I know it just a cheap little Lepai Lp2020a+ but, for my first amp mod, I didn't want to spend much only to have it release it's Magic Smoke due to my ignorance. I wiped about 75% of the factory SMDs off the PCB and replaced with Audyn input caps, Wima caps and Wurth inductors on the output side, omited the factory "bass" and treble" controls, removed the lettering on top of the case and took it down to bare aluminum as well as fabricating new end plates. Machined a new aluminum volume knob and reused one of the LED "ON" lights. Shoved it all back into the small case and it still works. 
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I know it just a cheap little Lepai Lp2020a+ but, for my first amp mod, I didn't want to spend much only to have it release it's Magic Smoke due to my ignorance. I wiped about 75% of the factory SMDs off the PCB and replaced with Audyn input caps, Wima caps and Wurth inductors on the output side, omited the factory "bass" and treble" controls, removed the lettering on top of the case and took it down to bare aluminum as well as fabricating new end plates. Machined a new aluminum volume knob and reused one of the LED "ON" lights. Shoved it all back into the small case and it still works.
But how 'much' better does it sound over the original parts? IOW, was the additional cost worth the payoff in terms of sonic improvements?
Better? Yes. Worth it? That would be subjective. For me, it was, from the stand point of learning something new. I viewed it as more of a learning process than looking for any big gains in performance. I think my next step will be to scratch build a LM3886 amp instead of modifying and existing one.
All together, I added about $30.00 in parts to a base price of about $20.00 for the amp. Add in the shipping and it totals around $65.00
All together, I added about $30.00 in parts to a base price of about $20.00 for the amp. Add in the shipping and it totals around $65.00
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They/links are not showing up properly. Try attaching them.Here are a couple more of the insides...
Great pictures Thump. I guess you did gut the amp and start over.
It was my firewall at work that didn't allow the pictures to be displayed. I see them fine now that I'm home. Not sure what the difference is, because images come thru fine. 
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Deleted member 148505
My Class D amplifier.
An Iraudamp1 derivative. Onboard bias regulator, low side current sensing, adjustable osc freq., adjustable trip current. All through hole components.
Power supply: +-35VDC to +-75VDC (25A), 12VAC (2A) aux supply
1 Pair IRF(x)4227/ IRFB4127
IR2110/IRS2110/FAN7392
HEF4069
LF356N/TL071
PCB Size 3 x 4.7"
T157-2
Power measurements to follow.
An Iraudamp1 derivative. Onboard bias regulator, low side current sensing, adjustable osc freq., adjustable trip current. All through hole components.
Power supply: +-35VDC to +-75VDC (25A), 12VAC (2A) aux supply
1 Pair IRF(x)4227/ IRFB4127
IR2110/IRS2110/FAN7392
HEF4069
LF356N/TL071
PCB Size 3 x 4.7"
T157-2
Power measurements to follow.
Attachments
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Deleted member 148505
As suggested by AN-978 application note. I've made the source of the high side mosfet and the drain of the low side mosfet very close to each other, so I minimize the pcb track between them as much as possible. That's why the footprint of the inductor is compromised.
This is one of its early prototypes. I improved it by using some of the information in IR's Design tips.
Sample video on first power up. I connected it to my JBL GT5-12
JLAmp1000D - YouTube
Attachments
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