silicon chip magazine 15w class a amp - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 24th April 2007, 10:52 PM   #1
diyAudio Member
 
Join Date: Feb 2006
Location: Essex
Default silicon chip magazine 15w class a amp

Hello

My name is Nick from the UK and i have been making power amps for the last 20 years, this is my 1st response to this forum. Most of my amps have been designed by JLH. I was thinking of making the SC magazine 15w class a as described in this post. Any chance some of you could send me the CCT diagram and pics of your amps if you have constructed the amp in question ? also what are your views on this amp as regards sound quality ? would be helpfull before I start construction

best regards

Nick
  Reply With Quote
Old 25th April 2007, 06:53 PM   #2
diyAudio Member
 
Join Date: Feb 2006
Location: Essex
Hello again

Any body ?? surley some one must of construted this power amp ? or is it no good ?

best regards

Nick
  Reply With Quote
Old 25th April 2007, 07:46 PM   #3
diyAudio Member
 
Join Date: Feb 2006
Location: Essex
ok

what would you all go for ?

JLH 15w class A or the SC magazine 15w class A design ?

regards

Nick
  Reply With Quote
Old 26th April 2007, 04:11 PM   #4
Netlist is offline Netlist  Belgium
diyAudio Moderator Emeritus
 
Netlist's Avatar
 
Join Date: Jan 2003
Nick,
I'm sure you will get more responce here in the Solid State forum.

/Hugo
  Reply With Quote
Old 26th April 2007, 04:18 PM   #5
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default Nick, please, post the schematic for us.


Will be easier, and better for us, to watch it in advance, this may result in some comments from us.

20 years constructing is telling me that you may have a lot of things to comment too.

If you came from other forum section, chip amps or another...a transference (moved for good), post the schematic once more.

regards,

Carlos
__________________
Instantaneous pcboard copper corrosion; https://www.youtube.com/watch?v=WED3Bvmxepk
  Reply With Quote
Old 26th April 2007, 06:46 PM   #6
diyAudio Member
 
Join Date: Feb 2006
Location: Essex
thanks for the feedback ... yes I am 42 these days a fully qualified electronics technician ,,, and I have had the audio bug since I was 14 years old. I have my own log cabin as a electronics workshop and dream of running my own company making audio gear ( all hand made ) at the highest quality possible ( well by me any way )
I will post some photos soon as I am still new new this site as I did not realise I was in the wrong section. I am a big fan of JLH as I have met the guy. I make highley modified JLH 80w mosfet power amps and a 250w bridged version .... you just need to see it also i have sold quite a few ... trying to get them CE approved

anyway

taking my wife out for a meal .... speak to you all when I get back

all the best

Nick
  Reply With Quote
Old 26th April 2007, 08:07 PM   #7
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default Well.... what to say...welcome brother.


This forum is an enormous brotherhood..filled with knowledge till the top....bad folks are not more than 10 when we have thousands of nice educated folks.

I hope you enjoy and give us contributions telling things about your experience, and contributing in our threads too.

regards,

Carlos
__________________
Instantaneous pcboard copper corrosion; https://www.youtube.com/watch?v=WED3Bvmxepk
  Reply With Quote
Old 26th April 2007, 08:53 PM   #8
diyAudio Member
 
Greg Erskine's Avatar
 
Join Date: Jan 2002
Location: Sydney/Australia
hi jamesfeline,

I was just reading the May 2007 Silicon Chip magazine and guess what?.... they have just published an update to the old 15W ULD class-A amp.

Here's a quote from the front page, "All-new 20W Class-A Amp, the lowest distortion of any amplifier ever published...anywhere in the world!!"

Note 2 explanation marks.

regards
__________________
Greg Erskine
  Reply With Quote
Old 27th April 2007, 12:28 AM   #9
sandyK is offline sandyK  Australia
diyAudio Member
 
Join Date: Apr 2007
Location: Sydney
Default Silicon Chip 15W Class A Amplifier

I have been using this amplifier since shortly after publication.
The editor of Silicon Chip (as an engineer) was quite embarrassed about subjective quality of this amplifier when compared to a previous Class AB magazine project. He seemed to put most of the major audible improvements down to the superior channel separation of the Class A .
As good as the basic amplifier is, it is very accomodating of modifications to both the amplifier PCBs and Power Supply.
The output transistors , for example , may be replaced by 2SA1302/2SC3281 (or the latest Toshiba devices) for even better results. Using 2 regulator boards further improves the performance, as does replacing their series pass transistors with MJE15030/15031.Further benefit may be obtained by using a Harbuch PTT4639 transformer (dual secondaries) and 2 bridge rectifiers.
There are MANY other refinements also, that I won't go into at this stage.
sandyK
  Reply With Quote
Old 27th April 2007, 04:35 AM   #10
diyAudio Member
 
Join Date: Mar 2001
Location: Sydney
I think you hit the nail on the head regarding Silicon Chip projects. Sure, the design may be good, but they could have gone just that bit further to make it really great. I find in virtually all their projects that component selection is lowest common denominator stuff, ie whatever cheap parts are available from Jaycar/Dick Smith will do. They rarely give consideration to capacitor types, even in the signal path, which I doubt even the biggest sceptics would argue over the benefits of film vs electro.

One example is Silicon Chip's Oct 2005 "the best preamplifier ever" project, which features 4 non polarised electros (2x47uF and 2x22uF) in the signal path of each channel!! Arrrgh! They also use the same relay to switch the left and right channel and the distance between tracks for the left and right channel is about 0.5mm (one channel's track actually runs through the relay terminals of the other channel). Don't get me started on the carbon volume pots running back to terminal blocks. I'm not attacking their design, just the fact they put these up as the "best ever" published (do they read Elektor?) and of "audiophile" quality. Oh, please.
  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
Aussies - Silicon Chip 20W Class A Amplifier opinions? wixy Solid State 39 4th November 2013 01:31 PM
Silicon Chip ULD amp Greg Erskine Solid State 20 18th March 2012 03:47 PM
HEI from June 98 Silicon Chip AKSA Solid State 3 1st March 2008 06:31 AM
Silicon Chips Magazine of AUSTRALIA leinahtan Everything Else 5 19th July 2005 02:00 PM


New To Site? Need Help?

All times are GMT. The time now is 10:09 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