Switched mode power supply and audio amplifier

[bibo1978]

switched mode audio amplifier

I have done a class B audio amplifier, and used a switched mode power supply as the input feed supplu for the amplifier, I have a problem with the amplifier when a steep change in the output occurs the switched mode supply fails to supply the amplifier with appropriate sink current, how may I avoid this problem?
Is the switched mode power supply a good idea to apply to audio systems?

 

[TonyCoimbra]

adjustable switched-mode power supply 80 amp

The last generation of amplifier are made with this system, the problem you have is that the power suplly doesn't have enough power, the solution is to get a more powerfull supply, or choose other supply with transformer.


Regard's
Tony Coimbra-PT :lol:

 

[bimbla]

audio amplifiers switched-mode supply

Yes you can have SMPS to supply power to Audio amps.
Failure to deliver currents in bursts means that you have to increase the capacity of the reservior capacitors.

Why did you feel the need to make a class-b amp for audio? ( Or did you mean class-d?)

bimbla.

 

[bibo1978]

I am using a class B amplifier because it is more linear, is there any other way rather than increasing the reservoir capacitor?

 

[bimbla]

Class-B is characterised by cross-over distortion!
How are you handling this?

bimbla.

 

[bibo1978]

I am using thermally coupled diodes at the base of the transistors as well as a adjustable resistor I am dissapaiting alot of power and running at a high Q point

I don't have a problem with that I care about quailty.

 

[bimbla]

What is the power you are looking at?

This will enable us to freeze on the best choice.

bimbla.

 

[bibo1978]

I need an average of 80 watt amplifier which can handle peaks as high as 1000 watts, can a switched mode power supply offer this, can the reservoir capacitors simply solve such a problem ?

 

[bimbla]

I need some info:

Where do you encounter a situation where the ave. reqd. is 80W and peak req. is 1000W?
Reservior caps need to be large, that is for sure.

I would suggest that you use a compressor ahead of the volume control to tackle this situation.

bimbla.

 

[bibo1978]

Large audio amplifier with 4 ohm subwoofers

 

[bimbla]

Two inverted fast diodes across the o/p transistors connectec from the o/p to the supply rails (in case of split supply) will also be a good idea.

bimbla.