Blown or bad MOSFETs
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Blown or bad MOSFETs
Will blown or messed up MOSFETs in an amp cause it to clip? My Sony amp keeps clipping on me. Its a really old one that I didnt pay much for so Im wondering if its because the MOSFETs are going out on it and not keeping it cool.
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You are overdriving it, or else it is broken. If by clipping you mean sounds crappy, that could be anything in the system from the head unit to the speakers; if you put an oscilloscope on the input and found it clean but the output is clipping, you are likely overdriving the amplifier.
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If you have distortion through the entire volume range and it just gets louder you have a different issue than clipping. It might still be clipping, but more of the "something's broken" type rather than "I did not set up the system right or overdriving" type. If it is the latter continue reading:
I presume you use a headunit and an amp. It might not necessarily be your amp. You can get distortion between radio and amp as well if you turn your radio up too high. If you do not have an oscilloscope (which would be the best way to check) and clipping is related to overdriving the headunit or amp you could try the following:
First check for loose or broken wiring and the speakers are intact (especially the rubber between cone and speaker chassis). Then check the output ratings of your amp and headunit and the input ratings of your speakers and the used wires (thickness) and their (approximate) length. I would post the info with the names of the parts here before I continue with the things below, cause something might be damaged which might have been avoided just by looking at those figures.
1. Set the gain on the amplifier to minimum.
2. Turn up the radio until you hear the signal distorting. With most radios that should happen at around 80%.
That would be the threshold of your radio. In my headunit I can adjust the peak output of the radio so it does not get into the clipping range even at maximum volume setting. Check your headunits manual for that, because it is a good safety feature. Basically now you should have no clipping from the headunit.
3. If you need more volume you should set the radio at about ten percent below threshold.
4. Turn up the gain of the amp until you hear distortion. This should be way above your normal listening level.
5. Now turn down the gain a bit again so you do not get clipping until you reach your radio threshold.
Health issues:
Please be aware that listening to music that loud WILL lead to hearing loss - unless you bought a REALLY bad headunit and an even worse amp and you can still comfortably talk with a little raised voices with your passenger whilst listening to the music (should be around 80dbA at that distance between heads).
Good luck!
I presume you use a headunit and an amp. It might not necessarily be your amp. You can get distortion between radio and amp as well if you turn your radio up too high. If you do not have an oscilloscope (which would be the best way to check) and clipping is related to overdriving the headunit or amp you could try the following:
First check for loose or broken wiring and the speakers are intact (especially the rubber between cone and speaker chassis). Then check the output ratings of your amp and headunit and the input ratings of your speakers and the used wires (thickness) and their (approximate) length. I would post the info with the names of the parts here before I continue with the things below, cause something might be damaged which might have been avoided just by looking at those figures.
1. Set the gain on the amplifier to minimum.
2. Turn up the radio until you hear the signal distorting. With most radios that should happen at around 80%.
That would be the threshold of your radio. In my headunit I can adjust the peak output of the radio so it does not get into the clipping range even at maximum volume setting. Check your headunits manual for that, because it is a good safety feature. Basically now you should have no clipping from the headunit.
3. If you need more volume you should set the radio at about ten percent below threshold.
4. Turn up the gain of the amp until you hear distortion. This should be way above your normal listening level.
5. Now turn down the gain a bit again so you do not get clipping until you reach your radio threshold.
Health issues:
Please be aware that listening to music that loud WILL lead to hearing loss - unless you bought a REALLY bad headunit and an even worse amp and you can still comfortably talk with a little raised voices with your passenger whilst listening to the music (should be around 80dbA at that distance between heads).
Good luck!
