anybody here built the p101 or heard one ? I would like to know the characteristics of its sound how clean is it what are the drawbacks
Would still need to be prepared to get some decent heat sinks...
Something large that will require some emissivity calculations and estimation, maybe look at some existing products to see what current they consume while idling vs the surface area of their heat sinking.
Something large that will require some emissivity calculations and estimation, maybe look at some existing products to see what current they consume while idling vs the surface area of their heat sinking.
I would put the power supply in an extra casing and just send the DC out to the actual amps. You will have lots of magnetic field and hum. Dont worry about stories, that DC is more lossy than DC, its not. Because there is no capacitive and inductive loss.
You need at least 10 000 uF each channel. Even at just ambient I seen the light bulb tester glowing a bit, when I increased the bass. And this while sitll just drawing 16 W. If there is no sound, my amp draws 14W. I got 2x10 000 uF each rail, means 40 000uF all up, and its 2 amplifiers, one right, one left.
Then put some small caps next to the power pins of what ever amps you use. TDA7293 I think can handle 80V, but 63 V is pretty much at its limit then. Better use transistors I guess. I found, already 6V peak to peak sinewave is really painful to listen to at 2m distance,
You need at least 10 000 uF each channel. Even at just ambient I seen the light bulb tester glowing a bit, when I increased the bass. And this while sitll just drawing 16 W. If there is no sound, my amp draws 14W. I got 2x10 000 uF each rail, means 40 000uF all up, and its 2 amplifiers, one right, one left.
Then put some small caps next to the power pins of what ever amps you use. TDA7293 I think can handle 80V, but 63 V is pretty much at its limit then. Better use transistors I guess. I found, already 6V peak to peak sinewave is really painful to listen to at 2m distance,
inductance is a bich 😀 i know from my other pcb designs and it can make a difference
differential routes are a proper way to solve some of this problems , and impedance matching can make a lot of difference to from the amp designs I've troubleshooted so much as a single trace under a condesator can meka the amp oscilate
differential routes are a proper way to solve some of this problems , and impedance matching can make a lot of difference to from the amp designs I've troubleshooted so much as a single trace under a condesator can meka the amp oscilate
was just thinking, 63 V you need 100V capacitors. At the end all that high voltage stuff costs more than buying low voltage trafo and low voltage caps, especially with elcos. Maybe several small elcos cost less than one big one for same capacitance. Multiple small ones would be better anyway, as then their resistances are in parallel.
If the whole thing is oscillating high frequency, maybe a bans pass helps just before the power transistors. If you use active, you may need poties as well, just put them near the power transistor input. Then any noise is reduced just there as well.
If the whole thing is oscillating high frequency, maybe a bans pass helps just before the power transistors. If you use active, you may need poties as well, just put them near the power transistor input. Then any noise is reduced just there as well.
Let's do some rough math: 45-0-45 Vac means about ±63 Vdc, which is good for about 200-250 W @ 8 ohms or 400-500 W @ 4 ohms. Efficiency of a class AB amplifier is about 66%, so the transformer would fit for a 4-channel amp with 8 ohms or a stereophonic one with 4 ohms speakers.
Best regards!
Best regards!
better put some LEDs in the capacitor banks. Then you know when its "life" plus it slowly discharges when powered off. Otherwise, when you are still testing, it takes a long time for the caps to discharge and you don't want to shorten them each time or discharge them via some resistors. Seems some stage I somehow zapped the inputs of the mosfets when disconnecting the capacitor bank and next time I powered up, the went up in smoke. Not much fun with a 15 pin IC.
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