Tda 2050+bd249/bd250c

[Alek]

Hi! I've got this schematic with TDA2030+BD243A/BD244A which is suppose to deliver 40W rms at 4Ohm load with +-22V. So I have these spare parts in my junkbox: chip TDA2050 and BD249C, BD250C. Can I just use those instead TDA2030+BD243A/BD244A or should I change some capacitor/resistor values. Also, how much of volt supply would that circuit need and ofcourse how much Watts it could deliver, what do you guys think? Since the pic below is of low quality here's the parts list regarding from left to right on the schematic:

C1=2,2mF(16V); R1=47kohm; R2=1k8; D1,D2=1N4148; R3=47kohm; C2=47mF(16V); R4=1k8; R5,R6=2,2 ohms; C4, C5 and C6=100nF; C7,C8=22mF(40V), R7=1ohm;C3=220nF, and protection diodes are 1N4001.

[sakis]

well that is an inderesting issue ....

i wanted to play with a thing like that long ago from very long memory i can tell you a few things

tda 2030 + Bd249+250 is a lofi application BUT !!! its is an amlifier that is extremelly stable plays reliably has amazing drive abilty for a cr**py circuit ...weird loads is absolutely no prob to drive but quality is low ....

a memory also says that 2050 doesnt work like that but i am not sure
a memory also says that i dont recall seeing something like that with symetrical rails ( that should be a performer !!!!! )
a memory also says that some testing ive done in the past is that this type oF chips either stand alone or with external transitors eventhough may produce very high peaks of power the internal protection will not allow abuse ... AND HIGH POWERS ALSO ....

eventhough that topology technology and part ology is from the far away past a topic like that would be very interesting given the simplicity of the circuit ...

even now days there is room for a cheap lofi application ....

[Alek]

Thanks for the reply Sakis. As for the LoFi applications; well, first of all- it doesent have to be hifi anyway, coz I'm planing that circuit for an upgrade to my diy practice guitar amplifier that I've built some years ago, and that amplifier includes the TDA2030 in its circuit, so I'm hesitating between just swapping the TDA2030 fir 2050 or including the BD240/250 somehow and giving it a bit more output, just for the fun's sake