I have a amp which is connected to a premap and fed via ipod. The amp runs fine with no noticable distortion when running at low volume. However the sound starts to distort when the volume is increased.
I know there must be hundred reasons for this to happen. But what is the most probable reason. Inadequate power supply? or improper biasing ?
Any Inputs?
I know there must be hundred reasons for this to happen. But what is the most probable reason. Inadequate power supply? or improper biasing ?
Any Inputs?
As you say, many possible reasons.
You should look initially at where the volume control is located, and whether turning up the volume is causing overload of the following stages.
Biasing should not really change with volume, an inadequate PSU is a possibility.
This kind of problem takes seconds to pin down with a scope.
You should look initially at where the volume control is located, and whether turning up the volume is causing overload of the following stages.
Biasing should not really change with volume, an inadequate PSU is a possibility.
This kind of problem takes seconds to pin down with a scope.
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There is no volume control. Volume is controlled through the iPod.
The preamp is a simple emitter follower preamp. A single 2n2222 transistor. Nothing too fancy.
The preamp is a simple emitter follower preamp. A single 2n2222 transistor. Nothing too fancy.
So your problem could be anywhere in the chain from preamp to power amp. The only way to know for sure is to look and see with an oscilloscope.
You could also try without the preamp and feed the iPod direct into the power amp.
You could also try without the preamp and feed the iPod direct into the power amp.
Infed the amp directly from the iPod. The problem remains the same.
Also this circuit demands 60v supply. I be used a 48 v supply. Should this be the reason?
Also this circuit demands 60v supply. I be used a 48 v supply. Should this be the reason?
Excuse the typos. Posted using a mobile device. Also why can't I edit the previous post. Couldn't see a edit button.
We would have to know more details of the amplifier to guess whether a low supply is a problem.
You only have around 30 minutes to edit a post.
You only have around 30 minutes to edit a post.
That should be fine on a lower supply as long as point 'VA' is around one half of the supply voltage.
source of audio signal, choice of preamplifier and the way it was built , choice of an amplifier, PSU of an amplifier, choice of loudspeakers - each a part of possible problem. try to make more clear what you have in that chain. nothing new I have said now....
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