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non-linear Class-A amp with fun sound

Salt

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So declare [resolved] to header....
 
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AMKAM

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how about SS amp with tube-amp
and is ifi audio pro ican signature also Class-A amp. pro can reviews looks all in one desire.
 

Zek

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@AMKAM Are we talking about headphone amplifiers or A-class amplifiers in general?
 

raindance

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Most/many headphone amps are already class A. People keep responding about speaker amps which is off topic.

There are a myriad things that determine how non linear an amp is, for example lower negative feedback.
 

SuicideSquid

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Most/many headphone amps are already class A. People keep responding about speaker amps which is off topic.

There are a myriad things that determine how non linear an amp is, for example lower negative feedback.
My understanding was that most of the high-performance headphone amplifiers we see coming out now either use class a/b opamps, or use multiple opamps in a composite configuration which is very similar to / is a Class A/B design. I'm not an engineer and could be mistaken but given that the pure Class A designs advertise that in big bold letters to court audiophiles, that's how I've understood it.
 

DonH56

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I don't think anyone ever embraced Class F amplifier topology.
I am just sayin'.
;)
Not for audio, but it works well for some RF/pulse applications... Class C hasn't been popular for audio, either, nor E, though pure class B has been used in the past (by McIntosh, among others).
 

Galliardist

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Not looking for the best, but for money's worth and performance that can be heard.
Let's get real here: I don't have much in-person experience with Class-A amps, but I heard they are very powerful and linear from reviewers. From this, what I am looking for is a fun, warm sound with not much linearity and a huge sound stage with depth and width while keeping the detail, imaging, and technicalities intact. In these sound profiles, I found these amps: the EarMen CH-Amp, the Burson Audio Soloist 3X Performance, the Burson Audio Soloist 3X Grand Tourer, and the HeadAmp GS-X mini, so from these, you can see my price range maxing out at $2500. With these, I am mixing a tube amp that has full tube output, and I decided to buy the xDuoo TA-22.
Now my setup will be a DAC (Fiio K9 Pro or Cayin RU6) with balanced output to an xDuoo TA-22, which has tube-full output but with RCA out only, to a Class-A amp to balance headphones.
What will I be using this setup for? Mostly movies and TV shows.
I know I am crazy and asking for a lot, but I am very curious. I would love to have an opinion about Class-A amps in this setup and which will be best, or maybe even go in a different direction and save money.
Firstly, welcome to ASR, again.

We are under orders to be nice to newcomers, but I can't also be restrained about this question. Sorry.

You see, you appear to have ingested lots of - should we call it information? - no, stuff, from all over the internet and elsewhere, and contrived a frankly dumb setup and question to ask here - a place that you have obviously not read the basics from,

Why is it dumb? Well, you haven't thought about the requirements of headphones for listening to movies and TV shows. Also, you appear to be asking for a setup with a distorting "fun" sound, but all of the advantages that really only come with a nonidistorting sound: to wit, "keeping the detail, imaging and technicalities intact". I'm not sure that you really mean all of this, because a lot of audiophiles run a balancing act - or try to - of keeping enough of the detail and technicalities in place.

However, let's come at this from a different and more sensible angle. You are going to listen primarily to movies and TV through headphones. I'd suggest that the main priorities for that are a fairly wide soundstage, the best possible performance in the human speech range, a reasonably good bass performance and a strong centre to that soundstage. I'm describing how you will best get to hear dialogue/speech, which is the most important thing with movies and TV. Forget the "fun" angle because it will make speech harder to hear.

So you have two possible routes to go. The conventional one is to choose headphones with a wide soundstage such as the Sennheiser HD 800S (the classic but expensive example) and a good, accurate DAC/amp that can drive it. There's a review thread for the HD 800S here with a lot of responses including examples of equipment used with them.

You'll see references to EQ (equalisation) and the Harman curve (a target response for headphones based on research, which requires boosting the bass) in the thread.

You can choose whether or not to drop the class A requirement, it will make little difference except possibly for price. Since I'm suggesting most of your budget to to the headphones - which is always a good idea - you may have to drop it. No matter.

I imply from the question that you already have the xDuoo TA-22 - which from the listed specs will drive the HD 800S through the XLR balanced output anyway, is a DAC, has at least a low enough distortion figure for real world use (even if it might get a headless panther here in practice). Why then use its RCA outputs (unbalanced) to a separate class A amp to balanced headphones? That is the very definition of a waste of money. The TA-22 is missing equalisation, if you find you need that you'll need to add something that can do it into the system.

