Help for a confused guy on chipamps

[tally3tally]

Ok so i was toying with an idea to build a power amp for my tritrix(8 ohms, under construction)
Requirements
a) Max possible ampification around 100Wpc.
b) should fit my budget which tops at around 10k
c) Should Fit my capability and limited ectronics knowledge.

For the purpose honed on to the MyRef posted by Linuxguru, shot him a mail regarding the availability of the kit he was procuring (he was prompt in responding, thanks).

Problem : The amps have a max power limitation of around 40watts.

Was researching on the application of the LM3886 in parallel and came across
http://www.diyaudio.com/forums/chip...inished-measured.html?perpage=25&pagenumber=1
http://www.shine7.com/audio/bpa300.htm
http://www.diyaudio.com/forums/group-buys/137430-bpa300-round-2-a.html


This project uses it in a bridged configuration to achieve 300W @4ohms mono.
Possible solution to my problem: I guessed i could use the same as 150W@8ohms stereo without bridging.

To top it all there is a parallel LM3886 combination available @ Ebay
LM3886 3 x 159W Parallel Mono Channel Amplifier Board - eBay (item 270644493655 end time Nov-02-10 21:31:50 PDT)

On closer inspection the Ebay board is a clone of the BPA300 which i was looking at as a possible solution.

Help required
a) Views and recommendations on the ebay thing.
b) I guess i should just require a trafo, heatsinks n chassis more to complete the project.
c) Help of the senior members to evaluate this n give an advice on the workability.

anurag

 

[linuxguru]

At some risk of stating the obvious, Mauro's MyRef is renowned for its stability, finesse and audible sonics with a wide variety of speaker loads. For most indoor listening at comfortable Sound Pressure Levels with typical 8-ohm speakers with efficiency in the range of 85..90 dB/Watt, 40W is far more than you'll need. The MyRef is not designed for ghetto-blasting 4 ohm automotive sub-woofers driven to Xmax.

That said, if you need higher power, you can source Mauro's Evolution board directly from him. It is the successor of the MyRef RevC, with a pair of LM3886s per channel. It is reputed to be just as refined as the MyRef, but can deliver about 80W+ into a 4 ohm load. The last time I checked, the board was available semi-assembled for about 200 Euro, but prices may have changed.

The Chinese 150W and 300W paralleled LM3886 boards are good value, but will not be anywhere close to the audible sonics, imaging, soundstage and detail of the MyRef or Evolution.

 

[somakmaitra]

you can give this sure amplifier a try
2*100 watt @ 4ohm TK2050 Class-D Audio Amplifier Board - eBay (item 230524834933 end time Oct-11-10 01:14:28 PDT)
They are based on tripath chips.
An smps will cost you around Rs 2500/-.
I have recently bought an TPA3123-Class-D (2x25W)Amplifier Board from them and I am pleasantly surprised by their sonic quality .Parts express is also selling the board I got them after reading a couple of positive reviews of the amps.

Picasa Web Albums - somak maitra - Sure electron...
they are small , green and requires very little power .I think you cannot make out any difference from the sound of a chip amp with that of a class d amp though I consider myself a novice in the context to the sonic qualities of different class of amps.

regards ,
Somak

 

[captrajesh]

@linuxguru, would it be possible to bridge the Myref monoblocks? What would be the outcome?

 

[spirovious]

Can a multich amp (5.1 with 3 tripath amps)be assembled with single power supply?
(for mov)
Or need to make 3 seperate amps?

 

[quad]

@linuxguru, would it be possible to bridge the Myref monoblocks? What would be the outcome?

AFAIK, it is not possible to bridge the MyRef monoblocks.
There is some good info on LM3886 parallel/bridge operation. Note
the parts about matching some critical resistors as closely as possible -

-=[ FirstClass :: Home Page ]=-

Another must-read is the BPA-200 tech note from National

Can a multich amp (5.1 with 3 tripath amps)be assembled with single power supply?

There are some 5.1 Tripath amp boards available from Arjen Halder and
also from ebay -

5.1 channals 3pcs TA2020 Amplifier board - eBay (item 200528772136 end time Oct-18-10 01:28:48 PDT)

 

[somakmaitra]

you can cascade classd please refer to the manual of sure electronics at partsexpress.com http://www.parts-express.com/pdf/320-304m.pdf

enclosing the diagram
somak

 

[GeorgeO]

Personally I dont think it is critical that you need to go for 100wpc, even 40 wpc will do most of what 100 will do. Again, this is my personal opinion. The key is to get started.

 

[tally3tally]

@Linuxguru
I have absoloutely no doubt regarding the beauty of your design of the Mauro Pensa GC.
If the tone of my post sounded(to you) in anyways that i am comparing your design with anyone-else's i am truly apologetic.

that said,
I was only stating my bright discovery and wanted some inputs regarding the same

the quality of the kit came into my mind at the first instance this made me wonder that maybe the biggest cost cutting measure employed must have been the parts..

the design of the project is not new as the Boards are clones of the BPA300.

will do some research and willl follow up on this thing