In theory, Class D amplifiers are far better than class AB, But even today if you check the market Class AB amplifiers are at the top when it comes to sales. And the reason is users say there is not much of a difference between the sound of AB or Class D active speakers so why should they pay any premium for D. Your opinions on that?
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I'd rather go with the argument that they're 1) cheaper (overall at least, not just / necessarily the amplifier chips themselves), and 2) easier to implement.
I've seen LM3886's in several studio monitors (Tannoy, KRK, Yamaha, you name it). What do you need for those? A couple resistors, a couple capacitors and that's it. And they're under 4$ a piece in bulk.
For class-D amps, it's a bit more of a headache, even though prices for the chips themselves are comparable, or even less. First of all, very few are (still) available in through-hole packages, so that would need some "new" design practices, to some extent. Then you need output inductors and filter caps. Then, at least in theory, you'd need low-ESR caps for the amp section, which are more pricey than your bog-standard general-purpose 85C caps. Then you have to worry about the EMI hash getting into the line-level sections. Then there's the EMI testing and certification, which might involve one or two or several revisions / redesigns...
It's a bit of a Pandora's Box, almost.
"Class AB amplifiers are at the top when it comes to sales" - ok, but you might also wanna check the prices of the best-sellers then
I'm willing to bet they're probably not from the 4-5 digit price ranges...
I've seen LM3886's in several studio monitors (Tannoy, KRK, Yamaha, you name it). What do you need for those? A couple resistors, a couple capacitors and that's it. And they're under 4$ a piece in bulk.
For class-D amps, it's a bit more of a headache, even though prices for the chips themselves are comparable, or even less. First of all, very few are (still) available in through-hole packages, so that would need some "new" design practices, to some extent. Then you need output inductors and filter caps. Then, at least in theory, you'd need low-ESR caps for the amp section, which are more pricey than your bog-standard general-purpose 85C caps. Then you have to worry about the EMI hash getting into the line-level sections. Then there's the EMI testing and certification, which might involve one or two or several revisions / redesigns...
It's a bit of a Pandora's Box, almost.
"Class AB amplifiers are at the top when it comes to sales" - ok, but you might also wanna check the prices of the best-sellers then
I'm willing to bet they're probably not from the 4-5 digit price ranges...
I think EMI certifications are probably the biggest cause for concern. Something like the TPA3118 require very few supporting components and, when inside an active loudspeaker, don't even need output inductors either.
The highest performance class D amps (TPA325/4x) are another level of complexity though, but one thing to keep in mind are the engineers designing the speakers. You'd figure that they'd jump at the chance to use some of the better class D chips, but if they've been successfully using LM3886s for years/decades they might just prefer to stay with what they know.
Plus there is a stigma vs class D amps too.
The highest performance class D amps (TPA325/4x) are another level of complexity though, but one thing to keep in mind are the engineers designing the speakers. You'd figure that they'd jump at the chance to use some of the better class D chips, but if they've been successfully using LM3886s for years/decades they might just prefer to stay with what they know.
Plus there is a stigma vs class D amps too.
Interestingly enough, at least at Thomann, the cheapest class-D amp-equipped active monitors seem to be the JBL LSR305's (around 100-odd euros... a piece, i guess?).
I recalled i had read of Adam monitors using class-D amps, a while ago. Their cheapest one (170eu) seemingly does, and their more upmarket ones may well, too.
I recalled i had read of Adam monitors using class-D amps, a while ago. Their cheapest one (170eu) seemingly does, and their more upmarket ones may well, too.
One reason might be economy of scale, so it takes time for a new product to grow and establish itself. And also the size of market and engineers. if you see computers we have a long way. But in audio growth is quite slow. Ideally, by that rate, we should be having 500-watt speakers in the palm of our hands.
Who says so?
Old established technology vs. new one. That alone justifies it.
You are pulling that out of the blue.
And if anything, the "perception" is the opposite.
Who does?
You are throwing a lot of blanket statements with no hard data to back them.
And some even contrary to "common knowledge".
electrically class D is superior, but many still think class A or AB are sounding way better than class D. That's why that principle is used in most higher end amps. I also prefer class A or AB altough i have to admit that class D is getting better fast. Class A or AB also have an less complex layout but is more picky on components to sound good.
But at the end, if it sounds good it sounds good, whatever the class is... For me that is class A (SE) or class AB (PP) tube amps, wich is on electric level a totally inferior system to solid state, but i love the sound way more...
But at the end, if it sounds good it sounds good, whatever the class is... For me that is class A (SE) or class AB (PP) tube amps, wich is on electric level a totally inferior system to solid state, but i love the sound way more...
Also I will oppose the general statement ¨Class D amplifiers are far better than class AB". This has been debated among audiophiles on this forum for years.
Class D offers a better efficiency (less heating, not none) but has potential issues with noise emission and is a rather new technology (in production).
Class AB is an established technology with good sound, little noise emission but first of all available at a very attractive price (few components if based on an IC) and low risk in large scale sales because the technology is so well known. Also, class AB offers a better damping factor, if this is seen as important.
Thus, two technologies that are comparable in an active speaker.
How do large scale producers of consumer electronics think: PRICE.
Sales price minus production costs.
How do ordinary consumers prioritize: 1) purchase price, 2) presentation (physical outline) and 3) sound, unless the competitors sound really bad.
So, both large scale producers and ordinary customers agree on price as the most important factor. For the producers in order to earn profits, for the customers in order to make the household budget stick.
