B&O ICEpower modules – any built? - Page 8 - 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 22nd September 2008, 02:12 PM   #71
diyAudio Member
 
theAnonymous1's Avatar
 
Join Date: Feb 2004
Location: Anonymityville
I did the swap for a few different reasons, but that is not to say I even need a reason. I can do whatever I want with my toys, even if that means breaking them.

Reasons for the swap.....

1) First and foremost; because I could.

2) To be the Guinea pig for others who might want to do the same for whatever reason (or no reason), but are hesitant because it might have negative effects and they aren't risk takers.

3) Technically speaking the 33078/9 is inferior to the LME. That's no guarantee that the LME will sound better in this specific application, but it's enough to reinforce my first two reasons.

Reference: http://www.sg-acoustics.ch/analogue_...distortion.pdf

4) Placebo is stronger than my actual perception of any change. I believe the LME to be better, so it is. It doesn't matter what anyone else thinks.
  Reply With Quote
Old 23rd September 2008, 12:15 PM   #72
diyAudio Member
 
Join Date: Sep 2004
Location: n/a
Quote:
An extremely odd comment. How could anyone know if there would be improvements until AFTER the components were changed?
I will give it a try to reply to the post #70 of Bwaslo.

> An extremely odd comment. How could anyone know if there would be improvements until AFTER the components were changed?

My point is there should be a reason to change components. I did not hear any ‘complains’ about the sound of your ASC200 board. I am happy with the way the ASC200 board sounds. Bass is exceptional, a lot of slam and very dry. Soundstage is very nice, but good be a little better, highs are a fine but some more refined/detailed presentation is also possible. On a speaker like the Tannoy Yorkminster SE this last remark seems/feels so, this compared to a Tom Evans 4xEL84PSE amplifier. On a Tannoy TD700 this ASC200 board sounds so impressive that you just listen to the music, you will play one disc after the other. My own Dynaudios (17W75XL + Esotar in 10 ltr cabinet) do like this amp, they tend to be ‘brilliant’ but than in a good way, but with this ASC200 board everything sounds very in balance, I can live with this. Also what is missing is some drive (timing?). For example Arcadi Volodis Live in Carnegie Hall (classical piano solo) makes this clear, this disc is very well recorded and even better performed, it feels your are there (the silences, the drama and expression of his playing), my 6336PP tube amp and ECL82 based hybrid amplifier achieve better results in this. So if I would ‘modify’ the ASC200 aboard I would search for some more high details and some better timing.

People can hear differences in amplifier, speakers, cables and so on, no doubt about this. So next step is in circuitry and components.

So next thing would be to search for components which will do so. This ASC200 board is not just an amplifier, it is a box (read: board) full of tricks, compromises and design techniques, leading in a heck of an amplifier. If we are going to do some modifications a difficult thing is ahead, this because we don’t have a detailed schematic/circuitry. And also because the use of SMD. I feel this board is not the thing to experiment with.
The PSU and the output section including the ICEPower control circuitry should be left alone. So coupling caps (if any) and opamps can be changed. The MC33078/79 does scream for replacement. In a former project (stand-alone DAC using a Crystal/Cirrus evaluation board) a MC33078 was used, this one could be easily changed because it was using a normal DIP8 IC socket. Almost any double opamp gave an better overall sound, this for sure in terms of drive and dynamic behaviour.
About the ‘right’ choice of opamp for the use with the ASC200 board. The LM4562 could be a ‘good’ choice, this because to my opinion it adds something in the highs, to me something not natural, but lot of people like this opamp. This LM4562 could ‘compensate’ somehow and can make things in balance. The LM4562 seems not my favourite in drive or timing, the OPA2134 family does, so I would go first for the OPA2134 family. At the moment I am happy with my board as it is, so will not do any modifying.

> I beg to differ. Memory of sound is notoriously unreliable.

