Article on Philips prototype digital amp - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

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 2nd December 2003, 06:50 PM   #1
diyAudio Member
 
Join Date: Dec 2003
Location: Randers, Denmark
Default Article on Philips prototype digital amp

A few years ago (2-4) I read a very interesting article in a hi-fi magazine. It was one or two authors that visited an engineer from Philips. He had developed a digital amplifier (prototype), which worked with 8 different digital amplifiers in parallel per channel. It was fed directly with a DSD signal from a SACD machine. Is there anyone out there that can remember what magazine it's from?
  Reply With Quote
Old 3rd December 2003, 08:20 AM   #2
EDUM is offline EDUM  Netherlands
diyAudio Member
 
Join Date: Oct 2003
Location: Almere
There was an article in the German HiFi magazine "Stereoplay" in june 2002 (nr 6) . In this Testspecial "Die neuen Digitalamps-das Aus fuer unsere verstaerker" the Philips PPDSD system was discussed.

In that Philips kitchen a lot of beatiful things are cooking. Unfortunately most of it never gets to the market.
(I heard Philips electrostatic speakers driven by an optical isolated high voltage transistor amplifier!)

Ward
__________________
The vast number of parameters involved in human hearing make imperfect designs certain.
  Reply With Quote
Old 3rd December 2003, 08:46 AM   #3
diyAudio Member
 
Join Date: Dec 2003
Location: Randers, Denmark
Default Thanks

Quick reply I must say

Now I remember, unfortunately I have thrown all og my hifi magazines away last time i moved, so I don't have that issue anymore. If you (or others) could scan the article and attached it here (I donīt now if that is legal?), I would be a happy man.

Brian
  Reply With Quote
Old 3rd December 2003, 12:33 PM   #4
diyAudio Member
 
Join Date: Dec 2002
Location: Slovenia
Hi,

Some information is also here: http://www.classd.org/oem_products/p...hilips_dsl.htm and also authors own opinion about it http://audioholics.com/techtips/audi...mplifiers.html.

It really makes you wonder what is behind that 16 transistor UCD amplifier.

Best regards,

Jaka Racman
  Reply With Quote
Old 3rd December 2003, 01:34 PM   #5
diyAudio Member
 
Join Date: Dec 2003
Location: Randers, Denmark
Default Thanks again

This is a very fast answering forum. Very good links.

Brian
  Reply With Quote
Old 5th December 2003, 07:35 AM   #6
EDUM is offline EDUM  Netherlands
diyAudio Member
 
Join Date: Oct 2003
Location: Almere
Hello Kjeldsen,

I am sorry I can not help you on short notice with a scan, but may be your local libray has it in their magazine area.

Ward
__________________
The vast number of parameters involved in human hearing make imperfect designs certain.
  Reply With Quote
Old 5th December 2003, 12:25 PM   #7
diyAudio Member
 
lieven's Avatar
 
Join Date: Aug 2002
Location: Belgium
Default universal class d

seems something cooked with two tl3842 (or similar)a couple of mosfets (2sk2645 or similar) and a ?control circuit?

basic setup is the simpliest switching supply you can think of.



have article yet? if not I'll mail it. BTW search for Bruno Putzeys on internet, you'll find it.

just try this one:
http://www.semiconductors.philips.co.../TDA8924_1.pdf
  Reply With Quote
Old 5th December 2003, 12:27 PM   #8
diyAudio Member
 
lieven's Avatar
 
Join Date: Aug 2002
Location: Belgium
Default tda8924

it's a DGC : digital gainclone

use it straight or inversed, hehehe
  Reply With Quote
Old 5th December 2003, 01:36 PM   #9
diyAudio Member
 
lieven's Avatar
 
Join Date: Aug 2002
Location: Belgium
Bad for Nelson's Alcoa stock....

tda892X not for sale yet, only samples available
  Reply With Quote
Old 6th December 2003, 08:30 PM   #10
deandob is offline deandob  Australia
diyAudio Member
 
Join Date: Oct 2002
Location: Brisbane, Australia
Default Anyone trying the philips Class D implementation

Is anyone planning on trying the TDA8924?

Is it the UCD amplifier discussed on the classd.org site that got such a good wrap? Specs look reasonable (comparable to the competition) and the implementation looks to be easy. The UCD amp on classd.org mentions a zero feedback system with feedback (??) taken after the loop filter, but looking at the TDA8924 specs there is no feedback path after the filter so I guess its not the UDC design.

The other interesting thing about this chip is that it mentions high power supply ripple rejection, yet most class D implementations have very low or no (eg. Equibit) supply rejection.

Regards,
Dean
  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
Digital X-over Prototype blu_line Digital Source 5 8th May 2010 02:44 PM
Philips SCD2000 sacd player prototype ll0ll Digital Source 9 29th December 2009 09:44 PM
philips cd630 tda1541a. what about add a digital input? zigo3 Digital Source 9 3rd November 2007 01:55 PM
Philips CD304 Need pin-out digital-out retro-audio73 Digital Source 6 29th May 2006 08:22 PM
Looking for Discontinued Philips Part Digital filter SAA7220 P/B xorbitman Parts 0 19th July 2005 06:09 PM


New To Site? Need Help?

All times are GMT. The time now is 12:05 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright Đ1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2