hypex ncore - Page 62 - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Vendor's Bazaar

Vendor's Bazaar Commercial Vendors large & small hawking their wares

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 18th October 2011, 01:41 PM   #611
ChrisPa is offline ChrisPa  United Kingdom
diyAudio Member
 
Join Date: Jan 2005
Location: Saddleworth
Quote:
Originally Posted by phase_accurate View Post
I think the last answer was uncalled-for.
The poster asking the question about crossover distortion didn't make any posts in this thread before (so neither ranting ones). As far as I could see he was not even posting in class-d at all so one can assume that it was 1.) a honest question and 2.) he isn't aware of the special crossover distortion mechanisms that come into play with class-d amplifiers.
Agreed

Quote:
Originally Posted by phase_accurate View Post
Class-d in general do have a very different crossover behaviour than linear amps. There is always an alternating idling current flowing through the output inductor at no or low output power. This current is greatly supporting the switching process. At the very point when the output current in the load approaches the value of the idling current a class-d amp's crossover takes place. This is usually at a few watts. There are amps where this is intentionally pushed to higher output power levels by the use of smaller inductors (and therefore increased idling current). IIRC it was mentioned within the thread where this takes place for the ncore and if my memory serves me right it is between 20 and 30 Watts. Or in other words: At quite high output levels from a domestic point-of-view.

Regards

Charles
Which possibly/probably explains the 'bump' in the THD plots for the ncore at about 30W into 4ohms

http://www.hypex.nl/docs/nc1200%20folder%20web.pdf
  Reply With Quote
Old 18th October 2011, 02:51 PM   #612
diyAudio Member
 
Join Date: Mar 2011
Quote:
Originally Posted by ChrisPa View Post
Agreed

Which possibly/probably explains the 'bump' in the THD plots for the ncore at about 30W into 4ohms

http://www.hypex.nl/docs/nc1200%20folder%20web.pdf
And if so probably also the bump at 60-70W on the 8R plot.
(same current flow but double the voltage...)

The nice thing is the very low distortion plateau beneath these bumps which are very useful for most domestic listening
- on the assumption that low distortion relates to good sound of course

cheers,
  Reply With Quote
Old 18th October 2011, 03:43 PM   #613
diyAudio Member
 
Join Date: Jul 2010
Default I will

probably build up a nCore amp with the hopes that it will sound good enough for me to make the switch from A and A/B amps to class D for good. I sure would like to save the energy.
I have heard the uCD 400s here (with the Hypex deluxe linear supplies and HrX regs) and have a pir of ICE ASP 500 based monoblocks around as well. The uCD 400 was the best sounding class D amp I have heard, but still lost out to a traditional class A/B amp (Pass Labs X 150.5) for listening.
I look forward to the nCore DIY modules availability with high hopes.
  Reply With Quote
Old 22nd October 2011, 09:53 PM   #614
diyAudio Member
 
Join Date: Feb 2003
Location: San Francisco, CA
Will the nCore modules be available as a plate amplifier? I would really like to simplify my components and make my speakers active. A plate amp would certainly make the conversion easier.
  Reply With Quote
Old 26th October 2011, 08:06 PM   #615
diyAudio Member
 
Join Date: Mar 2010
when, when, when ?
  Reply With Quote
Old 30th October 2011, 08:53 PM   #616
diyAudio Member
 
Join Date: Jul 2004
Location: Mountain View, CA
Quote:
Originally Posted by phase_accurate View Post
Class-d in general do have a very different crossover behaviour than linear amps. There is always an alternating idling current flowing through the output inductor at no or low output power. This current is greatly supporting the switching process. At the very point when the output current in the load approaches the value of the idling current a class-d amp's crossover takes place.
Charles,

Very interesting; I had thought that crossover distortion wasn't an issue for class D because they don't construct the output waveform from two halves like AB design.

I guess this would be true for the IRS2092-based modules?

The only evidence I see in the curves starting on p.8 here

http://www.inductor.com/irf/iraudamp7s.pdf

is a small bump at 20W in some of the THD+N vs. power graphs, though curiously only in one channel.

What is the freq of this alternating idling current?

If the same as the PWM freq wouldn't it be inaudible?
__________________
-----------------------------------------
Noah

Last edited by noah katz; 30th October 2011 at 08:58 PM.
  Reply With Quote
Old 4th November 2011, 11:22 AM   #617
diyAudio Member
 
Join Date: Apr 2011
Default Ncore demo

Yesterday the Ncore amplifier demo was very convincing, both in theory and in an amazing experience in listening to music, not hearing any additions!
I hope to get 8 of these baby's for my new to build dig. controlled active system. Bruno, good luck!
  Reply With Quote
Old 4th November 2011, 12:25 PM   #618
jmbulg is offline jmbulg  Belgium
diyAudio Member
 
Join Date: Jan 2011
Quote:
Originally Posted by letimagesbefree View Post
Yesterday the Ncore amplifier demo was very convincing, both in theory and in an amazing experience in listening to music, not hearing any additions!
I hope to get 8 of these baby's for my new to build dig. controlled active system. Bruno, good luck!
What kind of installation did you use for the listening test? Any infos on the release date ?
  Reply With Quote
Old 4th November 2011, 01:30 PM   #619
cOz is offline cOz  United States
diyAudio Member
 
Join Date: Dec 2004
Location: Houston
Seems like these should be getting close to being released. I'm excited to see the release details like date and price!
  Reply With Quote
Old 4th November 2011, 03:32 PM   #620
diyAudio Member
 
Join Date: Apr 2011
Quote:
Originally Posted by jmbulg View Post
What kind of installation did you use for the listening test? Any infos on the release date ?
Ask Bruno for specific details, for it was organized by Hypex together with AES section NL.
Active loudspeakers: SEAS tweeter and mid; bass: Peerless
(think it was...)
  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
Hypex problem, who can help Hansms Class D 9 18th August 2013 06:49 AM
Hypex steveww Class D 14 18th November 2010 01:44 PM
Question for those who have tried hypex smps with hypex modules avian Class D 12 3rd March 2009 09:30 AM
Hypex UcD 180AD + signal wires, Power Supply ST, Hypex Transformer TR100A c10h12n2 Swap Meet 7 7th July 2007 03:55 PM
FS: Hypex UcD 400/180AD, hypex toroid Archmage Swap Meet 4 14th November 2006 04:23 AM


New To Site? Need Help?

All times are GMT. The time now is 05:07 PM.


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