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Old 10th December 2008, 09:48 PM   #131
AndrewT is online now AndrewT  Scotland
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Quote:
Originally posted by danielwritesbac
the PSU 0v connect right in the center of that stereo board.
The speaker return connect to the 0v output terminal of the power supply board?
try it and report your results.
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Old 11th December 2008, 02:16 AM   #132
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Quote:
Originally posted by AndrewT
try it and report your results.
Bit of "sink the mids" arrangement. Mine is operated parallel. I'm not sure about only using 2 of 220uF caps, except that stereo chips use only two caps. Are there additional components required for this?
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Old 11th December 2008, 03:59 AM   #133
sneih is offline sneih  Indonesia
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btw where is the signal resistor.... i wanna replace with MF resistor like riken/rodenstein?

thc
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Old 11th December 2008, 07:41 AM   #134
AndrewT is online now AndrewT  Scotland
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there are six small resistors on the PCB only the 10r connecting signal ground to power ground does not pass signal.
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Old 11th December 2008, 11:38 AM   #135
sneih is offline sneih  Indonesia
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thanks andrew!!
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Old 11th December 2008, 11:39 AM   #136
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Quote:
Originally posted by sneih
btw where is the signal resistor.... i wanna replace with MF resistor like riken/rodenstein?

thc
All of the pins of an op amp are a potential input.
Every part of a running amplifier has a signal, with the point being, to give it a direction.

Metal film is great at all-band rejection. So, it could be good for negative feedback.

Negative feedback (NFB): Everything is amplified with infinite gain--except for what you tell it not to do.

Confining your amplifier to the audio band will make it more powerful during the audio band, in that greater efficiency does have that outcome.

Therefore use metal film for feedback and input impedance. In the recent designs posted, those two resistors are 22k.

http://www.diyaudio.com/forums/attac...amp=1210693455 Click the link and see the picture by Peter Daniel, Audiosector, demonstrating that resistors against audio signal are metal film, but where greater isolation is needed, a carbon resistor is employed.
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Old 11th December 2008, 11:51 AM   #137
sneih is offline sneih  Indonesia
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Quote:
Originally posted by AndrewT


bring the two input pads to 0.1inch pin pitch.
bring the input end of the 22k Zin to outside these two input pins, but on the hot input side.
This gives a three pin input @ 0.1inch pitch. A computer type jumper plug (0.1inch pitch) can be used to short either pin to it's neighbour.
It also allows you to bypass the input DC block if you have DC blocking at the previous stage. Finally it allows you to short the AC input to signal ground for testing and setting up.
btw i m noob!!

that idea is hard to me to do!
maybe someone can realize that..
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Old 11th December 2008, 11:56 AM   #138
sneih is offline sneih  Indonesia
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Quote:
Originally posted by danielwritesbac


All of the pins of an op amp are a potential input.
Every part of a running amplifier has a signal, with the point being, to give it a direction.

Metal film is great at all-band rejection. So, it could be good for negative feedback.

Negative feedback (NFB): Everything is amplified with infinite gain--except for what you tell it not to do.

Confining your amplifier to the audio band will make it more powerful during the audio band, in that greater efficiency does have that outcome.

Therefore use metal film for feedback and input impedance. In the recent designs posted, those two resistors are 22k.

http://www.diyaudio.com/forums/attac...amp=1210693455 Click the link and see the picture by Peter Daniel, Audiosector, demonstrating that resistors against audio signal are metal film, but where greater isolation is needed, a carbon resistor is employed.

thx daniel, i have learns so much from you n others!!
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Old 11th December 2008, 12:09 PM   #139
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Quote:
Originally posted by sneih
thx daniel, i have learns so much from you n others!!
I think that I learn something every day. To me, there is some fun in getting to try them out and listen to what things do.
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Old 12th December 2008, 02:17 PM   #140
crt is offline crt  Indonesia
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how about this layout

[IMG]Click the image to open in full size.[/IMG]
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