Understanding the Appeal of Cheap Class A/B Amplifiers: Your Thoughts?

[Barrelhouse Solly]

This reminds me of the early days of solid state amps. There were quite a few poorly designed or cheaply implemented solid state amps on the market in the early '70s. Also the odd order harmonic distortion they produced was "harsher" sounding than the even order distortion from tube amps. It clouded consumers' minds. A good solid state design was better than a good tube design at the same price. One of the basic principles of engineering in any field is that it's very rare for there to be only one good solution to a problem unless there's a technological breakthrough.

 

[Elitzur–Vaidman]

It seems these class a/b amps are not for audiophiles at all. However, there are still many people keeping buying them. Probably mainly because of the numerous functions and connectivities? Like Karaoke, FM radio, SD card, Bluetooth, etc.

I think these class a/b amps are for the people who have bought into the audiophile myth that class a/b amps have some sort of special magic to them, but cant afford to buy the sterophile recommendations. I went through a similar process buying a class d/tube hybrid as my first real amp.

 

[frabor]

We have to accept that most users do not care or understand pages of multicolor graphs with numbers , but they understand that 125Watts is MUCH better than 95W and if distortion numbers starts by a zero, so it has to be good. These units provide lots of inputs, with a lot of led lights and good functionality for a low price. They have sound, cute led lights and are cheap. What's not to like! :0)

Twisting the argument a little bit. Most avr (well almost all below $2000 or Euros) are AB, they have nice led, they amplify sound but their sonic specs are from acceptable to substandard compared to the stereo equipment tested here, even the ones far below that price mark. Yet people keep buying these to listen to music and vinyl other that the avr purpose (now most Denon AVR have a phono input that was absent for years). The more outputs and more three letter music standards an avr does, the better the avr will be and sound, doesn't it?

Sometimes ignorance is a bliss and knowledge is a burden.

 

[Waxx]

The reality here in Europe (or at least in Belgium) is still that they want the classic look, and don't care what's in it as long as it's functional and good sounding to their standards (that is not high to ours). Most music lovers are not technical at all and our complex systems with dsp, multichannel and room correction is way too complex.

I had a family reunion last weekend, and again the question came to advice for a simple "receiver" that sounds good and has DAB (radio) build in. The family member who asked is not technical at all and a bit older. Connecting the cd player and turntable and the speaker cables is already a challenge for them. The speaker are old (1970's) but still mint Kenwood speakers and their old Pioneer "receiver (integrated amp with fm radio build in) died.

A Yamaha R/S202 DAB+ is what fits their needs the best. It's relative cheap, it works well and is all in one, they just have to connect the cd player and record player and the speakers. It's like a drop-in of their Pioneer, but with DAB+ in stead of FM/AM radio. They don't care about sinad and dsp/room correction. They just want their system working again more or less as before. And the Audiophonics digital integrated amp (that was discussed here before) is already to expensive and complex for them. I did suggest it but they did not want it.

And even with a lot of younger people, it's like that. That is why those big brands of the past keep selling the old receipe (sometimes with a streamer or DAB build in) and why those crappy AB class amps on alieexpress sell. And they will keep doing it untill the newer more advanced system are as userfriendly as those for technical noobs.

 

[thewalkingboss]

I just think they sound better than class D amps. Don't know why. I'm an electrical engineer and learned how to build class a/b amps in college. I have 3 Pyle receivers ($45) that are connected to my computers and drive '80s era Realistic Minimus 7's ($50). Great sound for less than $100 per computer.

 

[wpo7]

I just think they sound better than class D amps. Don't know why. I'm an electrical engineer and learned how to build class a/b amps in college. I have 3 Pyle receivers ($45) that are connected to my computers and drive '80s era Realistic Minimus 7's ($50). Great sound for less than $100 per computer.

yes I agree, though I found it odd that when I contacted Pyle they claimed the amp (PTAUWIFI46) is a class D not a/b

 

[IPunchCholla]

I just think they sound better than class D amps. Don't know why. I'm an electrical engineer and learned how to build class a/b amps in college. I have 3 Pyle receivers ($45) that are connected to my computers and drive '80s era Realistic Minimus 7's ($50). Great sound for less than $100 per computer.

Well, the one Pyle amp measured hear has distortion in the audible range without being too high, so yours might sound different in a pleasant way to you.

