Two LM 3886s on each side ?

DaveSail · 28th July 2010, 05:54 AM

I am using the case of a HAFLER SE120 Amplifier for my project . Today
I took the " guts " out . The heat - sinks on each side are large , and the
SE120 had two chips on each heat - sink . I wonder how much power each channel would have if I used two of the LM3886 units together for each channel . The two 300 VA units mentioned earlier would probably
still be enough power for two boards . And a bridge for each pair . ( Would the bridges have to be able to handle more power ? ) The threaded holes on the HAFLER heat - sinks are probably too close together for two boards side - by - side . I'd have to drill and tap a hole
in a location further away from the other one . I'm sure folks here know how to wire two together properly !

DAVID V. WEBBER

AndrewT · 28th July 2010, 11:15 AM

I have reached a conclusion by reading between the lines. I may be wrong.

I think you should assemble a 3886 based amplifier in mono and work out why it works and what it needs to work well, including Grounding. Then move on to the complications of two channel, parallel operation, bridged, packaging, etc.

DaveSail · 28th July 2010, 04:28 PM

Is this caution due to the fact that two boards are not just twice the work . Rather , the complexity goes up exponentially . More chances for
errors , and the results of those errors might be more serious . Then , the testing might be difficult and complex as well . ??

Still , I'm mostly just curious . What sort of power would each channel have , at a " normal " level ?

David V. Webber

lgreen · 28th July 2010, 10:20 PM

He is trying to dissuade you from failing at a complex project (search parallel chipamp) when you could succeed at a simple one.

benb · 28th July 2010, 11:09 PM

Here's a thread on a commercial product with THREE such amps in parallel. Some posters in the thread are complaining these things keep blowing out. Not sure if there's a relation there, but for what it's worth there's a schematic in post #29, and some possibly very important hints in post #30:
Event Studio Precision Repair
The thread's most recent post is yet another person asking for help with this product...

28th July 2010, 05:54 AM	#1
DaveSail diyAudio Member Join Date: Jul 2010	Two LM 3886s on each side ? I am using the case of a HAFLER SE120 Amplifier for my project . Today I took the " guts " out . The heat - sinks on each side are large , and the SE120 had two chips on each heat - sink . I wonder how much power each channel would have if I used two of the LM3886 units together for each channel . The two 300 VA units mentioned earlier would probably still be enough power for two boards . And a bridge for each pair . ( Would the bridges have to be able to handle more power ? ) The threaded holes on the HAFLER heat - sinks are probably too close together for two boards side - by - side . I'd have to drill and tap a hole in a location further away from the other one . I'm sure folks here know how to wire two together properly ! DAVID V. WEBBER

28th July 2010, 10:20 PM	#4
lgreen diyAudio Member Join Date: May 2003 Location: San Diego, USA	He is trying to dissuade you from failing at a complex project (search parallel chipamp) when you could succeed at a simple one. __________________ My DIY audio projects- PartTimeProjects.com.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
DIY build sound better than a good commercial design in a side-by-side comparison?	smellygas	Multi-Way	66	25th November 2009 08:26 PM
Difference between LM 833 and LM 4562	spiderze	Digital Source	3	22nd January 2008 07:27 PM
Powering bridged 3886s?	unitgain	Chip Amps	9	7th March 2004 07:51 PM
Side fire sub, how close can magnet be to side?	tim_rule	Multi-Way	2	2nd February 2003 08:22 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? 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

28th July 2010, 11:15 AM	#2
AndrewT diyAudio Member Join Date: Jul 2004 Location: Scottish Borders	I have reached a conclusion by reading between the lines. I may be wrong. I think you should assemble a 3886 based amplifier in mono and work out why it works and what it needs to work well, including Grounding. Then move on to the complications of two channel, parallel operation, bridged, packaging, etc. __________________ regards Andrew T.

28th July 2010, 04:28 PM	#3
DaveSail diyAudio Member Join Date: Jul 2010	Two 3886s Per Channel : Is this caution due to the fact that two boards are not just twice the work . Rather , the complexity goes up exponentially . More chances for errors , and the results of those errors might be more serious . Then , the testing might be difficult and complex as well . ?? Still , I'm mostly just curious . What sort of power would each channel have , at a " normal " level ? David V. Webber

28th July 2010, 11:09 PM	#5
benb diyAudio Member Join Date: Apr 2010	Here's a thread on a commercial product with THREE such amps in parallel. Some posters in the thread are complaining these things keep blowing out. Not sure if there's a relation there, but for what it's worth there's a schematic in post #29, and some possibly very important hints in post #30: Event Studio Precision Repair The thread's most recent post is yet another person asking for help with this product...

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)