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Influence of DC offset on bias

Hi everyone. I'm usually an observer here and hopefully learn something along the way. Can someone shed some light on my question of what if any influence or affect dc offset has on the bias of an amp. I know how to check both and have never come across an amp with identical offset on both sides; well within acceptable levels on both sides, but never the same. Also impossible to adjust them to the same level. Does this render identical bias on both sides incorrect in terms of channel balance as it affects your ears? I would greatly appreciate some insight into this.

Thank you
csontos
marakanetz's avatar
marakanetz
5,473 posts
 
An auto-bias bases is simply using a reverse conductivity of diode. Depending on how large your bias current should be you choose the diode with the same reverse conductivity current. It's all in the parameter list. There are certainly more sophisticated and advanced auto-bias supplies that allow to match upto 10% of parameter tolerance.
csontos OP
1,311 posts
 
Thank you. That explains why I was disappointed with the 559. 10% is huge. I can easily detect anything that's not identical. Maybe I should be "Golden ears". Pinpoint imaging and transient response and therefore detail absolutely depend on a perfect bias adjustment in relation to each channel being the same.
csontos OP
1,311 posts
 
Karakanetz, I appreciate your knowledge on this subject and I don't mean to pester you about this but does offset influence speaker sensitivity?
csontos OP
1,311 posts
 
OOps. Sorry, Marakanetz.
marakanetz's avatar
marakanetz
5,473 posts
 
Speaker sensitivity can only tag volume level difference of channels when you listen realy quiet. There also factors to mention such as stereo volume pot. Other than that it has nothing to do with speaker sensitivity.
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