The Future of Class D.

[TerryG]

I was thinking, in five (or perhaps ten) years from now what will we talking about on this forum? At the very least ten years from now class D will have taken over the amplifier market, especially home theater, and then mainstream audio (including all sorts of battery operated audio electroinics), and finally a large share of hi-end. But probably the first market that class D will get a firm foothold is the pro sound market. Very shortly this forum will change drastically, as we will have more quality class D amplifiers than we can shake a stick at, it is bound to happen. We will shift from our focus on just making them, to how we can make them better, how we can take off the shelf high powered pro sound amps, and make them sound ever so sweet. Low noise and low distortion will not be the focus as much as more refined approaches to the subtle sonic sweetness we can acheive.

But until then this world will owe a lot to the pioneers of class D.

One thing though I wonder. The TacT Millinium came out in 99-2000, and for all its raved reviews, five or more years later we are just starting to see class D catch on. WHAT IS TAKING SO LONG!!!

Terry

[rpapps]

The first commercial class d amplifier, the X-10, was made by Sinclair Radionics back in 1964 so its evolution is even longer than you thought.

[classd4sure]

.... and the theory existed since before 1954. Terry you don't realize how refined class d is these days.

I wouldn't expect more "refined" amps than you can shake a stick at either, there'll be the top few and the rest will fall to the side. Refined class d is not so trivial that everyone will be doing it.

Where they will first rule is where they already do, small hand held/portable and battery operated devices.... cell phones etc.

Do a little research on the topic (worth it, I think) and you'll know exactly why it took so long to get where it is now.

Regards,
Chris

[TerryG]

RESEARCH!! I have been doing research for the last two years. I don't understand why the learning curve is the way it is. If what you gents are saying is correct we have a technology that is eluding us big time. Here you have a manufacture of class D amps such as Hypex and how many production amplifiers are using them. Why is it taking so long for this technology to get a foothold. Saves energy, sounds better, smaller, but takes engineers that are technically savey enough to do the proper PCB layout. I don't get it, is this technology really that difficult to make work?

Terry

[classd4sure]

Originally posted by TerryG
RESEARCH!! I have been doing research for the last two years. I don't understand why the learning curve is the way it is. If what you gents are saying is correct we have a technology that is eluding us big time. Here you have a manufacture of class D amps such as Hypex and how many production amplifiers are using them. Why is it taking so long for this technology to get a foothold. Saves energy, sounds better, smaller, but takes engineers that are technically savey enough to do the proper PCB layout. I don't get it, is this technology really that difficult to make work?

Terry

Two years? Well the answer is simply because the components that could handle the job never existed until recently. At first they weren't even possible, and when they were possible, there wasn't a great enough demand for them to start producing and refining them to the level high fidelity audio requires. With the take off of cell phones and other such devices finally there was enough of a market for them to make it happen, and so, here we are today!

Then, you require people with a vision, and a deep understanding who can put something together that not only switches nicely but is worth listening to.

Further to that as you likely realize class d is not a simple amplifier. It's a tight blend of many fields, from power electronics to analog to digital to magnetics and I'm sure the list goes on.

There's also no such thing as a good book on it, much of the information available online is misinformed or just plain wrong... well, you get the idea now right? I just saved you two more years worth of research

Regards,
Chris

[TerryG]

Originally posted by classd4sure

Then, you require people with a vision,

This to me seems to be it in a nutshell. There is just no other reason for this technology to not be making faster progress. When your vision is simply money then snake oil is a better way of making money than something a little difficult to come by.

Someone should write a book.

Terry

[classd4sure]

Originally posted by TerryG


This to me seems to be it in a nutshell. There is just no other reason for this technology to not be making faster progress. When your vision is simply money then snake oil is a better way of making money than something a little difficult to come by.

Someone should write a book.

Terry

Someone should, but few are qualified and those who are, are in deep competition and perhaps haven't yet made their fortunes.

Others with visions perhaps lack understanding/financial backing, take your pick there's every reason it hasn't developed faster.

For instance this forum has become a bit of a gold mine and will continue to grow in that respect, I hope. Most are too lazy to read it and instead just keep asking the same basic questions.

Do you really want to know where this forum will be ten years from now? The good threads will be burried by the same tired questions that keep getting repeated over and over.

You've researched this two years you said, built anything yet?

I've been researching for around six years, where's my design?

How many years of that research was spent barking up the wrong tree, caught by a mass wave of marketing BS, true digital and other such garble.