 

[egellings]

I would say the following:
1. A first time buyer who doesn't really understand what they are buying so thinks buying something that 'covers' all the options they might need at the cheapest price- they are buying these because of the all the buttons and connections
2. I can imagine someone looking at these products thinks they are buying something with lots of options so won't need to buy something else

The reality is I imagine after they receive one of these they will hardly use it and probably ends up with a bad opinion of the sound quality that a 'cheap' amplifier can provide.

Hey, It's got everything on it!

 

[SIY]

I just think they sound better than class D amps. Don't know why.

Because you peek.

 

[Franzois]

Fosi Audio has always been committed to thoroughly understanding our user's needs and crafting our products based on those requirements. Currently, our primary focus in the amplifier sector is class-d amplifiers. However, we are well aware that class a/b amplifiers continue to maintain a strong fan base. In fact, many audiophiles prefer analog amplifiers, especially those produced by traditional, established manufacturers.

We notice that class a/b amplifiers priced under $100 are selling exceptionally well on Amazon. While we believe that these amplifiers may not deliver the best quality, they undeniably cater to certain needs of consumers. As an audio company, we are driven to diversify our product line to meet the demands of different customer groups.

In the past, we have produced a few similar models of class a/b amplifiers. However, after careful evaluation—particularly considering the quality control did not meet our own standards—we decided to put the development of these products on hold.

In light of this, we are seeking your opinions on budget class a/b amplifiers priced under $100. We hope that your ideas and suggestions can contribute to our future product development efforts.

Specifically, we would like to ask two questions:

1. Could you describe the demographic of individuals who buy and use these types of class a/b amplifiers?
2. Apart from the price, what aspects of these low-cost class a/b amplifiers appeal to their users?
View attachment 298636

Speaking about https://www.amazon.com/dp/B08H4R221Z/ typically?
I don't know if they're class AB (I'd be surprised if it's not class D, actually), but people appear to be very happy with their purchase, most of them being pleased with the sound.

Why are they so popular? Because they are very simple to use and very versatile, with apparently good enough power and sound (I don't own one): one power outlet, a pair of speakers and you're in business. I think that most people (including my wife and kids who are musicians) don't want separates because it is way too complex to use. I have three illustrations for that:

i) Take for example a V3 stereo. Can it play music on its own? No, you need a source, and an interconnect from this source to the V3, and a second power outlet. A receiver can at least stream bluetooth from your phone and usually play FM as well. If you want a second source (TV, CD/blu-ray player,... ), you need a preamp, more interconnects, and more power outlets. Worse, most of the time each separate comes with its own remote control. That's rapidly quite messy and not usable by non-initiates...

ii) The vintage market is going nuts for 1970-1980s receivers, while separates from the exact same lines of products, which usually were more expensive at the time, can be had for much cheaper... The look of the receivers may also have an influence.

iii) my own example: until about 6 months ago I had a Dsound D310 which was a fairly good Class D integrated amplifier with line in, several digital inputs and one remote control. It was used by the wholefamily without problem but died and is no more produced. To replace it, and since the E10 was already discountined, I bought a BT20A pro which sounds good enough, and can be used in bluetooth, but I had to buy a separate source (SMSL dac) which doubled the price of the system's electronics. It has clearly decreased the usability (and the use) of the system. I am thinking of replacing it with a decent receiver.

For the general public, IMO, you should aim for the feature set of the Sony STR DH190, which sells even better than the cheap do-it-all amps (2000 units sold in 1 month in the US according to amazon!). For the same price, with the sound quality we know you can deliver and with the addition of a pair of nice vu-meters, I think you'd have a winner.

 

[Doodski]

I don't know if they're class AB

From this image it appears to be a class AB.

 

[SIY]

From this image it appears to be a class AB.

Return to moukey?

 

[Clmrt]

1. Could you describe the demographic of individuals who buy and use these types of class a/b amplifiers?

I have a hard time pinning this down. The consumer would have a need to fill. They may not know how to research used gear, so they buy new. They have very limited funds. Intended use may be a centerpiece in a main system or in the shop out back. Educated buyers may have to place price as the primary concern and quality second. Features may be the primary driver and quality is not considered. Trust of used gear may be lacking - repair costs would negate any savings. More features, knobs and lights may translate to better value - more "anything" must be better.

