Am So 20. Juli 2008 schrieb Timo Jyrinki: > 2008/7/18 Hans L <[EMAIL PROTECTED]>: > > Just a guess here since I haven't even had a chance to look at these > > settings yet, but maybe the second frequency(after the @ symbol) > > represents the sample rate? So depending on the sample rate you are > > playing, you can set a different bass frequency cutoff? > > 2008/7/18 Joerg Reisenweber <[EMAIL PROTECTED]> wrote: > > Please refer to Wolfson WM8753 datasheet - link to be found on wiki > > I checked the datasheet. Indeed it means sample rate, but one that > scales. There's a table specifying eg. that if you select 100Hz > cut-off @ 16kHz, it means that at 48kHz the cut-off is 300Hz. I guess > the names in alsamixer have been chosen according to even numbers, so > that they actually really scale from lowest setting to highest. > > It's just that the scale seems to be opposite to reality, ie. the > highest cut-off frequency actually results in the lowest. Most > probably the setting I chose (200Hz @ 8kHz -> 1200Hz @ 48kHz) actually > represents 130Hz @ 48kHz, and the one named as such (130Hz @ 48kHz) is > in reality that 1200Hz @ 48kHz since it sounds so thinny. > > Problem solved, the cut-off is 130Hz which is quite high for > headphones but ok for portable speakers.
nah, this is +-3dB point - not exactly cutoff. so if you select 130Hz @ 48kHz and try to boost bass frequencies you get poor results, as there is only a boost of frequency below 130Hz. It's not reversed, it's just not cutoff frequency if you chose positive value for bass level. /j
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