What level of maturity has class D reached in the commercial industry?? - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 25th April 2013, 09:12 PM   #1
diyAudio Member
 
Reactance's Avatar
 
Join Date: Jun 2005
Location: Cape Town
Default What level of maturity has class D reached in the commercial industry??

Itís been a few years now that class - D audio has been commercially available in the wild, itís of course had its criticism from many critics like its predecessors classification A and AB, it of course remains unbeaten in efficiency and size.

I'm curious to know the level of maturity the standard has adopted, are we seeing a wave of audio units using this technology or are companies still using AB in medium to high end products and shying away from this tech as a result of the complexity and myth it surrounds around EMI.
__________________
Thereís nothing worse than the smell of burned output transistors!!
  Reply With Quote
Old 25th April 2013, 10:16 PM   #2
Banned
 
Join Date: Jan 2005
Early class d was quite sad, but the new stuff like UcD and NCore are now rivaling the best class A and class AB amplifiers out there.

Even my crusty mono UcD prototype impressed a friend of mine that is an audiophile owning expensive high end equipment, and that on some crusty old "white van scam" speakers.
Hypex got it right, proving that UcD was the way to go.
  Reply With Quote
Old 25th April 2013, 10:44 PM   #3
diyAudio Member
 
Join Date: Dec 2003
Location: Munich
It is clearly coming.
The CD in the 80s was a new technology, with many short comings - but good enough for the mass of listeners.
Ease of handling was the key for success, not the sound quality.

Despite my personal opinion that most classD implementations of the year 2013 are not deserving the name HiFi - also such average implementations are already good enough to win a growing amount of people.
Size and power density is sexy for the customers.
Already at medium power levels (level decreasing further) the material costs are significantly below class AB, which is sexy for the manufacturers.
Energy efficiency is another selling point.
Only R&D costs are still high, partially also because of EMI.
But that's just an initial barrier, which already has been taken by multiple companies. Efforts for derivates will decrease with experience.
It is a winning technology and also sound quality will improve further so that many companies will be able to satisfy also demanding High End customers.
I would also expect a slow shift from analogue modulators to digital solutions for modulator and feedback.
  Reply With Quote
Old 25th April 2013, 11:14 PM   #4
diyAudio Member
 
KatieandDad's Avatar
 
Join Date: Nov 2011
Location: UK
From my experiments and what I read about Class D, there are still some serious shortcomings with the ability of Class D amps to drive complex loads. A good Class D amp with the correctly tailored load will sound superb but therein lies the problem. Class A and Class A/B are more forgiving and will drive less than perfect loads almost with impunity.
  Reply With Quote
Old 25th April 2013, 11:35 PM   #5
diyAudio Member
 
nigelwright7557's Avatar
 
Join Date: Apr 2008
Location: Carlisle, England
Quote:
Originally Posted by KatieandDad View Post
Class A and Class A/B are more forgiving and will drive less than perfect loads almost with impunity.
I cant say I have had any problems driving any sort of load.
The only time class d goes wrong is if the speaker is totally disconnected and the irs2092 goes to +17VDC.

I haver driven from 18 inch subs up to tweeters and it sounds great.

However I agree class AB are more forgiving than class d but from a design point of view. Most people can design a class AB amp and build it up with few problems. Class D layout is vitally important, you cant hang output transistors on 6 inches of wires and expect it to work. Decoupling and component layout is critical. Also getting the output filter right is vital to a good sound.

It took me 3 pcb revisions to get a class D amp working. But I learned a lot from the experience about class d and its cousin SMPS.
  Reply With Quote
Old 26th April 2013, 07:03 AM   #6
diyAudio Member
 
Saturnus's Avatar
 
Join Date: Jun 2005
Location: Copenhagen, Denmark
Quote:
Originally Posted by KatieandDad View Post
From my experiments and what I read about Class D, there are still some serious shortcomings with the ability of Class D amps to drive complex loads.
No so much an amplifier problem at all though. It's a speaker design and application problem. Complex loads almost only happens with passively filtered speakers. With class D there's little reason to passively filter speakers at all as active filters and more amp channels, each suited for the specific driver in question, or even digital filters if the signal is inherently digital which it most often is.

The only "problem" is that it inherently incurs a paradigm shift towards active speakers with amplifiers optimized for the exact speakers used, and very likely also built-in compensation algorithms which inherent sounds suspect to "audio old timers".
  Reply With Quote
Old 26th April 2013, 05:38 PM   #7
diyAudio Member
 
Join Date: Dec 2003
Location: Munich
Quote:
Originally Posted by KatieandDad View Post
From my experiments and what I read about Class D, there are still some serious shortcomings with the ability of Class D amps to drive complex loads. A good Class D amp with the correctly tailored load will sound superb but therein lies the problem. Class A and Class A/B are more forgiving and will drive less than perfect loads almost with impunity.
Tell me your desired bunch of different complex RLC loads and we can go for measurements on my open design here in the forum .
You will see that load variations are handled with a smile.

The often mentioned strong dependency on the load is true in designs, which are 5-10 years behind state of the art.
...but of course still popular in the market - one of the reasons, why I say most of the implementations today are do not really serve High Fidelity.
  Reply With Quote
Old 26th April 2013, 11:47 PM   #8
diyAudio Member
 
Soldermizer's Avatar
 
Join Date: Feb 2012
Location: Tamper, FL, USA
In another posting, I read that Linkwitz is finally considering DSP crossovers as worthy. And this is from a very old school EE (?) At least I consider hand-building analog active x-overs hard core, and way above my pay grade.

On the other hand, there are odd balls like me that enjoy the best of (already built!) high tech -- in my case, a Behringer class D, and active eq, and the crossover free ancient Bose 901s (ca. 1970s).
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Industry Level Drill Bits for DIY siliconray Siliconray Online Electronics Store 0 7th March 2012 12:52 AM
Whats the industry standard height for driver/ear level? Bill poster Full Range 9 12th May 2010 08:23 PM
Any new commercial Class-D amps available? iwamusr Class D 0 18th December 2007 07:37 PM
Some measurement of commercial class D banana Class D 33 3rd September 2006 01:02 PM
Does anybody work in the industry/related industry? eRiCdWoNg Everything Else 5 25th August 2004 08:38 AM


New To Site? Need Help?

All times are GMT. The time now is 02:06 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2