Gainclone LM3876 build thred

[Forsman]

I just want to show what I’ve been putting together. This is my first ever amplifiers build. When I started I didn’t know the difference between a capacitor and an inductor. I’m far from sure that this implementation is a good one but as far as I can judge I think it sounds pretty ok

I had a 300 VA 30 V trafo to start with and I dident whant that high voltage why I chosed to use Carlos Phillipes regulated PSU.



It turned out like this.





When it comes to the amplifier part I looked at RJM Audio and have used his schematic but with some minor modifications to fit LM3876.



After serveral tries I was finally satisfied with this small cuties.





Each heat sink has thermal resistance of 1,85 C/W.

[Forsman]

Some more pictures.

















Well, I think it deserves some clothes to…

[coolbeer]

You forgot the most important thing! How does it sound?

[Forsman]

I left that part out on purpose. I am not an expert listener and don’t have so much to compare with. But I can compare it with a cheap compact system which I had home for a while and yes, there is big difference. Today I use it with a pair of Bjohannesens TABAQ. The sound is, compared to the compact system, very clean and detailed with good bas performance. I don’t really have anything to remark on. I am very satisfied over all.

There is no humming, no clicks and it is quiet between songs. There is only a very low ambient ssss-sound coming out of the speaker an on full volume you cant hear it 2 feet away from the driver.

However I don’t have any view if it is h hifi or not, but I hope it is

[coolbeer]

Honestly it does not matter in my mind if it's "hi-fi" or not, aslong as you are happy with the sound. I will be making my own gainclones eventually and it'll be fun to compare it to my NAD surround receiver.

You do however need to toss it into a box of somekind, looks a bit... naked :P

[ratza]

Originally Posted by Forsman

There is no humming, no clicks and it is quiet between songs. There is only a very low ambient ssss-sound coming out of the speaker an on full volume you cant hear it 2 feet away from the driver.

Disconnect the source and try it again, you might have a pleasant surprise
I'm almost sure that the noise comes out from the source.

[Forsman]

Originally Posted by ratza

Disconnect the source and try it again, you might have a pleasant surprise
I'm almost sure that the noise comes out from the source.

True, with the source disconnected the sss-sound is almost gone. To hear it at all I have to put my ear as close as an inch or two from the driver.

[Forsman]

Now I’ve started with the housing. I think I’ll try to build something cube like in oak. Haven’t made friend with my mill yet. It shoots away my pieces for the housing in the garage like frisbees, almost

[acold7dusta]

looks like you could use a longer bit

[Forsman]

- or a different tool, like a saw perhaps