Most customers buy without A<>B tests, eventually directly on the Internet. As long as there are no overwhelming differences, one is as good as the other.
So, the producers take the safe way and use a cheap technology they know and will not bring new risks (what if we have sold 100000 units and there is a design flaw?). Cheap(er) production costs means better earning margins. The producers are happy and so are the customers.
You girls and guys, on this forum, are intellectually very interesting but you do not think like the ordinary consumer.
When class D becomes a known and risk-free technology, we will see such on the consumer market if the implementation costs are not much different than for (comparable) class AB. Also, remember that while we can produce much better amplifiers today at a low cost than 25 years ago, the human physiology (hearing) has not changed much and we need training to hear if it is a 0.1% THD amplifier or a 0.001% THD amplifier. To most persons, both sound just fine.
TI has made new TPA32xx chips that are impressive spec. wise. But, can TI sell them large scale? If the price remains high, the producers will remain with TPA3116D2/TPA3118, TDA8932, various STMicroelectronics versions (TDA7498 for instance) simply because the customers do in general not demand more.
I believe the next technology "jump" is when all audio signal handling is fully digital. Not because it will sound fantastically much better but because such systems are very flexible in which features you choose to implement (firmware wise). More gadgets for the customers and standard hardware for the producers -> low production costs.
Class D offers a better efficiency (less heating, not none) but has potential issues with noise emission and is a rather new technology (in production).
Class AB is an established technology with good sound, little noise emission but first of all available at a very attractive price (few components if based on an IC) and low risk in large scale sales because the technology is so well known. Also, class AB offers a better damping factor, if this is seen as important.
Thus, two technologies that are comparable in an active speaker.
How do large scale producers of consumer electronics think: PRICE.
Sales price minus production costs.
How do ordinary consumers prioritize: 1) purchase price, 2) presentation (physical outline) and 3) sound, unless the competitors sound really bad.
So, both large scale producers and ordinary customers agree on price as the most important factor. For the producers in order to earn profits, for the customers in order to make the household budget stick.
Most customers buy without A<>B tests, eventually directly on the Internet. As long as there are no overwhelming differences, one is as good as the other.
So, the producers take the safe way and use a cheap technology they know and will not bring new risks (what if we have sold 100000 units and there is a design flaw?). Cheap(er) production costs means better earning margins. The producers are happy and so are the customers.
You girls and guys, on this forum, are intellectually very interesting but you do not think like the ordinary consumer.
When class D becomes a known and risk-free technology, we will see such on the consumer market if the implementation costs are not much different than for (comparable) class AB. Also, remember that while we can produce much better amplifiers today at a low cost than 25 years ago, the human physiology (hearing) has not changed much and we need training to hear if it is a 0.1% THD amplifier or a 0.001% THD amplifier. To most persons, both sound just fine.
TI has made new TPA32xx chips that are impressive spec. wise. But, can TI sell them large scale? If the price remains high, the producers will remain with TPA3116D2/TPA3118, TDA8932, various STMicroelectronics versions (TDA7498 for instance) simply because the customers do in general not demand more.
I believe the next technology "jump" is when all audio signal handling is fully digital. Not because it will sound fantastically much better but because such systems are very flexible in which features you choose to implement (firmware wise). More gadgets for the customers and standard hardware for the producers -> low production costs.
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These active speakers are class-d and get very good review. 24v input so with a boost converter + battery + extra anti bash protection ya got portable speakers. they even have a mode where the main speaker with amp can be in mono mode for portable single speaker .
Vanatoo Transparent Zero Review
I find these quite interesting. I’ve avoided active speakers cus then tend to not include the best amps and would not know what to get, but after the pains of my diy amps box ups, this looks most attractive in its ready to go with portable potential.
. Vanatoo Transparent Zero Review
I find these quite interesting. I’ve avoided active speakers cus then tend to not include the best amps and would not know what to get, but after the pains of my diy amps box ups, this looks most attractive in its ready to go with portable potential.
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Need to understand that those Class rather B than Class AB or let's call it Class aB. The amp with 100mA bias for 50W, it is Class AB, I agree, but 5-20mA, sorry, no. So for the 10-40W range Class aB VS Class D:
1) cheaper
2) if not cheaper then a better performer. To get S/N -120db and THD = .001% across full audio band is a pretty much trivial task for a discrete Class aB
3) no special requirements regarding PCB layout, and EMI, Don't forget about millions chinese "engineers" with zero knowledge about the topic
4) That's funny but Class D running usually even hotter than Class aB. At least during typical music listening. So the efficiency, that's the single undisputable advantage of ClassD, doesn't look serious argument.
Class D is a king for >100W amps, or ok, for less than 100W but for a compact design, where is Class B lose automatically.
1) cheaper
2) if not cheaper then a better performer. To get S/N -120db and THD = .001% across full audio band is a pretty much trivial task for a discrete Class aB
3) no special requirements regarding PCB layout, and EMI, Don't forget about millions chinese "engineers" with zero knowledge about the topic
4) That's funny but Class D running usually even hotter than Class aB. At least during typical music listening. So the efficiency, that's the single undisputable advantage of ClassD, doesn't look serious argument.
Class D is a king for >100W amps, or ok, for less than 100W but for a compact design, where is Class B lose automatically.
Well, at least according to Douglas Self, the emitter-follower output stages do indeed need 50-100mA idle bias for proper class-B operation, but complementary-feedback pair ones only need about 1/10th of that.
Distortion In Power Amplifiers - Home Warranty Appliances
Distortion In Power Amplifiers - Home Warranty Appliances
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