Class D Vs Class I (Balanced Current Amplifier) - 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 September 2006, 02:33 AM   #1
diyAudio Member
 
Join Date: Sep 2006
Default Class D Vs Class I (Balanced Current Amplifier)

Was wondering if any electronics engineers could offer some technical opinions
on the subject.

Which topology is better, class-d, class-i or even class-h ?

From my limited experience in audio, I've learned that most arguments come
down to application, but since they're all a form of digital, perhaps there is
a "better" choice. When I say better, I'm thinking manufacturing costs,
reliability, sound quality and THD etc. Perhaps Class-I is just marketing hype?

I've been toying with the idea of contracting out some designs, hence the question. Application would be _big_ sound...pubs, clubs, events
and competition car audio. The dream is something along the lines of crown's
i-tech and JBL's 6KW beast http://www.caraudiomag.com/specialfe.../photo_03.html ....probably not quite so big, but along competition lines.
  Reply With Quote
Old 25th September 2006, 03:01 AM   #2
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Default Re: Class D Vs Class I (Balanced Current Amplifier)

Well,

Class-D is Classical Pulse Width Modulation switching amplifier...Its output consists of Mosfets in Pushpull manner and a series connected Inductor filter to retrieve the audio wave from the Pulsating signal through averaging effect of inductor.Efficiency is around 90-95%.....

Class-I is just another hyped version of Class-D but it uses two large inductors for storing energy as the both output mosfet conduct at same time, though absence of dead-time, but its high frequency response is not good one.....Its also Known as Balanced Current amplifier [BCA]...

Class-H is actually a Class-AB amplifier whose supply rails were switched from lower level to upper level in accordance with the output voltage required to get efficiency.....2 Tier Class-H is Efficient upto
65-75% with music signals


I have developed both Class-D and Class-H amplifiers......

regards,
K a n w a r
  Reply With Quote
Old 25th September 2006, 01:10 PM   #3
TOINO is offline TOINO  Portugal
diyAudio Member
 
TOINO's Avatar
 
Join Date: Oct 2004
Location: Coimbra
When I look for “class-I” schematics, the only thing I see is two Buck regulators bridge connected…
One positive the other negative, like class-B analog amplifier.

Could some body tell me if I need eyeglasses, please..?
  Reply With Quote
Old 25th September 2006, 05:15 PM   #4
diyAudio Member
 
Join Date: Apr 2005
Location: São Paulo
Where can I read more about Class-H ?

There is schematics ? websites???

regards,
João
  Reply With Quote
Old 25th September 2006, 05:49 PM   #5
TOINO is offline TOINO  Portugal
diyAudio Member
 
TOINO's Avatar
 
Join Date: Oct 2004
Location: Coimbra
Oi João...

http://www.qscaudio.com/support/tech...rt/schems1.htm
  Reply With Quote
Old 25th September 2006, 05:52 PM   #6
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Quote:
Originally posted by TOINO
When I look for “class-I” schematics, the only thing I see is two Buck regulators bridge connected…
One positive the other negative, like class-B analog amplifier.

Could some body tell me if I need eyeglasses, please..?
Hi TOINO,

www.crownaudio.com/pdf/amps/137234.pdf
www.crownaudio.com/pdf/amps/137331.pdf


Quote:
Originally posted by jmartins
Where can I read more about Class-H ?

There is schematics ? websites???

regards,
João
In mY Thread

The Class - H Amplifier

regards,
K a n w a r
  Reply With Quote
Old 25th September 2006, 06:30 PM   #7
diyAudio Member
 
Join Date: Sep 2006
Workhorse: thanks for the input, I remember you as ampman ...from a few
years back, glad to see you're still alive and kicking!

Perhaps drop me an email when you get a chance, design@rmsaudio.com. I
did try and email you, but the forum didn't allow it.
  Reply With Quote
Old 25th September 2006, 06:37 PM   #8
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Hi RMS,

Nice to see you too..........

email me at

info@workhorsetechnologiesindia.com


for any enquires....

It seems to me that you also changed your Identity as your registration is dated to 2006...and you say you know me from past few years

regards,
K a n w a r
  Reply With Quote
Old 25th September 2006, 06:50 PM   #9
TOINO is offline TOINO  Portugal
diyAudio Member
 
TOINO's Avatar
 
Join Date: Oct 2004
Location: Coimbra
Hi Workhorse

Yes I know all the Crown “pa-ta-ti-bla-bla”, but analysing the schematics: http://www.jblproservice.com/pdf/Ver...Schematics.pdf
Is just two Buck converters assembled like a class-AB output “linear” power amplifier.
On class-AB you have 1 power transistor for positive part of signal and another for negative.
Positive one could only source current to load=Class-I positive Buck converter.
Negative one could only sink current from load= Class-I negative Buck converter.
For my eyes, class-I looks like a switched class-AB counterpart in which the output transistors are Buck-converters.
Even the modulation scheme is in a way to simulate the linear class-AB amplifier.
  Reply With Quote
Old 26th September 2006, 03:16 AM   #10
diyAudio Member
 
Workhorse's Avatar
 
Join Date: Dec 2004
Hi TOINO,

Yes your right, but have you noticed one thing that the two mosfets switch at same time .......but the Pulse width changes according to the signal

Do you have RAM audio schematics....

regards,
K a n w a r
  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
Balanced tube preamp for class D power amps. jane Tubes / Valves 5 13th December 2006 07:41 AM
class B and AB idle current demons_wing Solid State 6 6th October 2004 05:14 AM
current sharing in class AB outputs hitsware Solid State 5 19th October 2003 05:02 PM
Balanced Class A pre amplifier insights macka Pass Labs 0 25th December 2001 08:17 AM


New To Site? Need Help?

All times are GMT. The time now is 06:46 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