the speaker makes significat wobbles and the circuit works fine on 19V instead of the 25V (im using an laptop charger as the power source, the power from it is suprisingly clean) one thing to note would be to heatsink the resistor or use two 11 ohm ones in series.
now im geniuenly intrested in how to get rid of the pop noise and to built out a little power supply for it
I am usually interested in trying to use a battery power supply. Things keep changing with batteries over the decades and now circuits do better (longer) with them too. I couldn't say though running class A.
The 'pop' noise will be due to the output AC coupling capacitor, this is the nature of single voltage rail designs and is best mitigated with a time delayed relay before the speakers.
If you plan on using a voltage regulator you should calculate the heat dissipation of the regulator, you could use a low dropout regulator or a CFP/darlington configuration if the losses are unacceptable.
Do you have a up-to date circuit schematic we can see?
no i dont since i didnt make any changes to the circuit, other than a diffrent transistor (irf540 or even the irf740) but im considering dropping the supply voltage to 15V
One of the best and easiest ways might be simply to place a normally closed relay across the headphone output (a DPDT type) wired so the output is shorted to ground. A simple FET driver then powers the relay opening the contact after a delay set by the value of a cap.
This gives around a 6 second delay. Supply in red and relay current in green.
If your supply is only 15 volts or so then you can leave it out. It just limits the gate voltage for much higher rail voltages. Its not critical, Any Zener of between say 6v8 and 12 volts is fine.
If you used an IRF510 (and pretty much any similar type MOSFET would be fine) then the gate voltage limits for that FET are -/+20 volts. So you can omit it.
If you used an IRF510 (and pretty much any similar type MOSFET would be fine) then the gate voltage limits for that FET are -/+20 volts. So you can omit it.
i think ill just leave out the relay thing its more trouble than its worth, also there are these headphone jacks with a switch that activates when you put your headphones in, maybe that could just activate the relay on its own?
No relay needed. Just plug your headphones after a few seconds with the volume down. I think that the headphone jack that you are referring to is made to cut off the signal beyond the headphones when they are plugged in.
You would need a bleed resistor on the output to provide a path to charge the cap before plugging the headphones in.
if i were to lower the supply voltage to 15V could i just swap R3 with R4, and lower R2 to 1ohm? also how should i integrate a volume control potentiometer? one of my ideas for the second one was to have a jfet buffer to make sure that the input capacitor of the amp dosent join with the one of the source and start doing weird things.
I would not go any lower with R2. R3 would need to be lowered to turn the FET on more with a lower supply. 22k works in the simulation.
No need for a buffer, and you can scale R3 and R4 up by a factor of ten. The DC conditions will remain the same. Just add a 22k or 47k pot at the input, nothing more is needed.
No need for a buffer, and you can scale R3 and R4 up by a factor of ten. The DC conditions will remain the same. Just add a 22k or 47k pot at the input, nothing more is needed.
A long time ago I designed this- https://www.diyaudio.com/community/...distortion-headphone-amp.163224/#post-2121121
The circuit is usually met with laughter and derision, but it performed well measurement-wise and sounded great.
The circuit is usually met with laughter and derision, but it performed well measurement-wise and sounded great.
So what is wrong with that circuit? The point you made, it sounds great. Why should you even care what others comment unless they can prove of a better option. Every time someone shows what he deems something great he made or designed, you will always find some ******** trying to bash it and never made anything of his own. Don't let others intimidate you - if you are happy is all that counts.
That's fine. Just be aware that simulation and real world can be a bit different and so be prepared to alter one of the bias resistors to get around half the supply voltage on the FET drain. You can increase those resistors now to 220k and 680k with no change to the biasing. If you do that you raise the input impedance which could be worthwhile.