i want to build a amp with 1-4 Transistor MAX!! -very simple

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what ARE you looking for then?
listen to people's advice, you're not going to build a power amp with just a handful of 3055's. it takes more than stringing together a few devices to make a usable, let alone good-sounding, amp.

incidentally, my Rega Brio uses a single 2955/3055 output pair and it sounds very nice, puts out about 35Wpc (at least 50Wpc in the custom version i built w/beefier power supply). but it also uses 3 other transistors for driver/bias and an opamp (TL072/AD711) for the input circuit.
 
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i want amp like the pic but with 2N3055 an 2N2955...
simple OK?!
and not with 9V, but with 30v/40v/50V...
and wath the power that is out?? (with 50V)


Resistor 470
Resistor 5.6K
Resistor 3.3
Resistor 1.5K
Resistor 22
Capacitor 1000uF
Capacitor 47uF
Diode 1N4148
Transistor 2N3053 x2
Transistor 2N2905
 

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what exactly is the purpose of using so few transistors (besides design/construction simplicity)? even very simple circuits can be difficult to master, there is more than meets the eye.
why not just use an LM3886 IC or something? if you are looking for the easiest possible solution, that is the way to go. it will sound OK too, not fantastic but respectable, and probably much better than the circuit you are suggesting.
 
The closest thing I can think of to what you want would be a "cool follower" ( http://www.geocities.com/ResearchTriangle/8231/my/Cool_Follower1.GIF ). As seen it'll give 100W RMS into an 8 Ohm load supposedly. You could probably scale it down to 4 transistors by only using two power transistors... But even then it would have to be driven by a voltage stage (preamp that can swing the voltage needed). I never built this design but the author has some other really nice designs so I trust it to be descent.

But really, why not just get some new transistors, some are really cheap, and you'll need more passive components then active anyways, so they're not the majority of the cost...
 
Sorry, I don't have the program you mentioned, but it is a simple design and you can tailor it to your needs easily. I did play around with simulations of this circuit and other simmilar to it in switcherCAD III and is pretty leanient to transistor substitutions.

Why not give it a go yourself, you'll learn a bit as well. As for using an opamp, I don't know exactly what you mean, if you mean for voltage gain, then by all means use one if you want, it would be very simple indeed to do.
 
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