Hello to all
I manage to build a excellent class D amp with 500W RMS power on 4 ohms and 1000W RMS on 2 ohms
I also build a full bridge DC to DC converter to easily driving this bad boy
everything is ok when I connect amplifier input to an external audio device like: my moble, mp3 player,.. etc
but as son as I connect the amp input to the car stereo RCA there is a huge spark and the smps current rises quickly. I guest it's because the ground of smps input and output connect togather as the car stereo and smps are powering from the same power sourse (car battery)
so whats the solution here? how does all commercials amp works then? am I missing some circuit here?
Please help me fix this amp
I manage to build a excellent class D amp with 500W RMS power on 4 ohms and 1000W RMS on 2 ohms
I also build a full bridge DC to DC converter to easily driving this bad boy
everything is ok when I connect amplifier input to an external audio device like: my moble, mp3 player,.. etc
but as son as I connect the amp input to the car stereo RCA there is a huge spark and the smps current rises quickly. I guest it's because the ground of smps input and output connect togather as the car stereo and smps are powering from the same power sourse (car battery)
so whats the solution here? how does all commercials amp works then? am I missing some circuit here?
Please help me fix this amp
You need to strictly isolate 12 Vdc ground from signal ground, i.e. design a SMPS with a galvanically isolated xformer.
Best regards!
Best regards!
If there is a spark, it would appear that you have a source of voltage connected to the RCA shields.
Can you provide more information, diagrams, photos. We're working blind without some starting point.
Do you have a scope?
What's the DC voltage with the meter's black probe on the 12v ground and the red on the RCA shield?
Can you provide more information, diagrams, photos. We're working blind without some starting point.
Do you have a scope?
What's the DC voltage with the meter's black probe on the 12v ground and the red on the RCA shield?
It turns out that there was a connection between the heatsink of one switching mosfet and secondary winding of transformer( I figure this out by reading resistance between primary and secondary winding of transformer and it showed a couple of hundred kilo ohms on meter)
and after looking under the board I find the problem
After fixing the problem I install my smps to my car driving 500W class D amp(subwoofer) and two class AB amp with 200W each
you wouldn't belive the enjoyable ride I had with these badboys
Thanks for your help anyway
and after looking under the board I find the problem
After fixing the problem I install my smps to my car driving 500W class D amp(subwoofer) and two class AB amp with 200W each
you wouldn't belive the enjoyable ride I had with these badboys
Thanks for your help anyway
It's not a 1kW, 1kHz sine wave.
Low frequency bass can be very enjoyable at very high levels. The impact at that level is a fraction of what you'd get from a good massage. For me, 140dB is just about enough. Others need more.
Low frequency bass can be very enjoyable at very high levels. The impact at that level is a fraction of what you'd get from a good massage. For me, 140dB is just about enough. Others need more.
It's Absolutely RMS power that I meantioned, measured with oscilloscope😉
the PMPO of it would be 1200W @ 4 ohms and 2500W at 2 ohms
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I build a custom box for my subwoofer and all the amps that the top of the box is seperated for my amps.
a SMPS, Subwoofer amp 500W rms @ 4 Ohms or 1kw @ 2 ohms, 2 x 200W class AB amps for stereo music sound and a 2F capacitor
the sound quality is awesome and there is no distortions at the max volume.
I ran it yesterday for about 1 hour with full power outside the city and everything was good.
PS: Smps and all the amps are short circuit protected and also temperature protected with 2 setups: turn the fan on at 70 degree and shutdown smps at 100 degree in case there's a problem with cooling process.
I'll try to provide some pictures of the setups by the end of the week after I carpeted the box
a SMPS, Subwoofer amp 500W rms @ 4 Ohms or 1kw @ 2 ohms, 2 x 200W class AB amps for stereo music sound and a 2F capacitor
the sound quality is awesome and there is no distortions at the max volume.
I ran it yesterday for about 1 hour with full power outside the city and everything was good.
PS: Smps and all the amps are short circuit protected and also temperature protected with 2 setups: turn the fan on at 70 degree and shutdown smps at 100 degree in case there's a problem with cooling process.
I'll try to provide some pictures of the setups by the end of the week after I carpeted the box
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