About how components ‘sound’ and how I have learned. A Rotel preamp or a standalone DAC is very suitable for easy change of components and use in the process of learning about components. Schematics are available and normal size components, so changing something is done in no time. For example opamps. Choose 2 opamps you want to evaluate and make a listing on paper with some points like soundstage, air, bass, highs and so. Some detailed info in the music; for example in Keith Jarrett’s Koln Concert in the opening you can hear and feel a door open and close, at some systems you are not aware of this. Things of you think is important. Choose for a recording you know and heard on several different systems, my experience is that piano solo is a good choice. But than I like piano. I use very often a live recording by Michel Petrucciani, first a spoken announcement by male person, than applause, than his playing, together max. 1 minute. I heard this on some many systems and can relate this.
Next. First write which opamp is which and play your music excerpt demo of max. of 1 minute. Change to the other opamp, do this 2 or 3 times and later maybe with some other music. Than do the blind test, do all things all over now not knowing which opamp is which. Put some tape on the opamp and try to relate the things you wrote down on paper to the opamp you are listened to. This process needs time, I spend many hours like this. I ‘fooled’ myself and others by thinking this is the ‘one’, and after removing the tape it turned out to be a cheapo OP176 (single version of the OP275).
You could do the same for coupling caps or PSU parts like decoupling caps. This is how I learned and could choose my DAC out of 3 other ones (and this 3 times) with no problem, because I could recognize certain sound behaviour or maybe better I could relate the sound what I knew about my DAC behaviour. I modified once a Philips DAC960 stand-alone digital-to-analog convertor, having a second one (the original) to compare. In this way you learn what components can do yes or no. I spend many hours/days with this DAC960 output filtering using different filter configurations, coupling caps, decoupling caps, the PSU and so on.
I build a hybrid amplifier using different power transistors, 2 the same amplifier boards one using the 2SC3263 power transistors, the other 2SC5200, and yes there is a difference, the 2SC5200 one gives a better overall presentation, more joyable sound. Don’t ask me why or how, I am a medical engineer, so have no believe in this, but my ears telling me something else.

> But so far I'm not aware of anyone who actually has (only of lots and lots who claim they could or that such differences are "so obvious" that a test isn't necessary;

A very close friend is a professional piano player and you can play a certain tone and she knows what tone it is, she is so trained (and talented) that she can do they same with chords. I play them, she reproduces them. I don’t have this at all. But I can hear the differences in recording dates of a professional made recording by a former Philips engineer, he was amazed that I could figure out.

I once won a Van de Hul interlink cable, because you had to guess how many time they switched between to cable, I can’t remember the time period, but they changed 12 times, no clicks or what-so-ever good be noticed.

> or that they "could" but they can't be bothered to got to the trouble to demonstrate to anyone else at, say an AES convention or other audio show where audiophiles already gather).

AES and audio show are different. The AES is for professionals and I attended the ones here in Amsterdam. Some of these people are also not always honest to them self, I do know this person who sells B&K microphones and they have this capsules for SACD recordings, in some SACD recording demo they used some B&K clones with no extend over 24kHz. So question was how can they demo SACD if their microphones are not capable of recording the high frequencies as claimed. The person who gave the demo was not aware of the B&K clone specs.
I attended the first demo at an AES convention of Sony’s Atrac system, I did not get into the discussion with the pros, but I ‘voted’ that the Atrac system sounded worse, and in the end it turned out that 75% of the panel had also this opinion. This was a blind test and a several changes, you had to guess which number was playing, so with Atrac or without. Burr Brown engineers mentioned at a seminar that it would be ‘impossible’ to hear differences between the PCM63 and back than the new PCM1702, many professional designers disagreed with this. Same with some Crystal engineers, they could not be convinced that the use of components on their evaluation boards ruined the sound, wrong choice of filtering caps and opamps. BTW, they were also very found of the MC33078.

> Sorry to be testy, but really, statements like yours are a dime a thousand, easy to come by. Actual evidence on the subject, though, appears to be sorely lacking.

