Chainclones - how do they sound - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

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 29th November 2003, 02:27 AM   #1
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Default Chainclones - how do they sound

I currently run a 10-inch subwoofer with one LM3886. Not too powerful, so I want to build something bigger. I looked at the Class D LM4651/2 from national, but it seems a little too complicates. Unless somebody has some pcbs using through hole components, I would like to stay away from something that complicated. I then found the Chainclone - http://www.euronet.nl/~mgw/diy/amps/...inclone_1.html - and was wondering if anybody has used one of these before. If so, did anybody use it for a subwoofer? How does it sound? Is it better than the 4651/2?

Another idea I had was to build a stereo amp to drive my B&W DM580 speakers. If I am right, a bridged 3886 can do 220W into 8-ohm, so 440 into 4 and 880 into 2? My speakers are 8-ohm but 220W per channel is still pretty impressive. Or, since my speakers are 8-ohm, would I be better off just using 4 chips instead of 8 and not paralleling them? Can the 3886 drive a 4-ohm load in bridged mode at all?

Any ideas on the sub amp? Would it be worth it to just make a pcb and use the 4651/2?
  Reply With Quote
Old 29th November 2003, 04:05 AM   #2
usekgb is offline usekgb  United States
diyAudio Member
 
usekgb's Avatar
 
Join Date: Feb 2003
Location: Salt Lake City, UT, USA
I'm not familiar with the chainclone, so I can't comment there. As far as using 4 chips, you are going to have to parallel two pairs of them. You then bridge the two paralleled pairs. This will get you the bridged power you are looking for, and will also deliver plent of current to give you the low eon oomph we all love so much.

Cheers,
Zach
  Reply With Quote
Old 29th November 2003, 04:10 AM   #3
usekgb is offline usekgb  United States
diyAudio Member
 
usekgb's Avatar
 
Join Date: Feb 2003
Location: Salt Lake City, UT, USA
OK, I just looked at the Chainclone thing. This is a very similar layout to the one that National Semiconductor published. It's basically a bridged/paralled design. It should work great for your sub. It will give you about 220 watts at 8ohms in to your sub.

Cheers,
Zach
  Reply With Quote
Old 29th November 2003, 11:15 AM   #4
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
And almost 440W into my 4-ohm sub speaker?

If so, that has some good things. and some bad things. Good, thats a ton of power. Bad news, my subwooofer is a 100WRMS with a 300W handling. Is that too much?

Do I need a larger transformer to get 440W into 4-ohm than to get 220W into 8-ohm? Or would the one on that page work?

How do you bridge them together? Just connect the inputs together and use one output for one side of the speaker and the other for the other side?

If anybody has done this, does anybody have the pcb layout for one channel?

Thanks, Mike
  Reply With Quote
Old 29th November 2003, 11:24 AM   #5
diyAudio Member
 
bigparsnip's Avatar
 
Join Date: Apr 2003
Location: Cambridge
Hi, you won't be able to double the power into a smaller load with this design, as the chips become limited by their maximum output current, and thermal dissipation, but you would probably still get around 300WPC, perhaps a little more, which is still quite a lot.

As far as these paticular circuits go, I'm not too sure how they would perform, as the are not totaly even in allrespects. Mainly, you have the inverting amp with Zin of around 1K Ohm, and the non-inveting with an input impedace about equal to that of the chip itself, which will be a lot higher.

Now, I have never built anything like this before, but I am guessig that as the input will drive the two halfs differently, you will have slightly different outputs on each half which could add a large amount of distortion, depending on how ideal your driver is.
  Reply With Quote
Old 29th November 2003, 11:44 AM   #6
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
Would I be better off using the schematic from national's datasheet? If so, what is that opamp on the input for?

I would like the second one better since there is less parts, but on that one I really have no idea what that odd opamp is on the input.

heres the schematics:

Another Bridge/Parallel Gainclone Question...
  Reply With Quote
Old 29th November 2003, 11:52 AM   #7
diyAudio Member
 
bigparsnip's Avatar
 
Join Date: Apr 2003
Location: Cambridge
Hi, Jojo whent for the second schematic in the end, as it was easier to match everything up than the first one and he seemed to be haappy with it when he was finished.

As far as the op-amp thing at the front of the circuit, that is just a buffer, that will give you a non-inverted and an inverted output (ballanced), so that you can feed the out of phase signals to each half of the bridge when they are both either inverting or non-inverting designs.
  Reply With Quote
Old 29th November 2003, 11:57 AM   #8
Optical is offline Optical  New Zealand
diyAudio Member
 
Join Date: Nov 2002
Location: Auckland, New Zealand
The opamp at the beginning is just a buffer, and does just that, perhaps not crucial... but id say that would depend on whats driving it

Im personally about to embark on the circuit with the DRV134 at the input as (like bigparsnip says) id rather have each opamp running in the same mode to make it easier to match everything
  Reply With Quote
Old 29th November 2003, 11:58 AM   #9
Optical is offline Optical  New Zealand
diyAudio Member
 
Join Date: Nov 2002
Location: Auckland, New Zealand
snap
  Reply With Quote
Old 29th November 2003, 12:24 PM   #10
diyAudio Member
 
Join Date: Sep 2003
Location: Illinois
First, what do you mean by snap?

second, can I just use a standard audio opamp at the input such as a 386? I am using a crossover based on the lm837 if that would do the same buffereing thing.

And yes, I think i will go with the second one also, it is less parts and less to explode when I short somethig out.
  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
PC sound card sound chips kaluchka Chip Amps 6 20th June 2011 03:48 PM
SE sound vs Ultra Linear sound flysig Tubes / Valves 1 9th May 2009 10:21 PM
Eighteen Sound (18 Sound) NSD 1095N Compression Drivers and XT1086 Horns opc Swap Meet 6 1st May 2009 03:48 AM
Sound, Sound, and more Sound - Instractables Nordic Everything Else 0 5th March 2008 05:43 PM
Roland VS-1 Sound Module - No Sound! jazzbee Instruments and Amps 1 3rd March 2006 08:39 PM


New To Site? Need Help?

All times are GMT. The time now is 10:55 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