how do I m0ar current 
On another note; two pieces of advice for all:
1) I was wrong to assume I should replace the 6 output caps with all .22uF. It sounded terrible. Major distortion even at low volume. Although I had also replaced the output inductors, but I doubt they were the culprit.
2) Always make sure you do a controlled discharge of the main power capacitor before you start removing and adding components. I bridged the cap contact point to something with my soldering iron yesterday, saw a nice spark while the volume LED glowed briefly and now -- dead amp.
Yes. I fry le Lepai. Glad it was only $20.
1) I was wrong to assume I should replace the 6 output caps with all .22uF. It sounded terrible. Major distortion even at low volume. Although I had also replaced the output inductors, but I doubt they were the culprit.
2) Always make sure you do a controlled discharge of the main power capacitor before you start removing and adding components. I bridged the cap contact point to something with my soldering iron yesterday, saw a nice spark while the volume LED glowed briefly and now -- dead amp.
Yes. I fry le Lepai. Glad it was only $20.
Hi Cogitech:
I currently do have the 12v, 5amp supply..
Do these tripath chips work anything like CPUs where more voltage makes them run "more stable"..
I'm not trying to overclock,
, but I'm just wondering if the circuit would be "lean" with lower than the recommended 13.5v from the spec-sheet Ah.. scary.. thanks for that tip.. Um.. I was under the impression that these small capacitors "don't " need to be discharged...before desoldering.
Do I just take my car-light bulbs and bridge the gap while it's still on the Board to discharge it?
As for the capacitors... I suppose I could put most of the old stuff back, and then swap in things one "set" at a time.. to make sure it's working right?
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Hi Cogitech:
I currently do have the 12v, 5amp supply..
Do these tripath chips work anything like CPUs where more voltage makes them run "more stable"..
I'm not trying to overclock,
I have seen people report good results with 13.5v supplies.
Um.. I was under the impression that these small capacitors "don't " need to be discharged...before desoldering.
Do I just take my car-light bulbs and bridge the gap while it's still on the Board to discharge it?
As for the capacitors... I suppose I could put most of the old stuff back, and then swap in things one "set" at a time.. to make sure it's working right?
Discharge them as you see fit. I use a resistor, when I remember to do it.
I do believe it makes sense to replace 1 thing (or a pair) at a time to see what happens. I am usually too impatient to do so, and I end up not knowing WTF is going on.
What does the increased voltage do.. does the 12v I'm using impair function in any way?
What exact inductors did you use? Using 0.22uF caps is very unlikely to cause that much distortion.
I always unplug, then turn the power switch on and leave it on. Same with pretty much all other equipment. You can tell by the led around the volume knob when it's discharged.
^ this works..
also, yea the .22uf caps, it's in the spec sheet..
I swapped 2x Panasonic .47uf film back into the "left" channel.. in the C_o capacitor positions
Leaving the right channel all .22uf wima mkp10
Auditioning them separately.. via the speaker balance slider on my pc
I feel like the .22uf right has more detail.
Now I'm wondering if .33uf would be better because my ghetto cheap speakers are only 6ohm
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What a mess I made of it. Oh well, it was a $20 lesson in what not to do. I'm OK with it.
I just bought this TA2020 Class T Audio Power Amplifier/AMP Board New Electronic boards | eBay which will be much more appropriate for my project.
I just bought this TA2020 Class T Audio Power Amplifier/AMP Board New Electronic boards | eBay which will be much more appropriate for my project.
You could Just buy a TA2020 IC and change the damaged one in the Lepai...
But that board seems nice one... Keep us informed how it sounds....
Is that board already put together for you? or you gotta glue?
Anyway.. I got a second lepai, because I wanted to compare with and without op-amps... before I rip them out completely..
I took the op amp out of the second board and went direct...
It sounded fine when playing from my sound card... But when I put in a shitty source like my iphone, the first lepai "with" the opamp -intact- is clearly superior...
Lepai #2 (opamps removed) sounded very uneven when playing from my phone...
I can't rule out that the improvement might be all the extra wimas and nichicons in lepai #1
BUT seemingly-likely,, you need the opamps if your source is something crappy like an i-phone..
But, idk, it could just be my iphone, i haerd iphone 5 audio isn't as good as samsung gs, so maybe people with samsung phones would be fine without the opamps.
^^ I bring this up because this is somewhat of a "mobile" amp...
ALthough, LOL mine doesn't fit in the case at all with all the caps.. I didn't want to significantly lengthen the path, so i just put the caps in place..
I'm probably still going to take my opamps out... but I thought I'd provide this comparison for those on the fence.
Anyway.. I got a second lepai, because I wanted to compare with and without op-amps... before I rip them out completely..
I took the op amp out of the second board and went direct...
It sounded fine when playing from my sound card... But when I put in a shitty source like my iphone, the first lepai "with" the opamp -intact- is clearly superior...
Lepai #2 (opamps removed) sounded very uneven when playing from my phone...
I can't rule out that the improvement might be all the extra wimas and nichicons in lepai #1
BUT seemingly-likely,, you need the opamps if your source is something crappy like an i-phone..
But, idk, it could just be my iphone, i haerd iphone 5 audio isn't as good as samsung gs, so maybe people with samsung phones would be fine without the opamps.
^^ I bring this up because this is somewhat of a "mobile" amp...
ALthough, LOL mine doesn't fit in the case at all with all the caps.. I didn't want to significantly lengthen the path, so i just put the caps in place..
I'm probably still going to take my opamps out... but I thought I'd provide this comparison for those on the fence.
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Which is the role of C20 and C21? Are they coupling caps?
Is there a complete schematic to understand a little better?
TX
well... the 2.2uf caps are in "what little" schematic we "do" have...
But yea, if you bypass and have a really good source.. I think just direct shoot would be "fine.." although you'd still at least need those 0.01uf in the loop for noise control going over "distance"
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