Hope you got more believe in me.
  Reply With Quote
Old 3rd October 2008, 08:11 AM   #73
ppchiu is offline ppchiu  Canada
diyAudio Member
 
Join Date: Aug 2008
Has anyone compared these modules to some retail icepower amps?
  Reply With Quote
Old 3rd October 2008, 01:01 PM   #74
john65b is offline john65b  United States
diyAudio Member
 
john65b's Avatar
 
Join Date: Jan 2005
Location: Chicago
I had a Bel Canto S300 with th exact modules. I only had it in my system for a month or so before I sold it - total impulse buy, but I knew I would be able to get my money back as they were very popular. Sold it within three days.

Compared to my UCD400AD, it sounded bland. Of course the UCD was well-broken in and over twice the power...

I bough four of the ASC modules because they were inexpensive, and I wanted to experiment with the DCX 2496 digital crossover bi-amping my magnepans.

Project on hold at the moment....
__________________
All right, but apart from the sanitation, medicine, education, wine, public order, irrigation, roads, the fresh water system and public health, what have the Romans ever done for us? Life of Brian
  Reply With Quote
Old 3rd October 2008, 07:56 PM   #75
ppchiu is offline ppchiu  Canada
diyAudio Member
 
Join Date: Aug 2008
I wish i was aware of their presence when they were at $139. I ended up bidding for them for 300. I figure the reviews on the Bel Canto S300 & and Rotel 1072 were very good on avg so $300 very cheap in that sense.

I also seeked alternatives but once you factor in the power supply, extra protection modules and what not that the UCD180s require, it would be well over $300.
  Reply With Quote
Old 3rd October 2008, 08:50 PM   #76
john65b is offline john65b  United States
diyAudio Member
 
john65b's Avatar
 
Join Date: Jan 2005
Location: Chicago
I was one of lucky SOB's that picked up four for $69 each. I wish I could get back to building them - a little busy at the moment...

On the cheap for a class D? I would try the Motorola DCP-501. Has 5 channels of Tripath TA3020 that is more powerfull than these Icepower modules - all for less than $100 with power supply, dvd player, tuner, etc. You will need to read up on the modding that Anonymous1 and others did...these were the best class D bargains, seconded by these icepower deals...

Still have mine, somewhere...they did not sound bad after some simple mods.
__________________
All right, but apart from the sanitation, medicine, education, wine, public order, irrigation, roads, the fresh water system and public health, what have the Romans ever done for us? Life of Brian
  Reply With Quote
Old 4th January 2009, 04:56 AM   #77
lazenna is offline lazenna  Australia
diyAudio Member
 
Join Date: May 2007
Hi guys.I have the B&o 1000asp and want to build a mono block can anyone tell me if this switch is ok for Australia's 240 volt power.And what about the led does it need anything resistor etc' to protect it from the 240 volt mains.Thx.
http://www.gammods.com.au/store/inde...roducts_id=346
  Reply With Quote
Old 4th January 2009, 09:44 AM   #78
Nisbeth is offline Nisbeth  Denmark
diyAudio Member
 
Nisbeth's Avatar
 
Join Date: Jan 2001
Location: Denmark
That's useless for a 1000ASP. You'll have to find something rated around 10A and able to take a high inrush current.


/U.
  Reply With Quote
Old 4th January 2009, 10:34 AM   #79
lazenna is offline lazenna  Australia
diyAudio Member
 
Join Date: May 2007
Thx Nisbeth,do you or anyone else have any suggestions where I can try. I want it flush but with a blue dot led in the middle if possible.
  Reply With Quote
Old 4th January 2009, 10:45 AM   #80
Nisbeth is offline Nisbeth  Denmark
diyAudio Member
 
Nisbeth's Avatar
 
Join Date: Jan 2001
Location: Denmark
Don't think you'll find anything like that. The switches that I know of that will fit my description are mostly very "unsexy" rocker switches. If they are illuminated it's usually in red or green.


/U.
  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
Icepower Modules spchu Class D 15 23rd May 2011 11:24 PM
New 3rd Generation ICEpower modules.... TheShaman Class D 8 16th February 2009 04:44 PM
Icepower car amps for modules? bwaslo Class D 3 10th September 2008 06:42 PM


New To Site? Need Help?

All times are GMT. The time now is 08:17 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