Hi,
there are ae few magic R´s:
R46/47 (original HIfizen schematic) 4k7
Output to ground resistors (30-100 Ohms)
Lowering R46/47 and to lesser effect the output to ground resistors will meke the absolute dc offset lower and more closely controlled.
The disadvantage is that going below 4k7 for R46/47 will slowly worsen the sound quality and lowering the output to ground resistors will waste quite some power wich could go to the speakers.
I tried some different configurations (different current sources, zeners thermal coupling etc.) and described them in a thread wich I will try to find and post.
William
there are ae few magic R´s:
R46/47 (original HIfizen schematic) 4k7
Output to ground resistors (30-100 Ohms)
Lowering R46/47 and to lesser effect the output to ground resistors will meke the absolute dc offset lower and more closely controlled.
The disadvantage is that going below 4k7 for R46/47 will slowly worsen the sound quality and lowering the output to ground resistors will waste quite some power wich could go to the speakers.
I tried some different configurations (different current sources, zeners thermal coupling etc.) and described them in a thread wich I will try to find and post.
William
http://www.diyaudio.com/forums/showthread.php?postid=856975#post856975
here it is,
and one more:
http://www.diyaudio.com/forums/showthread.php?threadid=80315
hope this helps
William
here it is,
and one more:
http://www.diyaudio.com/forums/showthread.php?threadid=80315
hope this helps
William
Hello everyone,
winter is coming soon here but the good news is that now I have more time to
work on my stuff.
I've powered up my aleph-x for the first time since a few months to play around with my DC offset problem.
I notice something wierd, if I short the input to adjust the offset I get a descent level of DC. But when I try it without shorting or with something feeding the input I'm getting around 3V between binding post cold and about 1.5V after an hour.
Is that a normal behaviour to get such a difference short input versus not short?
Thierry
winter is coming soon here but the good news is that now I have more time to
work on my stuff.
I've powered up my aleph-x for the first time since a few months to play around with my DC offset problem.
I notice something wierd, if I short the input to adjust the offset I get a descent level of DC. But when I try it without shorting or with something feeding the input I'm getting around 3V between binding post cold and about 1.5V after an hour.
Is that a normal behaviour to get such a difference short input versus not short?
Thierry
wuffwaff said:Hi,
you will need two capacitors of the same size to connect plus in and minus in.
If using it unbalanced you´ll have to connect minus in via the capacitor to ground.
William
That might be the problem, I was only using capacitor on the + side, - going directly to the ground. Can't wait to try it tonight.
What would be the right capacitor value to use? And what type?
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