like Clare Teal, Oscar Peterson, Anne Bisson, Suzanne Vega and especially the likes of Renaud Garcia-Fons on a really nice Linn LP12.
Instead I start Roon, choose the endpoint, maybe my Chord Qutest in my office, then choose a track and press play. It's very quick and easy and the sound is detailed and accurate. If I get bored I click a few times and something else appears in the room. I might change to the Denafrips DAC. It's too easy, plus the amp and speakers become more important as they need to reproduce the musicality and vibrancy missing from the digital reproduction. The Chord is way better than most DACs but having heard friend's analogue systems, it's a fantastic DAC but a pretty poor second to a good turntable setup, when it comes to making music come alive.
You can do that with S.S., but it's typically not done because of easy availability of complementary pairs of transistors. With tubes you don't have that, so designs are more likely to show up using a single ended output stage approach.
It’s not typically done because of the efficiency advantage of push pull, where the bias current only needs to be 1/2. And it CAN run into class B if the current demand goes above 2*Ibias. SE simply cannot do that. That old NP amplifier from (I think) 1976 did sound pretty damn nice. But modern design and components can equal the sound quality with class AB. In 1976, hell no.
No, but class AB bias for tubes is closer to what Krell calls “Class A” than a “normal” class AB amplifier. The fraction of full signal current used with tubes tends to be quite high - high enough that the idle dissipation is higher than under full drive. Usually set at or near the plate dissipation rating. Why? They actually use the gm-doubling phenomenon to aid in linearization.
yeah, but you cannot say class A in tube is class A in transistor . it is not the same circuit, so it will sound different.
it is just important to compare apples with apples. Class A in transistor is just a 'bias' usually of a class AB stage with higher current at idle. This is just one difference.
second difference, if you think a Class AB in transistor is the same, no , it has complementary devices,
In tube it has usually a balanced signal, and only one power supply pole.
Few class AB transistors amps have a single polarity power supply, that makes it very hard to draw a bridge with different devices.
Just that to keep in mind!
it is just important to compare apples with apples. Class A in transistor is just a 'bias' usually of a class AB stage with higher current at idle. This is just one difference.
second difference, if you think a Class AB in transistor is the same, no , it has complementary devices,
In tube it has usually a balanced signal, and only one power supply pole.
Few class AB transistors amps have a single polarity power supply, that makes it very hard to draw a bridge with different devices.
Just that to keep in mind!
Doesn’t matter if it sounds different between tubes and transistors. Class A is class A, defined by the conduction angle. If it moves into class B at high loads, it’s technically class AB. It may stay in class A at 8 ohms and move into AB at 4 when the current demand doubles. It’s better than clipping early. Some of those “class A” Krell amps don’t even have enough bias to stay in class A for the full 200 watts even at 8 ohms. If they did you’d need liquid nitrogen to cool them.
In single ended class A there is simply no mechanism available to move into class B without clipping. Then the transistor/tube might cut off entirely for part of a cycle. Since there isn’t another side to take over you get stuck with gross distortion.
In single ended class A there is simply no mechanism available to move into class B without clipping. Then the transistor/tube might cut off entirely for part of a cycle. Since there isn’t another side to take over you get stuck with gross distortion.
In audio the amplifier never goes into clipping, if it starts then it should do it softly and fast recovery.
Single ended class A, I Think it refers to one or more devices in parallel driving the load with no complementary group to pull the signal in the other opposite phase. The whole signal with its entire form is reproduced by that group of devices.
Class A means that constant current DC is sufficient to enable the said devices to drive the load without turning off due to combination of voltage and currents going through.
Class AB is when there are devices pushing and pulling the signal when the signal exceeds Class A current. It is only possible with devices each sides of polarity in reference to the output, the device will operate in Class B for a short time and the lower signals will be in Class A.
Even Class AB operate a lot in class A and. Vice versa
If you have a single ended device and it can reverse current you will say it is class B , it is good if it can achieve it.
BJT's can also be run at high enough bias so that dissipation decreases under load, but this is not commonly done.
Ed
What does it really mean "not the same circuit"? Why would class A in tubes be any different? Take a SE tube circuit, replace the tubes with transistors, change the output transformer ratio a bit and voila, there is a SE class A transistor circuit. Same with push pull, a transistor PP circuit can duplicate the tube PP topology if required. It is seldom done since the 60s, but certainly possible.
The same requirements for class A, stated in #31, are equally applicable to both transistors and tubes. Yes, they will sound different but that is kind of obvious.
Class A means that the output device, whatever kind it may be, is running constant current all the time.
Actually what you really want if you can tolerate the heat is to run your solid state amp Iq at Vcc/10RL. That’s a very high bias AB, right at the maximum dissipation. That would keep the junction temperature fairly constant under dynamic loading. It would minimize bias mistracking as the transistors would run at a near constant temperature. That would require heat sinks (and transformer) the size of what was used back when they were enforcing FTC power preconditioning.
you refer to this :
https://www.audiodesignguide.com/SolidState2022/index.html
it is some type of cyclotron?
https://www.audiodesignguide.com/SolidState2022/index.html
it is some type of cyclotron?
Cyclotron is a particle accelerator. Canada has the largest one built at 17m (56ft).