What are the differences between Class A, AB, and Class D amplifiers?
What are the differences between Class A, AB, and Class D amplifiers?
Confused about the differences between Class A, Class AB, and Class D amplifiers? Join Paul as he explains the differences between these different amplifier classes. Have a question you want Paul to answer? No problem. Just head to http://www.psaudio.com/ask-paul/
Do the current model PS Audio Stellar amplifiers use the new B&O amp module like the Bel Cantos or do they use the previous version? thanks-
Why do we have two vOmin values in calss A amplifiers?
Hi. I have a question. I love
vintage hifi from 80’s-90’s. I buy many old equipment and I noticed that they sound
much less clearer (much less treble) than what they were sounding when they
were new. What’s getting old in them? Is it the old capacitors acting as filter? What’s the reason they sound
much less clearer? THX
Paul u da mane
I love it! I did not realise the heat is lower in class A during a max use (the speaker gets hot versus silence) that is a very good point! Then again maybe the impedance is higher for silence versus a sine wave? Either way, its the best explanation I’ve seen! Best Class D also. Class A/B for me now is the most mysterious. How does a A/B amp notice the zero crossing? I guess it fades to zero when the bias goes negative and there is a small cross-over when both sides run.
I would describe a "class A" power amplifier as basically just a small signal amplifier stage scaled up, i.e. a transistor conducting half its maximum current when no signal is present. Then the "class B/AB" power amplifier instead being two mirrored transistor stages taking turns on the positive and negative sides of the signal. The downside of B/AB being risk of crossover distortion and the upside being almost no static current draw (just a minor bias current to overcome the non-linearity of transistors near zero current).
hi, some studio monitor using class d amp as said. when there is no audio signal , there is a hiss sound come out from the tweeter . is that normal? or need to fix?. not only the studio monitor , other electric guitar and instrument making a hiss sound too, thanks in advance.
Yes this old person talks a lot and the same thing over and over again. But the fact remains that they hardly talk about some very small but important issues. Just a example have never seen anyone discussing the sound parameter adjustments in a av receiver which is in the audio set up. And lot of unnecessary talks
Okay Mr. Smarty pants…..what did we miss?….there’s A, and then B, then AB…..there IS a letter between B and D!
Jesus, they let anyone on YouTube anymore………………meh
*Your voice is class A clarity*
Class A amp’s are preferably more musical and defined. Class AB would share some of their characteristics. Tubes that are designed in this way preferably with class A would be the creme de la creme as in earlier Marantz products. Good review.
This is both good knowledge and skill. Thanks!
You know, many have this kind of knowledge but can not pass it on to others using crayons like you have satisfactorily done.
I’m following you from now on
Thanks so much
Difference is that, class D are for people with small D#&5s, Class AB is better, but still small D#&5s, Class A is the sh#%.
thank you i learned something
Hello, little mistake about the class A amp.
An idle amp don’t consume 100% of the nominal power, but only 50%.
Nicely explained and very lucid. I didn’t really understand class D, do now. So now that you’ve closed one "can of worms", where does Hitachi’s class G and Soundcraftsmen’s class H fit in and are they a viable alternative??? Also what the heck is Carver’s Magnetic Field amp???
Very informative video. Didnt expect class A amps to be thr least efficient, tho.
Hi I have a pair of Arphi Super Challenger speakers. 50 watts RMS each Chanel. These are 42 year old speakers. Please suggest me an amplifier to match the wattage of the speakers. Thank you.
learned a lot from that short video thank you!
First time viewer and instantly subscribed because Paul is awesome 🙂
To answer the question:
Class A: is wasting power
Class AB: is wasting less power as much as the designer allows to run quiescent current trough the amplifying devices
Class D: No more power used as required to do the job.
The Class of an amplifier doesn’t say much about the quality though.
I’ve had harsh sounding heavily biased amplifiers (Krell) that didn’t sound sweet at all and sweet sounding Class AB amplifiers (Conrad Johnson, Jeff Rowland) that where moderately biased to only produce ten Watts in Class A.
So the generalization here about the Classes of amplifiers and their sound is nonsense.
All things equal: If you can afford it choose an amplifier with a healthy big powersupply, lots of output devices in parallel and chunky heatsinks.
The advertised RMS wattage of class D amps seem to be overrated.
Thanks! 73 de ve3hip in Welland Ontario Canada 🇨🇦
Hey, where’s the class C amp?
hey, I ripped into some old commercial airline headphones and one of the speakers measured 30 ohms. How is the best configuration to amplify at different loudspeaker impedance?
Very good explanation. Thank You
Sir, my name is Daniel, I live in Sweden. I’m looking for help please. Can you please help me to recommend power amplifier for my speakers? I have 6 pieces of Meyer MSL-3 speakers and 2 pieces JSL Sound concert system bass speakers. Power: 1000 watts RMS. IMPEDANS : 8 OHMS * 2. Notes: if anyone can be a help, I was really appreciate thanks 😊.firstname.lastname@example.org
Hi, good evening (Indian time).
I have a question to ask. Whether stylus for 78 RPM records fits on regular magnetic cartridge or cartridge itself is different for 78 RPM records along with suitable stylus.
This is just a good pure hearted man of a person, thank you kindly sir for this Info.
Almost 100k subscribers
Thank you!! Very instructive
I really like the way you explain stuff. Are your products available in Europe?
Whichever company that figures out how to deal with the "complications" of making a great class D amplifier, and offer a 5.1 or 7.1 surround receiver using class D tech, at an affordable price and in a compact design will get my $$$ – just a matter of time! I love how good my Lepai TA2020 sounded (after fixing noise issues) for only $20-$30.
Definitelly keep that up if you are.
Does a gain cell pre amp sound different (as in, less faithful to the source) than say, an Ayre K-1, Benchmark LA4 or Bryston BP-26 pre amp? I love PS Audio but I can’t do A-B comparisons between any PS Audio Gain Cell pre amps and the others and I don’t want to take a step back. Thanks Paul you are the best!
QSK QSL! =]
Class d sucks
Wow you explain very well 😀 Thanks so much!!! I didn’t understand if I have 3 differents amplifier well built A-AB-D
it doesn’t matter which one I choose because they all sounds good or class A is better anyway? Thaaaankssss
class d amplifiers are less heavy not ?
In the 70’s I had a class A power amp, "Ampzilla" by Great American Sound. It ran so hot, it had two cooling fans and kept my room warm, summer and winter. I didn’t like the sound. Not dynamic at all. Plus it was prone to sudden, catastrophic failures, and had to be sent to California to be repaired. Finally, GAS went bankrupt. I bought a class AB power amp, the NAD 2200. What a difference. Great amp, great sound. Still going strong today. After 32 years, only had to replace the output relays, which were of very poor quality.
But what about a Classe amplifier?
Man,i head my head tilted to the side, like your dog in the back, listening… lol
What is a class C then?
Could anyone test out my application? Encounter: androidcircuitsolver/app.html
Hi, I was watching this video and would your help or advice on what amplifier to buy. I have really good speakers JBL ES 90 BK and using Denon AVR -S500BT Receiver.. I feel like I am not getting the full potential of my JBL since they can max at 400 Watts. While my Denon Receiver powers only 75 Watts per channel. I don’t have lots of money so I am looking for a good budget class AB amplifier. Not very expressive but good enough to boost my Denon . I can combine the external amp with Denon through pre- out
Great explanation. Many thanks.
Thanks a lot I Finally Understand it