Now, I mentioned a second route. That is to pursue Dolby Atmos/surround sound through headphones for something like virtual surround. I'm not going to try to describe that route since I don't yet have the experience to do so. If your listening is highly balanced to movies rather than TV and online videos, it might pay off.

My advice if you have the xDuoo already though, is just get some decent headphones and get on with listening. There's not much point in worrying about feeding it with another DAC and sending sound to another amplifier to be honest. If you ffeel you need to change things later, add in a component to do EQ to match what you need. If you really can't get good consistent speech, a possible, then replace the xDuoo with something with a good review here.


for anyone else who wants to reply, there are the specs...
 

raindance

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My understanding was that most of the high-performance headphone amplifiers we see coming out now either use class a/b opamps, or use multiple opamps in a composite configuration which is very similar to / is a Class A/B design. I'm not an engineer and could be mistaken but given that the pure Class A designs advertise that in big bold letters to court audiophiles, that's how I've understood it.
Yeah, I think you are right, my knowledge is outdated...
 

MaxwellsEq

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is it same case when driving efficient headphones?
It is always the case regardless of the type of thing you are driving.
 

MaxwellsEq

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If you go to college to study electronics, one of the first things you will work on is a single transistor amplifier.

Part of this design approach requires getting the DC characteristics right such the transistor operates in its safe zone and is always on. Because the transistor is always on, it's a class A amplifier. This is the easiest design to build and do the mathematical analysis on.

The very simplest amplifiers with the smallest component count tend to be non-push-pull class A amplifiers.
 

Killingbeans

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Killingbeans​


Well, you did say:

I would love to have an opinion about Class-A amps in this setup and which will be best, or maybe even go in a different direction and save money.

Distortion is cheap. Bias any amp circuit to run outside of its comfort zone, and you have it. Any blind monkey can design an amp with distortion.

Even if it isn't distortion you want, but just a funky frequency response, it only takes a few dirt cheap resistors, capcitors and some basic electronics knowledge to either throw in a few simple filters and/or mess up the output impedance.

It's not amp class inherent/dependent, and there's absolutely no need to dish out $2500 to get any of it.

My advice: Assuming you're using a PC as source for your movies and TV show watching, spend $100 to 200 on a headphone amp that's proven to be high performance*, and then use Equalizer APO + plugins to get all the "fun", you can dream of, for free. That saves you at least $2300. You're welcome :p

*With measurements, not lyrical marketing and user feedback.
 
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AMKAM

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So declare [resolved] to header....
i am a complicated guy
:)
:p
Firstly, welcome to ASR, again.

We are under orders to be nice to newcomers, but I can't also be restrained about this question. Sorry.

You see, you appear to have ingested lots of - should we call it information? - no, stuff, from all over the internet and elsewhere, and contrived a frankly dumb setup and question to ask here - a place that you have obviously not read the basics from,

Why is it dumb? Well, you haven't thought about the requirements of headphones for listening to movies and TV shows. Also, you appear to be asking for a setup with a distorting "fun" sound, but all of the advantages that really only come with a nonidistorting sound: to wit, "keeping the detail, imaging and technicalities intact". I'm not sure that you really mean all of this, because a lot of audiophiles run a balancing act - or try to - of keeping enough of the detail and technicalities in place.

However, let's come at this from a different and more sensible angle. You are going to listen primarily to movies and TV through headphones. I'd suggest that the main priorities for that are a fairly wide soundstage, the best possible performance in the human speech range, a reasonably good bass performance and a strong centre to that soundstage. I'm describing how you will best get to hear dialogue/speech, which is the most important thing with movies and TV. Forget the "fun" angle because it will make speech harder to hear.

So you have two possible routes to go. The conventional one is to choose headphones with a wide soundstage such as the Sennheiser HD 800S (the classic but expensive example) and a good, accurate DAC/amp that can drive it. There's a review thread for the HD 800S here with a lot of responses including examples of equipment used with them.

You'll see references to EQ (equalisation) and the Harman curve (a target response for headphones based on research, which requires boosting the bass) in the thread.

You can choose whether or not to drop the class A requirement, it will make little difference except possibly for price. Since I'm suggesting most of your budget to to the headphones - which is always a good idea - you may have to drop it. No matter.

