lm3886 and differant volumes

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Finally got my lm3886 up and running after a very bumpy start, only thin now is im getting two differant volumes on each channel, i dont have a pot wired up just a power amp, ive had it wired to a couple of sources and no change. my right channal is conciderable louder than my left, ive gone through and checked all my wiring/solder joints and im using the same speaker on each channel aswell.

any ideas?
 
Mine was following the building of a point to point amp. I seem to remember that I had something tied to ground which was restricting the input signal. Have you checked that you have no solder joins.

How did you blow the caps ? Did you blow the caps on both boards or just one. If just one, is this the board that has the problem. Have you blown any tracks ?
 
ok got it all up and running, i have no idea what it was it ust all of a sudden come to life.
I do however have another problem now, connected to a source that has seperate grounds for each input the amp works fine however hooked to my pc through the headphone jack i can only get a single channel at a time, its as if the amp doesnt like the shared ground of the head phone jack!
Its its the same when i have the volume pot solderd in.
 
Bit of an update for you fellas, got the problem sorted, it was the interconnect :( all that fussing and hassle with the amp and it wasnt even that. of course the interconnects were home made, it was a dry joint on the earth of the rca plug.

A question now though, a shared ground on the left and right channel of the input.. a good thing or bad thing?
 
HAHA! thats pretty smart, how big are the toroids that thing must be a hefty weight with 2 in.
Is there much advantage to the dual mono setup over the stereo?
I opted for a large 2x25v @ 4.5a a rail though it mesures 28v @ the secondries, im thinking its a little overkill though as cooling is a bit tricky at sustained high volume, i have a P4 heatsink on each chip for now and they get a bit hot to handle after 15-20 minutes of high high volume.

Im thinking about making a stepped Attenuator for it once i have my speaker driver replaced, as for a case at the moment its just in a cambridge audio A1 mk3 case untill i sort something a bit more perminant for it.

The power supply semes to be pretty highly rated for what it is, does this have a place in other projects or is it eally just for the chipamp.com kits?
 
Nuuk. You know I have never really listened to it for any length of time ! After I made it I got bitten by the bug to make a P2P version, then a bridged version, then 3875.......yawn..............etc etc. The trannys are only 80va each.

I look at it now as my "design project" as all other stuff built since sit on crappy bits of wood that I can find in the garage. I like to post pictures of it to show off !

Incidentally I don't know if you may have any ideas, I made some parallelled 3875's they work fine, but for some reason if I remove the input lead, I get a nasty screeching noise, which suggests that something is not right. I think I got the schematic from the ESP site. I will dig it out and post it.
 
Im prolly not the best person to ask as my knowladge is limited to what i researched and learnt on this project, one thing i do know is with my when connecting my input as i insert the rca plug and positive center pin is the only thing making connection, as in no earth on the input i get a nasty horrible buzz/hum, now i dont know what your sound is like compared to mine but does it ring any bells form past projects as in a referance to the sound?
I only state as could it be a short on the live?
 
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