When did class D start to not suck?

[Blumlein 88]

I also don't think the architecture is the issue, but what is an issue is the bad build quality of many, and the biggest issue is that IC's go fast out of production so repairing class D amps is a lot harder than repairing Class A or AB amps as parts are harder to find. And repairing an SMD board is also harder than through-hole components. But those are not limited to class D, those are general issues in modern electronics. It's less durable due to the way the systems are build physically, not due to the architecture of the amp.

And yes, i'm also aware of the advantages of IC's and SMD, they are cheaper to build, smaller, and take less natural resources. But they are not a free lunch...

Not free, but if a very powerful amp with good performance and 85% energy efficiency is available for $1500 and lasts ten years it isn't too bad. The alternative for similar power might cost 2x or 4x as much and might last longer, but even AB designs get iffy past 20 years with some caps they have. Repair might be easier or just buy what is probably by then an even better class D amp for cheap and go another 10 years.

 

[mhardy6647]

There is nothing in the architecture of class D that makes it more likely to fail. If anything, due to the higher efficiencies and therefore potentially lower temperatures involved it should (if designed well) be more robust.

High parts count and density.

Not free, but if a very powerful amp with good performance and 85% energy efficiency is available for $1500 and lasts ten years it isn't too bad.

I dunno -- to me, lasts 10 years is nigh-on equivalent to disposable.
Plenty of 60-plus year old stuff here that works fine (indeed, better than do I -- of similar vintage ).

 

[Waxx]

Not free, but if a very powerful amp with good performance and 85% energy efficiency is available for $1500 and lasts ten years it isn't too bad. The alternative for similar power might cost 2x or 4x as much and might last longer, but even AB designs get iffy past 20 years with some caps they have. Repair might be easier or just buy what is probably by then an even better class D amp for cheap and go another 10 years.

I think 10 years is not enough, it should last longer and be repairable. I don't like the throw away economy of the last decades, things should last. And i'm surely not the only one who thinks like that. Here in the EU there are even laws in the making that will demand that electronic devices last a certain time or get taxed extra (and severly extra) just because of that short lifespan of this. It's economic and ecologic a disaster.

 

[antcollinet]

High parts count and density.

Again - that is not architecture, and can apply to any amp class. Please read my preceding 3 or 4 posts to understand why.

 

[Blumlein 88]

I think 10 years is not enough, it should last longer and be repairable. I don't like the throw away economy of the last decades, things should last. And i'm surely not the only one who thinks like that. Here in the EU there are even laws in the making that will demand that electronic devices last a certain time or get taxed extra (and severly extra) just because of that short lifespan of this. It's economic and ecologic a disaster.

All sounds nice, but I think your living a time that has passed. If a 30 year amp uses twice the resources being made and burns 3 time the electricity for same use as 3 ten year amps, you haven't done anything good for the environment or the economy. I also don't know that class D will die after 10 years, but perhaps it may average that or just the fact it will be unrepairable at that point. I'm not so sure they won't last just as long as good ones run much cooler.

I wonder about those EU regs. I knew they had rules about stuff being recyclable. How can you tax longevity?

 

[valerianf]

"Do you think other class amps do not use similarly cheap components? "
Please read the post of @olegtern
He cannot get is >2 years old class D amp without changing the amp module.
For a $2 bad quality chinese electrolytic capacitor you have to pay a $××× amp module.

And that fact is related to the current class D amp module technology:
1) the low quality chinese capacitors are not very reliable.
2) the chinese capacitors cannot be sourced out of China.
3) the pcb is so dense and the capacitors are glued thus making the board very if not impossible to repair.
4) without any schematic and real knowledge of the class D IC behavior it is very difficile to make a proper diagnostic.

Class AB amps are easier to repair and most of the failure are coming from known functional blocks.

