Recent content by dr_mick51

  1. D

    Watt for speaker and Watt for power consumption, Class D and AB

    That's the multi-million dollar question. And no for the TPA3255 Aiyima A07 . It requires minimum 18V, (the TPA3251 Aiyima A04 can work with 12V). You can use a 18V 1A power supply. You will be using 5-6W on the amplifier itself and power losses, plus 2W (1W/ch) And you still have room for more...
  2. D

    Watt for speaker and Watt for power consumption, Class D and AB

    The amplifier consumes 5-6W in quiescent state itself. That means only 1-2 Wats are really audio output power.
  3. D

    Watt for speaker and Watt for power consumption, Class D and AB

    That's right. 2V^2/8ohms(impedance)=0.5W. Cheers.
  4. D

    Watt for speaker and Watt for power consumption, Class D and AB

    He is using a 50Hz audio signal which probably the driver is not able to reproduce properly, hence you don't listen it very loudly. But the woofer is moving like crazy. Playing that signal at that power longer might break it. If the guy was supposed to use a 1kHz tone instead , he might be deaf...
  5. D

    Watt for speaker and Watt for power consumption, Class D and AB

    Did you measure speakers resistance at the driver terminals, or the speaker binding post? If you measure at the speaker binding post and your speakers have woofer and tweeter then you only measuring resistance of the woofer only(most likely). The tweeter has a capacitor in series which will not...
  6. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    Again. That's because we really don't need much power to begin with. My "recommendation" (i'm not saying is really needed) for those people who want more "power" instead of buying a bigger power supply (which will do little to nothing to increase the output volume with a input signal of 0.2V) it...
  7. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    Just be careful and don't plug many things to it. I saw the terrifying pictures from the reviews. I suspect they overloaded it.
  8. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    Nice videos. I haven't watched them before. Interesting that his amplifier comes with thermal pads, because my Aiyima A04 comes with a copper shunt 1.5-2mm aprox and the 2 plastic washers/standoffs. I replaced the white thermal grease it came with and replaced it with a Thermalright one. Just...
  9. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    That's nice. I might even buy one for myself. My old Kill-a-watt is almost dying. Just remember to take a baseline measurement which you will substract from your future measurements while playing music or pink/white noise to calculate your actual power used as output power.
  10. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    Wattmeters only tell you how much power is drawn from the mains. You need to measure the amp On with 0% on the pot and then playing music. Also remember the power supply has power losses, the amplifier to operate consumes power for the other functions. Even the chip consumes power while on...
  11. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    The problem is that music is very dynamic but you can see the multimeter and determine a max voltage value and an "average" from your observation. Don't try tones. Tones are way louder than real music. Not helpful to calculate average power for music. Now, for level matching you need to use...
  12. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    The top red ones are 0.1uF C0G or NP0 type. The yellow ones below are 2uF X7R ceramic type. The small green ones below are 1uF X7R ceramic type. The NP0 are bigger even being smaller in capacitance. On the power supply bulk capacitors I think I used 2x 2uF X7R and 1uF NP0 ceramic on each big...
  13. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    The reason is very simple my friend. Because not much power is been drawn by the amplifier. Most of the people use 1-2W most of the time. That's not enough to heat up too much the heatsink. And that has been my whole point since the beginning. We don't use as much power as we think.
  14. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    I'm not really sure about which capacitors you refer. Some electrolytic capacitors are in series to the audio path(those before and after the opamps). For those you use 0.1uF (1% of the capacitor you want to bypass) ceramic NP0 or C0G dielectric type 50V. For the other electrolitycs you can use...
  15. D

    AIYIMA A07 TPA3255 Review (Amplifier)

    You mean the ones on the back of the PCB? I believe that for the bulk power supply capacitors the bypasses are 10, 2 and 0.1uF. The bulk capacitors (1000-3000uF) help to smooth the ripple, for the small spikes(noise) you need small capacitors with a very quick discharge time instead.
Top Bottom