How long did it take you to learn how to switch a mosfet half decently? Can you?

Do you know about Mueta? Where's their product? They've changed the face of class d, at least according to their website for the past four years or so. Heard one yet?

Clearly they've got the vision, the financial backing, where's the amp?

Nah, things are more complicated, as always.

Class d is certainly an area where the more you learn the less you know. To me, that's it for you right there, in a nutshell.

Regards,
Chris

[destroyer X]

For a while, my conclusions are: (they can change...of course!)

Class D works fine when speaker is the factory one.... so... systems, Mini Systems and Home theater can sound great.

My Class D unit do not produce good sound with any speaker....with some of them sound good, with others sounds awfull.

My unit can reproduce clear 20 hertz, but i could not listen 16 Khz, when i can using analogue designs.

I cannot feel good sound stage....sound really comes from speakers.... dimension is strange, and also acoustic positioning of speakers are critical.

Produces enormous bass...but speaker cone seems not move!...of course it moves...but there are not others movements than the signal.

Compared together....blind testing...you do not know the one is class D and the one is analogue.... outside of your home...other place and other music.... someone adjust both to same "audible" volume.... and them you compare.

No doubts!...you gonna shot the analogue one!

Despite of that i am doing a lot of analogic amplifiers.... having my fun, my friends, the main ones, use to listen to normal amplifiers, also Solid State forum is rich of Do it yourself schematics...when here sometimes appear one or two that you can construct.... not to be lonely, i construt analogue...but to listen...hehe...only my class D.

Hey!...do not talk Solid State guys..... they will never accept that... something very strange that resistance.

This may mean give up of their own life Hystory..... to erase all they learn and to start to buy Chips (some black boxes)... their fun will finish....their friends will seems silly...so....they cannot see that...unfortunattelly.

regards,

Carlos

[TerryG]

Chris & Carlos,

You both make some good points, how valid some of them are is the real question, or how valid should they be. Thanks for the info on Mueta (I hadn't come acrossed them yet), although like a lot of other companies in this field they seem to be selling hype rather than a good product that can stand on its own two feet. I don't get why SS guys are resistant to class D, that doesn't make sense, but when change is in the air you will always find people that are resistant to change, thats just life.

We could blame this all on the MOSFETs were not availible to produce good class D amps, but that doesn't account for the lack of vision of the big companies that produce their own parts. I would really just like to know what the big hang up is. From what you guys are saying it sounds like it is just a bunch of little petty excuses by manufactures.

You give me a good analog/class D comparison I and will probably be able to tell which one is which, but that doesn't matter. What I really will be looking for is which one sounds better. Just because it is class D doesn't mean it will automatically sound better, but the potential is there.

I look at these schematics and wow they have so many less parts that a typical SS amplifier. I listen and they sound better than 90% of what is on the market. So it is getting harder and harder to find a REAL reason why this technology hasn't taken off.

Terry

[classd4sure]

Originally posted by TerryG
Chris & Carlos,

You both make some good points, how valid some of them are is the real question, or how valid should they be. Thanks for the info on Mueta (I hadn't come acrossed them yet), although like a lot of other companies in this field they seem to be selling hype rather than a good product that can stand on its own two feet. I don't get why SS guys are resistant to class D, that doesn't make sense, but when change is in the air you will always find people that are resistant to change, thats just life.

We could blame this all on the MOSFETs were not availible to produce good class D amps, but that doesn't account for the lack of vision of the big companies that produce their own parts. I would really just like to know what the big hang up is. From what you guys are saying it sounds like it is just a bunch of little petty excuses by manufactures.

You give me a good analog/class D comparison I and will probably be able to tell which one is which, but that doesn't matter. What I really will be looking for is which one sounds better. Just because it is class D doesn't mean it will automatically sound better, but the potential is there.

I look at these schematics and wow they have so many less parts that a typical SS amplifier. I listen and they sound better than 90% of what is on the market. So it is getting harder and harder to find a REAL reason why this technology hasn't taken off.

Terry

So what makes you think these big companies have the talent to pull off a smart design?

I think Sanyo is making an IC out of ICEpower, what's that tell you?

The MOSFET's wasn't just an excuse, it was reality until about oooooh say 4 or 5 years ago. That didnt' stop everyone from patenting everything they could. Try and come up with an original design that isn't covered by some patent already, you'll see it's not so easy.

As far as Mueta their idea is fairly brilliant, but they aren't actually selling anything.

I look forward to seeing your amp one day Git on it!

Regards,
Chris