Similar to @Olegetern I got a small class D amp (a Yamaha WXA 50) that I enjoy.
It is 3 years old and still working properly.
I rely on Yamaha service department in case of problem.
But I worry that the same miss-adventure will happen to me one day.

 

[Tangband]

I would say that a good implementation of tpa 3118 was the first time when class D sounded really good at sensible levels and almost for no cost at all . This left the field open for making active, good sounding speakers with active crossovers .

The Genelec 8030c is a good example of this .

This Texas instrument chip came out 2012. My own subjective listening tests between the class A/B chipamp LM 3886 and tpa 3118 in two different amplifiers showed that LM 3886 sounded worse.

https://www.ti.com/lit/ds/symlink/tpa3118d2.pdf?ts=1670088080125&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTPA3118D2

The Allo amplifier also have dual tpa 3118 chips and was reviewed by Amirm :

Allo Volt+ D Amplifier Review

This is a review and detailed measurements of the Allo Volt+ D class D amplifier. It was kindly sent to me by a member and costs US $129 in this "dual mono" configuration with stepped attenuator. I am not a big fan of these clear cases but in this case, pun intended, it works! Hard to take...

www.audiosciencereview.com

After 2012, there are many newer integrated power amps that have come out, notably the tpa 3255 and tpa 3251. The latter was used in Topping pa5.

Topping PA5 Review (Amplifier)

This is a review and detailed measurements of the Topping PA5 stereo desktop amplifier. It was sent to me by the company and costs US $349. PA5 enclosure looks like their standard DACs and such: Hard to imagine that an amplifier can fit in the same size but here we are. There are large...

www.audiosciencereview.com

 

[olegtern]

Please read the post of @olegtern
He cannot get is >2 years old class D amp without changing the amp module.
For a $2 bad quality chinese electrolytic capacitor you have to pay a $××× amp module.

I will clarify that the breakdown was not related to bad capacitors (I understand that you do not mean it, but just so that there is no misunderstanding about this case), there were no obvious damages, but the amplifier stopped turning on. Something happened to the control "brains". I think that in the case of damaged capacitors, repair would be easier and similar to repairing any other amplifier. In which, by the way, "bad chinese capacitors" have also been installed for many years.

It seems to me that the only way not to worry about this is to buy equipment that, in the event of a breakdown, you can replace within a month without a hole in the budget. Fortunately, class D amplifiers provide such an opportunity with excellent value for money.

 

[dorakeg]

I just saw this thread. I think Hypex was one of the first company that makes high-end Class D stuff. So I guess around 20yrs ago?

I remember MBL was using Hypex back then. Very very expensive.

 

[valerianf]

@olegtern Thank you for the update about the symtoms of you dysfunctional class D amp.
In your case, as the amp is not powering up any more, it could be multiple issues: the on/off button is fautly, a connector is faulty, the PSU controller is faulty, the power supply itself is faulty...
We could find the same root cause on any class AB amp.
Any good repair shop would investigate the issue and fix it.
But in your case it is a class D amp with a "blackbox" OEM module.
Thus the repair center will bill a brand new oem module! Easy $xxx.

I really think that my next buy will be a class AB amp, because of the maintenance issues.

 

[olegtern]

I really think that my next buy will be a class AB amp, because of the maintenance issues.

It's a matter of choice.

In my opinion, a modern audio system consists of several key components: streamer -> DSP (ideally with SUB management, for many, room correction is desirable) -> DAC -> volume control/preamp -> amp.

Whatever we choose, some of this stuff will have difficult to repair modules. I have experience with repairing of an expensive DAC, and everything is no easier there than with amplifiers (fortunately, I got excellent service even for post-warranty equipment). Besides the sum of the components costs a lot, and requires commutation, which creates the risk of ground loops, etc.

As an alternative, we have all-in-one combos at an affordable price (considering the sum of the parts). They have all these features, are comfortable and, most importantly, already sound very good. There is a service period, and they can be replaced without much pain in case of death. In addition, in a few years, something even more functional and attractive will appear or the sound will improve (for example, under the pressure of measurements here on ASR). My choice today is here.

