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Old 2nd October 2008, 12:53 PM   #91
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Quote:
Originally posted by Dino-Indo
PCB view...

Simple PCB layout, several Riken RM resistors , one 0.7uH inductor paralleled with 10R 1 Watt resistor (at bottom side of PCB), Nichicon Gold 47uF, Nippon Chemicon 100uF...

LM3886 supply pins (at the bottom side) decoupled to ground with 3300pF Wima FKS and ground pin connected to central grounding with 22K Resistor... reducing the DC offset from 30mV to approx. 4mV....
Dear Dino, when you say that used the Ground Pin Connected to the Central GND with 22k Resistor, its used as you say to reduce the DC Offset? How you found that value? just start switching resistors and see wich is better?
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Old 2nd October 2008, 01:12 PM   #92
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Quote:
Originally posted by lanchile
lol,I know what you mean Vecino! if I can help you with something let me know.some parts can be very expensive like Black Gates caps I spent almost $150 just for the caps( I use them in my amp ...What a difference!). But some people use Panasonic FC caps with some good result.Good luck with your amp.

Where you purchase the BGs?

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Old 2nd October 2008, 02:22 PM   #93
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Quote:
Originally posted by samsagaz


Dear Dino, when you say that used the Ground Pin Connected to the Central GND with 22k Resistor, its used as you say to reduce the DC Offset? How you found that value? just start switching resistors and see wich is better?

Hi Samsagaz,

Thanks for your e-mail...
Well, honestly, I was doing that approach as 'trial and error'... all because of the low level hum when I first completed the kit.. I didn't specifically calculated that measurement.... but somehow it had effect on reduced DC offset....
Frankly, I hope it wouldn't affect the performance of the whole system of the LM3886 circuitry..

But FYI, I did not install the same resistor on my LM3876TF as well as my LM1875 gainclones.. hehehe.. all relying on the DC grounding circuit as suggested in Rod Elliot's website.. using a bridged rectifiers/diodes, one resistor (sorry, forgot the measurement) and one 10uF MKP cap...
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Old 7th October 2008, 08:50 PM   #94
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About bleeder resistors if not degrade the sound, i think that can use any brand , right?
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Old 8th October 2008, 01:46 PM   #95
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Yep...
I'm using regular resistor for the bleeders...
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