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Forget any idea about stereo and bridged being related. BOTH channels are bridged and there is a good chance the bass output is also bridged. Bridging is a technique to split one signal into two paths, each passing through their own amplifier then combining them again at the loudspeaker. So there are two amplifiers for the left channel, two for the right channel and two for any other channel. It follows that the two wires to each lousdpeaker are both driven, one from each of the amplifiers making up one channel. That's the reason you can't ground one of the loudspeaker wires, effectively you link one amplifier output to ground and damage it.
Also forget any ideas about class-D being to do with stereo or bridging, it refers to the way the amplification is achieved and has nothing to do with the content of the audio, whether it is left, right, bass, mid or treble. You can have bridged amplifiers with any class of amplification although with some it makes no sense to do so.
Audioguru is right to criticize my comparator for not having reverse voltage protection although in reality the chances of it being damaged are very slight. If in doubt, add a small diode (1N4148 or similar, it isn't critical) from the input pin of the LM311 to ground with it's cathode (banded) end to the input pin. I deliberately made it as simple as possible, there are several ways to improve it but all make it more complicated.
Brian.
Also forget any ideas about class-D being to do with stereo or bridging, it refers to the way the amplification is achieved and has nothing to do with the content of the audio, whether it is left, right, bass, mid or treble. You can have bridged amplifiers with any class of amplification although with some it makes no sense to do so.
Audioguru is right to criticize my comparator for not having reverse voltage protection although in reality the chances of it being damaged are very slight. If in doubt, add a small diode (1N4148 or similar, it isn't critical) from the input pin of the LM311 to ground with it's cathode (banded) end to the input pin. I deliberately made it as simple as possible, there are several ways to improve it but all make it more complicated.
Brian.