One more option — all-in-one active speakers. And there are very interesting products here, which cost much but offer more than the sum of the parts.

I'm not really worried about the class of amplifiers inside, as long as it sounds good, but it is obvious that class D dominates in such devices.

 

[Mart68]

One more option — all-in-one active speakers. And there are very interesting products here, which cost much but offer more than the sum of the parts.

I'm not really worried about the class of amplifiers inside, as long as it sounds good, but it is obvious that class D dominates in such devices.

This, though, was the main reason I did not get Kii3. Right now if something fails in my system - source, DAC, amp, speaker - I can immediately swap in a replacement and carry on.

If something goes bad inside an active speaker, I can't do that. I have to ship it somewhere to hopefully get it fixed. Okay so the Kii has better bass. But is it worth that potential issue?

 

[olegtern]

But is it worth that potential issue?

It is unlikely that there is a universal answer here, everyone decides. I think, if you cannot replace a breakdown without a significant hole in the budget, this can be a very painful problem.

I really don't like being left without music in the event of a breakdown. For such a case, I have a stock of different components and modules to start the system at any time. And the amp I use doesn't exceed my monthly budget even in a bad month. Unfortunately, even this does not guarantee complete security, so a little zen and a memory that nothing lasts forever can't hurt!

 

[Mart68]

It is unlikely that there is a universal answer here, everyone decides. I think, if you cannot replace a breakdown without a significant hole in the budget, this can be a very painful problem.

I really don't like being left without music in the event of a breakdown. For such a case, I have a stock of different components and modules to start the system at any time. And the amp I use doesn't exceed my monthly budget even in a bad month. Unfortunately, even this does not guarantee complete security, so a little zen and a memory that nothing lasts forever can't hurt!

If I were sure they would last at least 20 years without fault there would be no problem since in that case I will quite probably fail before they do But there's no such guarantee.

Right now, like you, I have replacement equipment that can just be slotted in.

 

[Waxx]

It is unlikely that there is a universal answer here, everyone decides. I think, if you cannot replace a breakdown without a significant hole in the budget, this can be a very painful problem.

I really don't like being left without music in the event of a breakdown. For such a case, I have a stock of different components and modules to start the system at any time. And the amp I use doesn't exceed my monthly budget even in a bad month. Unfortunately, even this does not guarantee complete security, so a little zen and a memory that nothing lasts forever can't hurt!

I got lots of stuff, mostly very inexpensive, and when the official price was expensive, i got it cheap one or the other way. It moves arround in my house all the time mostly and i got spares in stock all the time. Most of the time i got 4 or 5 systems working in different parts of my house (office, living/music room, kitchen, workshop, bedroom). As i repair and restore stuff (mainly speakers) and sell and buy much moves in an out also, at least before covid. Now it's calmer.

Active speakers are tricky on this, because the electronics die way faster than the speaker itself. If it's easy to repair, with stock parts that are arround in big numbers (like most Neumann speakers are) it's not a big risk. But when they use special or custom parts, when the electronics die the speaker becomes worthless.

 

[Adi777]

Okay so the Kii has better bass.

Why better?

 

[Mart68]

Why better?

cleaner, tighter, stops and starts faster, goes deeper, has more definition (than my current speakers to which I'm comparing).

 

[Adi777]

cleaner, tighter, stops and starts faster, goes deeper, has more definition (than my current speakers to which I'm comparing).

Which speakers?

 

[Mart68]

Which speakers?

JM Lab Focal Electra 926

 

[Gregss]

Hello,

Personally, I have gone with class D as the efficiency and regard for our environment matter to me. Otherwise I would say go with whatever class amp you like, just get top quality (not price) equipment and you will very likely be happy for a long time. IMHO. ( Cheaply made junk is bad in any class of equipment. )

Regards,
Greg