2. Apart from the price, what aspects of these low-cost class a/b amplifiers appeal to their users?

This seems to assume they are specifically seeking out class A/B, or at least see it as a non-factor, or perhaps the stigma of Class D being inferior to the old standard.

I myself have both D and AB. I love vintage pro gear, I appreciate designs conceived in the 70s and 80s that have no major downsides. I have realistic expectations on performance and my inability to discern the issues others point to on paper. I consider speakers and room to be the major influence on sound so long as the gear upstream is well enough executed so as not to ruin the signal to the point of detection by ear.

 

[40th Anniversary]

Better late than never.
1. Easy connectivity = Bluetooth module will make it easy for anyone with portable music to stream to an amplifier.
(it could be an external bluetooth adapter - but nice if it was integrated just for convenience). Not a deal breaker.
2. Ditto for an onboard DAC (USB capable). Again, we can use one externally, but for convenience it would be nice. Not a deal breaker because we are talking amplifiers here.

3. Here is where it gets interesting. Make the amplifier sound good, with lots of drive. Some old HK or NAD amplifiers with 20 or 40 watts sounded great!
4. Give it some heft from a build point of view.
5. Add VU meters = always cool. I love the old Style VU meters in the SX-1080 Pioneer amplifiers.
6. What is old is new again: be inspired by the golden age of gear from the 70's and in some cases the 80's: Substantial builds; illuminated (think Pioneer receivers); Brushed aluminium plain (but quality) construction (Sony, Pioneer, Harmon Kardon). One turn of a quality switch or knob and you have a winner product (if it sounds good).

You can build it to measure great; just make sure it sounds good for the masses.

 

[Mr. Swordfish]

If someone is sufficiently old school that they are in the market for a receiver it's not all that likely that they care whether the amplifier section is class A, A/B, D or whatever as long as it sounds good. Fosi doesn't make a receiver AFAIK, so those potential customers won't buy from Fosi. Maybe if you made a line of pre-amps that were marketed along with your amps you could hit this customer base, small though it might be.

I'm not a marketing guy, but this seems like a question with a pretty simple answer.

 

[Saponetto]

@Fosi Audio , follow this path and best it.
MOS-120

 

[EngineerNate]

I would guess most of this style of amp is sold to older folks without hifi knowledge who have a set of old speakers lying around and needed the minimum viable product to power them.

 

[Saponetto]

Not always true.

 

[EngineerNate]

Very little is always true.

The other place I see stuff like this is in businesses where someone needs the cheapest thing for ambient sound.

 

[mhardy6647]

Very little is always true.

That statement is partially true

ahem... sorry...

On topic. This is an old thread that's bobbed up again (like a corpse from a shipwreck? )... seeing it this morning got me to thinkin' about -- economics -- and (predictably) also thermodynamics.

A decent quality (work with me, now!) Class AB amplifier can be built with a very low parts count using (still) very inexpensive parts. Class D amp boards can certainly be built cheaply but they're still hella complicated (lots of itty bitty surface mount parts, and chokes, filters and suchlike to deal with out of AF band hash and noise) -- there's more to go wrong with a Class D amp board and it's far less likely to be repaired -- or to be feasiby repairable than a simple Class A or AB amplifier made with 'discrete' parts. I don't literally mean "discrete"; ICs are OK! -- but I do mean macroscopic parts and thus readily (and inexpensively) field/bench-level reparable and not disposable.

So... yeah... there's heat: The fashion even in most of the "value-priced" Class D components seems to be tiny, unventilated packaging and minimal heatsinking. Convective cooling (dude... vents -- not rocket science ) and a little airspace (even less rocket science-y)

... and then there's efficiency. The whole thing about the environmental impact of a thing is that one must evaluate this with a cradle to grave perspective... the impact of making, stocking, and shipping the parts and the impact of assembling, shipping, using, and disposing of the product.

"We" all tend to focus on the "using" piece -- and Class D amps are considerably more efficient than amps using A or AB topologies at near-maximum power output levels. Class D amps lose some of their advantage at idle and at low power output levels. How this nets out int he real world -- I don't know!I I have still not seen data showing that using the a Class D vs. a Class AB amplifier in the real world (e.g., playing music through actual loudspeakers at a finite SPL for a given period of time) has a marked overall advantage in terms of its energy consumption (watt-hours, i.e., power x time = energy). Maybe Class D amps really do have a real-world advantage, and I'd love to be pointed to some data!