Hello everyone, I would like to know if you guys can clarify on what components alone or in conjunction determines the frequency response of an integrated amplifier.
- Is it the pre amplifier?
- Op amp?
- Output chips?
- Circuit board design?
Knowing that audible frequencies are in between 20 Hz to 20 Khz, is it possible to modify this? for example in a wider range?
Will this improve hearing experience?
Thanks for taking the time to read, all responses are welcome.
Have a great day.
SkyWay
- Is it the pre amplifier?
- Op amp?
- Output chips?
- Circuit board design?
Knowing that audible frequencies are in between 20 Hz to 20 Khz, is it possible to modify this? for example in a wider range?
Will this improve hearing experience?
Thanks for taking the time to read, all responses are welcome.
Have a great day.
SkyWay
Various components affect the frequency response of an amplifier e.g. valves and transistors have their own frequency limitations while capacitors and inductors change their reactance as frequency changes. Circuit board and/or wiring layout can affect frequency response due to the introduction of stray capacitance and inductance.
The components in, and topology of, an amplifier are selected with the required frequency response in mind.
It is quite possible to extend the frequency range beyond audibility or we wouldn't have radio frequency (RF) amplifiers!
The components in, and topology of, an amplifier are selected with the required frequency response in mind.
It is quite possible to extend the frequency range beyond audibility or we wouldn't have radio frequency (RF) amplifiers!
It's a matter of choice by the design engineer. Generally, the earlier stages of a system should have
the dominant effect on bandwidth limits. However, as HK said in the 60s, a wider frequency response
in the electronics does improve the sound.
If you use a turntable, that and the phono stage will usually determine the bandwidth limits.
If you use a CD player, that will usually determine the high frequency bandwidth.
the dominant effect on bandwidth limits. However, as HK said in the 60s, a wider frequency response
in the electronics does improve the sound.
If you use a turntable, that and the phono stage will usually determine the bandwidth limits.
If you use a CD player, that will usually determine the high frequency bandwidth.
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It's complicated to explain.
Lets say you take an integrated amplifier and look at the line input stage.
From the socket, through the input switching and wiring the signal arrives at the line stage electronics which might be a simple buffer or a low gain stage.
That first part of the journey has limits set by any stray capacitance and the inherent capacitance of any screened cables but it is way higher than anything audio related. Lets say it could cope with DC through to several megahertz.
The line stage may be an opamp. That will have a response of DC to a figure dependent on the opamp but it should be much higher than 20kHz.
That is not necessarily good design though. We don't want to amplify DC and so we add an input coupling cap. That sets a lower limit for that stage in combination with line amp input characteristics.
The high frequency response should be deliberately limited too. The designer will attend to that using different techniques. There may be a filter at the input to the line stage to limit the high frequencies that can enter the amplifier and the the line stage itself may be limited by adding components to the feedback network for that stage.
The power amp follows similar lines in design. That may further limit low frequency response and also high frequency response. The power amp may struggle (by economies of design) to be able to deliver full power at frequencies much above the 20kHz you mention.
In those cases it is good practice to ensure that such signals can not even get as far as the power amplifier so that it doesn't try and do something it was not designed for.
So there is no simple one size fits all.
Lets say you take an integrated amplifier and look at the line input stage.
From the socket, through the input switching and wiring the signal arrives at the line stage electronics which might be a simple buffer or a low gain stage.
That first part of the journey has limits set by any stray capacitance and the inherent capacitance of any screened cables but it is way higher than anything audio related. Lets say it could cope with DC through to several megahertz.
The line stage may be an opamp. That will have a response of DC to a figure dependent on the opamp but it should be much higher than 20kHz.
That is not necessarily good design though. We don't want to amplify DC and so we add an input coupling cap. That sets a lower limit for that stage in combination with line amp input characteristics.
The high frequency response should be deliberately limited too. The designer will attend to that using different techniques. There may be a filter at the input to the line stage to limit the high frequencies that can enter the amplifier and the the line stage itself may be limited by adding components to the feedback network for that stage.
The power amp follows similar lines in design. That may further limit low frequency response and also high frequency response. The power amp may struggle (by economies of design) to be able to deliver full power at frequencies much above the 20kHz you mention.
In those cases it is good practice to ensure that such signals can not even get as far as the power amplifier so that it doesn't try and do something it was not designed for.
So there is no simple one size fits all.