Burning Amp BA-3b (Balanced) - diyAudio
Go Back   Home > Forums > Blogs > My DIY projects
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
I returned to DIY electronics in 2009 after a 20 year pause by building a few kits to get in shape. This blog is for me to keep track of my progress.
Rate this Entry

Burning Amp BA-3b (Balanced)

Posted 9th April 2013 at 06:10 PM by alexcp
Updated 11th April 2016 at 08:24 PM by alexcp (Added better photos)

Big, hot, and heavy! Just completed it and adjusted for distortion, have not had yet a real chance to listen to it. (Update: I have listened to this amp for some time, and it seems to be a keeper, at least for now.) The discussion is here.

The build is in a 4U/400 case from modushop; each side has two 200mm heatsinks, each holding six MOSFETs (three complementary pairs) and a biasing circuit.

The construction is dual mono (separate transformers for each channel) with CRC filtered +/- 18V rails, quiescent current is 3A per channel. Eight Mundorf MLytic® HC High Current Power Caps and two 300VA toroids occupy the most of the chassis, while the actual electronics is mounted on the sides.

Now I need a balanced preamp. I contemplate building some variant of BoSoZ, but am also thinking about a SuperSymmetric balanced preamp using JFETs or tubes...

UPDATE: No- and low-feedback amplifiers have no (or little) control over output errors and thus poor PSRR. On this premise, I replaced the CRC filters in the power supply of my BA3B with CLCs, so instead of 22mF + (2 x 0.22ohm) + 22mF I now have 100mF + 10mH + 100mF per rail per channel. I still need to give it a listen after this upgrade.
Attached Thumbnails
Click image for larger version

Name:	diyaudio32.jpg
Views:	636
Size:	217.7 KB
ID:	1010   Click image for larger version

Name:	diyaudio33.jpg
Views:	817
Size:	158.8 KB
ID:	1011   Click image for larger version

Name:	diyaudio34.jpg
Views:	972
Size:	226.8 KB
ID:	1012   Click image for larger version

Name:	diyaudio35.jpg
Views:	2413
Size:	231.0 KB
ID:	1013   Click image for larger version

Name:	diyaudio36.jpg
Views:	841
Size:	242.5 KB
ID:	1014  

Click image for larger version

Name:	diyaudio37.jpg
Views:	1639
Size:	242.1 KB
ID:	1015   Click image for larger version

Name:	diyaudio39.jpg
Views:	593
Size:	156.3 KB
ID:	1016   Click image for larger version

Name:	diyaudio41.jpg
Views:	684
Size:	192.2 KB
ID:	1017   Click image for larger version

Name:	diyaudio43.jpg
Views:	740
Size:	167.0 KB
ID:	1018   Click image for larger version

Name:	diyaudio45.jpg
Views:	2666
Size:	253.2 KB
ID:	1019  

Views 2556 Comments 0
Total Comments 0

Comments

 
Hide this!Advertise here!

New To Site? Need Help?

All times are GMT. The time now is 06:06 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright ©1999-2016 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki