My LM386 Speaks "D" ?

[Kenshin]

This maybe what is happening in my K1410 which has different rise/fall times

Besides: connect the 1 and 8 pin to get more gain, that makes a better comparator.

I had once thought of use LM386, but gave up this idea for it's too small.

Also considered LM301 (without internal frequency compensation), but it's too hard to get.

As to class-d, the slow rise/fall of switching speed creates non-linear transformation when PWM pulses are narrow. As a result, lower side gets clipped earlier then high side.

By altering the knee points of the non-linear transform, the sound of tube amp can be simulated. I know this is controversial, but I would like to give a hi-tech nick name to the tube amp ¡§Asymmetric Dynamic range Soft Limiter¡¨, ADSL in short.

Regards

Chen

 

[sychen0301]

Kenshin:

NI HOW !

I like your K1410. It is neat and simple. What is the freerun frequency it switches.

You are absolutely right about connecting p1-p8. I did try once and find no noticeable difference so I was lazy to wire it up again.

Is this K1410 your one-shot project or you have future plans on class-d. Since I am thinking of withdraw from the class-d. There is a small voice keeps on asking me ¡§Are you going to build a precision ADC+DAC capable of driving hundreds of watt and to run it at radio frequency, at home ? Are you able to do that ?¡¨

But I enjoy playing with this small LM386 for the past week.

Have fun DIY!

Regards,

Chen

 

[Kenshin]

approximately 200KHz @ quiescent.

 

[spare_parts]

I built this first posted circuit, and got a very loud popping sound, with a barely audible music signal somewhere way below it. Any suggestions? I bypassed the power supply with 100uf and .1uf. I tried putting the output cap both inside and outside the feedback loop.