I saw this at Facebook at https://www.facebook.com/share/p/1YitRKKmxy/
Can burn loudspeaker and transformer due DC flowing
Dc quite probably saturates transformer core-> lots of distortion and very little sound
Even if works the transformer is expensive and limits sound quality
Very low impedance sound input is less than 30 ohms – which means this circuit does not work properly with most sound sources, should be driven with an amplifier!

2 Comments
smashy road says:
Very low impedance sound input is less than 30 ohms – which means this circuit does not work properly with most sound sources, should be driven with an amplifier!
car games says:
Due to its extremely low impedance sound input of less than 30 ohms, this circuit requires an amplifier in order to function correctly with the vast majority of audio sources.