TOPIC:

What should be the Q factor of shelving filter for baffle step compensation?

www.trueaudio.com/st_diff1.htm

hello aczern,

the effect of the baffle step depends on diameter of your speaker, the position of the speaker on the baffle, the baffle width and height and last but not least the influence of your listening room.

So there is not the typical baffle step that couldbe compensated.

To compensate the baffle step you have to know the effect first. Best way to do is to measure your speaker. If you do not have the equipment to do a spl measurement you can simulate the baffle diffraction for example with a program called "the edge" (free download under www.tolvan.com).

If you know the effect of your baffle diffraction it is simple to compensate it via minidsp.

your link, first graph: something like : Filter:high shelf, 300hz, Gain:-6dB, Q:0.8

The baffle step is not only a slope to lower freq. but also a peak at the beginning of the baffle step, that has to be corrected too! (very simple with minidsp: select a notch filter ( called peak))


by the way: the baffle step begins, where the wavelength starts to diffract around the baffle edges , so this starting point could be calculated very simple: Bafflle step start = c/(baffle width *2) where c is 344 m/s. , baffle width in mm, baffle step start in hz. From this point of view it is not always clever to design a very slim baffle. Example: baffle width 180 mm, baffle step starts at 960 Hz, baffle width 400mm, baffstep starts at 430 Hz.

enough for today and a happy new year to the minidsp community

best regards ctm57555

aczern,

To duplicate a simple analog circuit like the one you referenced, the Q setting should be 1.0.

Dave.

Thanks!