Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Chip Amps Amplifiers based on integrated circuits

I want to build some Composite LM3886
I want to build some Composite LM3886
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
Thread Tools Search this Thread
Old 11th October 2019, 05:37 AM   #1
Clueless but avid is offline Clueless but avid  Germany
diyAudio Member
Join Date: Oct 2017
Default I want to build some Composite LM3886

Hey people,

I've built some tiny 2.5-way active floorstanding Speakers (2x 5" Mid/ Bass + 1" Softdome driven by three LM1875) which sound in my ears better than I ever expected.

I've built quite a few LM1875 Amps in different Variations, but it seems I'm not able to get original Chips in Germany. Most Resellers do not offer this Chip anymore, and Mouser, the only Shop where I found it seems to want 20 tax, which is a whole lot of money.
The idea is to build some composite LM3886, because this Chip is available everywhere. While I used Breadboard Boards for the LM1875 Amps, I want to make some PCB's for the LM3886es. Problem: many Threads, countless postings about this Stuff.

So my first Question: which PCB should I choose (the my_ref, or the audiophile approach or whatever), and where do I find a downloadable File with the best LM3886 PCB ever?

Best regards & many thx

  Reply With Quote
Old 11th October 2019, 07:30 AM   #2
chermann is offline chermann  Austria
diyAudio Member
Join Date: Jan 2017
Location: Vienna

yes you are right....its not easy to get a "original" LM1875 . for your speakers you need 6 pcs of LM1875 ...so 10 pcs is not bad -->
At the Texas instrument Shop (you have to register) you will get 10 pcs of LM1875 for 3,1 each - deliver+tax to my country is 6,99 Euro
sum= 38,09 euro

  Reply With Quote
Old 11th October 2019, 04:10 PM   #3
tomchr is offline tomchr  Canada
diyAudio Member
tomchr's Avatar
Join Date: Feb 2009
Location: Calgary
I'll throw my Modulus-86 into the mix.

If you'd rather build from scratch, Kitchin (et al.) "Composite Audio Power Amplifiers", Electronics Now Nov. 1992 is a good place to start. It'll take a bit of simulation work to adapt the circuit for the LM3886 and its quirks, but it's possible to do.

If you're interested in the quirks of the LM3886, I cover quite a few of them in my Taming the LM3886 article series: Taming the LM3886 Chip Amplifier

Modulus-86, 186, 286, 286 Kit, & 686: 40-240W (8Ω) at <-120dB THD.
Neurochrome : : Audio - www.neurochrome.com - Engineering : : Done : : Right
  Reply With Quote
Old 11th October 2019, 05:04 PM   #4
chermann is offline chermann  Austria
diyAudio Member
Join Date: Jan 2017
Location: Vienna
Good point by Tom!
if you want to start seriously with LM3886 then:
about 63 euro for a bare pcb Modulus 86 or about 36 euro for a bare pcb LM3886 done right

  Reply With Quote
Old 11th October 2019, 06:03 PM   #5
Clueless but avid is offline Clueless but avid  Germany
diyAudio Member
Join Date: Oct 2017
Hey Guys, I'm registered here for about 2 years. In this time I've read each Word on Neurochrome for at least a minimum of 5 times. Why? Because the Modulus- Series are excellent engineered Amplifiers and I always try to adapt the good things when I have to study autodidactic. The Problem is, my Profession is that of an industrial Mechanic. Industrial Mechanics are used to work with only two tools: A Hammer and a big Hammer. I'm pretty good at soldering, but as an old man of 50 years it's not always easy to learn audio electronics from the start in a foreign language. I guess most Users on this board are decades of experience ahead of me.

I'm a pretty different DIY Guy, too. A lot of things I cannot afford, I build myself. As a mechanic I'm good at Metalwork and as a 69er I still practice those ancient Knowledge-Rites like reading everything I find to a theme that interests me.
If I was the average DIYer I'd buy a couple of Modulus- Amps & everything is fine. For a fully activated 2.5-way Stereo/ Subwoofer System this would be 7 Amps. I cannot afford even one of them. But hey, so I have to dive deeper in and make those missing things by my own.

For I havn't managed to read those hundreds of sites with postings about the "my_ref", the "Modulus" and all the other LM3886 Composite approaches I just ask for your Recommendation with which PCB I'll have the least Problems & the best Sound.
Btw. at the moment I'm listening to Music with my Speakers driven by Fake LM1875, and those aren't sooo bad. I really like what I hear, but in my Imagination there are so many Speakers & Amps that need to be built, I have to go further than fake LM1875es.
(missing shrinking Tube on the Pic depends on missing shrinking Tube, but the wires cannot touch each other)

Best Regards
Attached Images
File Type: jpg last 1000h.jpg (345.6 KB, 109 views)

Last edited by Clueless but avid; 11th October 2019 at 06:05 PM.
  Reply With Quote


I want to build some Composite LM3886Hide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
LM3886 & LME49720 composite amp IO390 Chip Amps 131 Yesterday 11:43 AM
Composite amplifier: LM3886 + LME49710 jeanlemotan Chip Amps 111 9th October 2019 01:39 PM
My LM3886 Build Jennifer G Chip Amps 97 6th June 2016 06:57 AM
yet another lm3886 build doors666 Chip Amps 8 27th January 2015 06:54 AM
My LM3886 build thread CanAm Man Chip Amps 22 13th July 2012 07:48 AM

New To Site? Need Help?

All times are GMT. The time now is 10:03 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio