Retronitus - Noise from the past!

12345679»

Comments

  • Well, after all, it is just a lil' beeper speaker. Kind of like some old computers have.

    Regarding the capacitor value, i'm not sure. Maybe 100uF ? With the pretentious audio-grade ones I used, that's the next step up. But 47uF certainly isn't terrible, as you can hear from my recordings.
  • JRetSapDoogJRetSapDoog Posts: 750
    edited October 31 Vote Up0Vote Down
    Maybe my filter is lame. With respect to the left channel in the schematic above, I only use surface mount decoupling caps (104's) for C4 and C5, and I use 180R instead of 750R for R20. Although I think there's a lot of variability on what values can be used, maybe my values and the cap type(s) are not ideal. Then again, it is mono and the speaker is small (though the beeps can be quite loud).
  • Here is the formula to calculate the 3db cutoff frequency
    f3db=1/(2*pi*r1*c1)

    For 19.4KHz the series R is 820 ohms and the capacitor to gnd is 10nF.
    My Prop boards: P8XBlade2, RamBlade, CpuBlade, TriBlade
    Prop OS (also see Sphinx, PropDos, PropCmd, Spinix)
    Website: www.clusos.com
    Prop Tools (Index) , Emulators (Index) , ZiCog (Z80)
  • Maybe my filter is lame. With respect to the left channel in the schematic above, I only use surface mount decoupling caps (104's) for C4 and C5, and I use 180R instead of 750R for R20. Although I think there's a lot of variability on what values can be used, maybe my values and the cap type(s) are not ideal. Then again, it is mono and the speaker is small (though the beeps can be quite loud).
    Your sound circuit works fine for the beeps it was intended for. I was probably silly to try to use it for this music software.

  • JRetSapDoogJRetSapDoog Posts: 750
    edited November 1 Vote Up0Vote Down
    Cluso99: Thanks for the formula. Guess that makes the 3dB cutoff for my current components (180R & 0.1uF) 8.84KHz. Sounds like there's room for improvement.

    David: Well, I had hoped that it would be able to play music, but I never got around to trying any.
  • David: Well, I had hoped that it would be able to play music, but I never got around to trying any.
    That's okay. It plays beeps quite well!

Sign In or Register to comment.