eBay mono LM1875 kit

Received my kits but are damaged so on hold until I get replacements.

Must have been run over. :eek:

Needed the PCBs but the components were going to be thrown out.
 

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lLM1875T chips

When I received the kits I had a look at the chips and compared to the others I had.

A. An Australian supplier who does substitute when original is not in stock. This one has 2 indents on the face, one above pin 1 and the other higher above pin 5. Looks like they have a manufacturing code in them B8/14 and B9/1. Not genuine from TI for sure.

B. As supplied with the kit and the cutouts in the sides looks like that of a TDA2050 from the pic at ESP P72 so unlikely to be a LM1875T.

C. LM1875T/NOPB supplied by Digikey which would be from TI.
 

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Well, I have been more pragmatic. I bought 4 pcb's of which I´m using two as a test bench while saving the other two for the final configuration.

I don't mind using these cheap components to try different things and at the same time I like to see what effect the cheap components have for changing more expensive ones.

I have never had a very clear idea of how to use this amplifier as a headphone amp so I am simply dedicating to do test.
 
V nice clean build.
Don't fully understand Why you are fiddling about with these then? Definitely smaller than a full amp, less shelf space required.
Would be V surprised if an lm1875 cobble up, matched performances to your photo'd build.
My Lm3886 adventures were simply outclassed by My Firstwatt builds.
Better bass, mids and highs , a room deep soundstage was the real eyeopener tho.
Nelson pens a Fine circuit indeed.

If boredom is the impetus .. Perhaps a Lady friend ?
Although those can be exotic and certainly Expensive adventures ;)
 
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DIY is more cheaper and less complicated. :D:D:D

Returning to LM1845, I am not looking for something better than Papa and Wayne's projects, simply I like play and learn.

I tested a channel with an original LM1875 and indeed, the chip supplied in the kit is a TDA.

The LM1875 is brighter, less warm. I would not rate it as better only different but I need some more time to form an opinion.
 
Hmm... the 1875 'chips' included in MY 2$ amp kits are Definitely Fakes.. Not even passable copies..
Simple visual comparison alone..between these and Genuine (from Mouser) 1875's Left me with zero doubts.
No subtleties involved there.

I recently received a 'Genuine' 5532 chip to replace the 5532 I bought to erm .. replace.. the suspect one included in a 10$ 7377 2.1 amp kit.
I bought the first replacement at the local Chinese run Ebay junk electronics reseller shop. His 5532 looked credible and of course he swore that it was a Genuine part :rolleyes:
Swapped in the Real one.... the audible difference was immediate.

Caveat Emptor :D
 
planning.....the housing

Hi


i just play around with the possibilities of a housing (i used this for my TPA3255 "fake amp") and the internal boards.
https://www.amazon.de/dp/B017VIIDN4...ascsubtag=94c08f68c2a4b11d022dd960c5c1d695_CT


pic1 160VA with its dimensions (i bought a 300V for a other project) + big rectifier board + both channels - here is the room for the amp boards limited and t1 board is near to the transformer - not good

pic2 the same but with small psu board (rectifier and caps - no crc..) - here its better for short input signal ways.
oh...yes the transformer should be placed in the middle ;)
pic 3 is just the size of the heat sink = 6cm and the height of the board with possible stands and the lm1875.
pic 4 is the front panel -i like this kind of housing:)


chris
 

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