Oh I definitely would 😀 but its all relative. It is limited for a speaker and It all depends on the speaker impedance but the component values (the 22 ohm mainly) set a limit on output power.
off topic but im gonna start a thread on making an amplifier with germanium transistors i found.
I thought you meant vintage. So what would you say to why wanting to make it with PNP?
MP40
The answer is because you can
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An interesting side note, when you scrape the paint off an OC71, you can shine a light on it and the gain changes.
Sounds interesting, I have never experimented with germanium types before. Are you thinking pre-amp, headphone amp?
im back and ive done all the tests and the issues are:
-heat way to hot the capacitors get hot too
-too much power
-gets noisy with all my sources (probably a ground loop issue)
and the solutions are:
-get an piece of metal and screw all of the transistors on it, and glue the resistors.
-make the 22ohm resistors 47ohm
-a ground loop isolator/linear and an linear power supply
-heat way to hot the capacitors get hot too
-too much power
-gets noisy with all my sources (probably a ground loop issue)
and the solutions are:
-get an piece of metal and screw all of the transistors on it, and glue the resistors.
-make the 22ohm resistors 47ohm
-a ground loop isolator/linear and an linear power supply
The caps are right on top of the heat sink, they will get hot. What noise do you hear ground loops are hum not white noise. Found the fault, you left off the short white wire at the top right of the picture 😉
Besides all the problems you highlighted, can you comment on the sound that you hear, does it sound right.
If you don't need the voltage gain, I've used this circuit with various FET's before and never had a problem. It does not have any voltage gain, just current but it has much lower distortion and sounds great. It's a classic.
Source: https://sound-au.com/project83.htm
You mean glueing the resistors to the heat sink? you need thermal compound for good heat transference. When I made a similar circuit I ran 2x 5W resistors in parallel to share the heat between them.
In LTspice, If you hover the mouse cursor over a component, it will tell you the dissipation in the lower left.
the dissipation was 2W but these resistors seem to suck at their job and get way to hot way to fast.
Ahhh I remember the exact learning process your on 😉 just because a component is rated for a heat dissipation doesn't mean that's what you should run it at that rating constantly.
I like to run 5W resistors at 1W constant and for 1/4W at maybe 100mW.
TO-220 transistors start to need there own heat sink at about 500mW.
This probably various amongst opinion, but I like to keep things cool 🥶 and touch-safe.
I like to run 5W resistors at 1W constant and for 1/4W at maybe 100mW.
TO-220 transistors start to need there own heat sink at about 500mW.
This probably various amongst opinion, but I like to keep things cool 🥶 and touch-safe.
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