I imply from the question that you already have the xDuoo TA-22 - which from the listed specs will drive the HD 800S through the XLR balanced output anyway, is a DAC, has at least a low enough distortion figure for real world use (even if it might get a headless panther here in practice). Why then use its RCA outputs (unbalanced) to a separate class A amp to balanced headphones? That is the very definition of a waste of money. The TA-22 is missing equalisation, if you find you need that you'll need to add something that can do it into the system.

Now, I mentioned a second route. That is to pursue Dolby Atmos/surround sound through headphones for something like virtual surround. I'm not going to try to describe that route since I don't yet have the experience to do so. If your listening is highly balanced to movies rather than TV and online videos, it might pay off.

My advice if you have the xDuoo already though, is just get some decent headphones and get on with listening. There's not much point in worrying about feeding it with another DAC and sending sound to another amplifier to be honest. If you ffeel you need to change things later, add in a component to do EQ to match what you need. If you really can't get good consistent speech, a possible, then replace the xDuoo with something with a good review here.


for anyone else who wants to reply, there are the specs...
Thanks for being straight-forward and nice at the same time.

I do feel like I will waste a lot of money going in that direction, and also, reading all the threads, I feel like it's not doable.

When it comes to headphones, I already have the Fostex-T50rp Mark 3 and HarmonicDyne Zeus, which I use a lot for movies. I want to buy DC Aeon 2 Noire in the near future. I haven't experienced HD 800s in person, but I heard they lack a lot of stuff in the middle for a large soundstage.

What you said about the Ta-22 and your general idea about tube amps make sense. The Ta-22 stand-alone unit looks just fine for a first-time tube starter.

I'm really confused about the Class-A amplifier in general.
 

Galliardist

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i am a complicated guy
:)
:p

Thanks for being straight-forward and nice at the same time.

I do feel like I will waste a lot of money going in that direction, and also, reading all the threads, I feel like it's not doable.

When it comes to headphones, I already have the Fostex-T50rp Mark 3 and HarmonicDyne Zeus, which I use a lot for movies. I want to buy DC Aeon 2 Noire in the near future. I haven't experienced HD 800s in person, but I heard they lack a lot of stuff in the middle for a large soundstage.

What you said about the Ta-22 and your general idea about tube amps make sense. The Ta-22 stand-alone unit looks just fine for a first-time tube starter.

I'm really confused about the Class-A amplifier in general.
I don't hear anything missing centrally in the HD 800S. The Aeon headphones may be a good step up for you.

You don't need to worry about amplifier class and even less so for headphone amps which are low powered. I'd worry about the performance, whether the amp will drive the headphones you prefer, and about features.

On tube amps, again they are something I wouldn't buy. But don't let that put you off. It's an irrational thing with me, especially as I've heard some good systems with them that I liked. You happen to have one that will probably suit your needs, so why worry?
 

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SuicideSquid

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I'm really confused about the Class-A amplifier in general.
As Galliardist said, if it's confusing you, don't worry about it. As I said in my previous post, all solid state amplifiers that are properly designed will sound the same. My arguments about not buying Class A were mostly about paying a price premium.

If you want a really great headphone amp that's going to drive everything you throw at it with extremely low noise and distortion and work with different dacs and preamps, look at the Topping L50 and A90, pick the one that has the features you need, and never worry about amplifiers again. Both are effectively "perfect" headphone amps in that they take an incoming signal and boost it without colouring it in any way, and without noise or distortion.
 

fpitas

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from a time when designing stable feedback loops was troublesome, and zero crossing distortion was instead brute force combated by wasting tons of power on nothing.
Honestly the biggest improvements were in circuitry that accurately controlled the idle current over time and temperature, and during large output swings. Nelson Pass (for example) was one of the pioneers with his optocoupler A/B bias control. These days, Benchmark has a relatively low-power feedforward approach.
 

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AMKAM

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Well, you did say:



Distortion is cheap. Bias any amp circuit to run outside of its comfort zone, and you have it. Any blind monkey can design an amp with distortion.

Even if it isn't distortion you want, but just a funky frequency response, it only takes a few dirt cheap resistors, capcitors and some basic electronics knowledge to either throw in a few simple filters and/or mess up the output impedance.

It's not amp class inherent/dependent, and there's absolutely no need to dish out $2500 to get any of it.

My advice: Assuming you're using a PC as source for your movies and TV show watching, spend $100 to 200 on a headphone amp that's proven to be high performance*, and then use Equalizer APO + plugins to get all the "fun", you can dream of, for free. That saves you at least $2300. You're welcome :p

*With measurements, not lyrical marketing and user feedback.
Ya i run through pc with KMplayer and will try Equalizer APO
 
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