Simple amp with DC on the output...

[SkinnyBoy]

I tested it.....

less than 150mv with just the resistor on the input...

and

less than 50mv with the computer connected to it..

 

[li_gangyi]

great...so are you satisified with the final product??

 

[SkinnyBoy]

the heatsink is too small... it gets too hot... and I still haven;t added a cap to the input for DC filtering... I haven't blown the cones out of the 3inch woofers its running YET, but if I'm not carfull I probably will...

there is no way I could use this to run 4ohm speakers.. the heatsink is far too small... I might try and fan cool it or add some fins to it.. but space is really a problem...

 

[li_gangyi]

try water cooling...might also help the PC you are building this thing in...

 

[SkinnyBoy]

umm.. there is no space to water cool it..... it gets too hot to leave your hand on it.. lol

 

[li_gangyi]

hmmm...how about lifting the amp outta the PC?? or maybe free up a drive bay and use the whole space for a heatsink...

 

[SkinnyBoy]

the 3inch woofers cost $9 for the pair... they are sortof TLs.. they are sitting on my desk facing up with a 50cm piece of pipe resting ontop.... they have a usable response down to like 50Hz..... but not at too much power...

the amp cost me $2.70 to make (even cheaper than the speakers) all I had to buy was the speaker terminals...

EVERYTHING else was recycled, except the chips with are samples..

 

[SkinnyBoy]

hmmm...how about lifting the amp outta the PC?? or maybe free up a drive bay and use the whole space for a heatsink...

did you even read previous posts and look at the pictures?

 

[li_gangyi]

I did...maybe a thicker aluminium extrusion would help...how about a thick aluminium block...drileed and with fans at one side...to help dissapate heat...or attach some fins...

 

[SkinnyBoy]

I suppose I could at a PINCH bolt another piece of aluminium onto the back of the current heatsink, and bend it so it goes over the network card...

 

[li_gangyi]

wonder if it's enough for the amp...relocate the amp to the sides...and have heatsinks extruding out of the case?? Izzit a possibility?

 

[SkinnyBoy]

the amp has to stay where it is...

there is nowwhere else for it to go, and where it is the mains wires, and secondary connection to the transformer are as short as possible... as is the DC from the filter caps and bridge...

 

[carlosfm]

Hey Skinnyboy,

Even staying where they are, you have some space to put the chips on cpu heatsinks (with fan).
It may be tight, but I think it's manageable.
Fans working at low speed (lower voltage) don't make much noise and are effective.
lol.

 

[SkinnyBoy]

hmm.. I don't think I do have space.. lol the aluminium plate they are mounted on now rests on the motherboard, and the top of the case.... and, the surface that the chips are currently mounted on is only 4.5 cm high....

 

[li_gangyi]

that is really too small...will your mini PC have a cover?? Perhaps you can use a big heatsink as a cover..

 

[SkinnyBoy]

that is really too small...will your mini PC have a cover?? Perhaps you can use a big heatsink as a cover..

umm.. yes.. it will have a cover.....

no.. the cover can't be a heatsink...

 

[li_gangyi]

groans...how do we cool the amp then??

 

[SkinnyBoy]

we don't.. if it overheats.. it overheats... no big problem...

 

[carlosfm]

hmm.. I don't think I do have space.. lol the aluminium plate they are mounted on now rests on the motherboard, and the top of the case.... and, the surface that the chips are currently mounted on is only 4.5 cm high....

Naughty naughty, I see that you changed some things.
Your picture is from version 1.0, and now you're on version 1.1.
Is the new version better?
Well... at least it's .

 

[SkinnyBoy]

Naughty naughty, I see that you changed some things.
Your picture is from version 1.0, and now you're on version 1.1.
Is the new version better?
Well... at least it's .

umm.. no.. its the same... I'll remove the word "now" from the post you quoted.. (not literally)