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Bad quality sound on MoodeAudio 6.x
#52
To wrap up my involvement in this issue, I spent a fair amount of time last evening trying to understand the alsa eq10 plugin. I didn't learn much. There's too little documentation of the code.

However, here's an interesting tidbit from Eq.cc

Code:
PortInfo
Eq10::port_info [] =
{
    {"31 Hz", CTRL_IN, {DEFAULT_0, -48, 24}},
    {"63 Hz", CTRL_IN, {DEFAULT_0, -48, 24}},
    {"125 Hz", CTRL_IN | GROUP, {DEFAULT_0, -48, 24}},
    {"250 Hz", CTRL_IN, {DEFAULT_0, -48, 24}},
    {"500 Hz", CTRL_IN, {DEFAULT_0, -48, 24}},
    {"1 kHz", CTRL_IN | GROUP, {DEFAULT_0, -48, 24}},
    {"2 kHz", CTRL_IN, {DEFAULT_0, -48, 24}},
    {"4 kHz", CTRL_IN, {DEFAULT_0, -48, 24}},
    {"8 kHz", CTRL_IN | GROUP, {DEFAULT_0, -48, 24}},
    {"16 kHz", CTRL_IN, {DEFAULT_0, -48, 24}},

    {"in", INPUT | AUDIO},
    {"out", OUTPUT | AUDIO}
};

and similarly for Eq10X2 (two channels).

The numbers in this structure correspond to db values in an unexplained table found in the CAPS webpage.

I interpret it to mean that the default gain in an octave band is 0db, the minimum possible gain is -48db, and the maximum possible gain is +24db. (That's a huge variation in gain!)

There is a predefined "Flat" curve available for the graphical equalizer. The preset values there are 66 across the board. One might infer for this and the above that in this plugin the value 66 corresponds to 0db, the value 100 to +24db, and the value 0 to -48db. A small change would have a big effect.

Or maybe I'm just deluding myself. Tongue

Regards,
Kent
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Messages In This Thread
Bad quality sound on MoodeAudio 6.x - by Jedrek - 08-30-2019, 07:47 PM
RE: Bad quality sound on MoodeAudio 6.x - by TheOldPresbyope - 06-26-2020, 03:45 PM

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