Home Theater Systems - Electronics and Forum - HomeTheaterShack - View Single Post - Crossover question(s)
View Single Post
Old 02-09-07, 03:16 PM   #10 (Link)
 
brucek
Shack Administrator
Platinum Supporter
Alias: brucek
User: #6
Since: Apr 2006
Posts: 4,987
brucek is offline
Re: Crossover question(s)


Quote:
Honestly a crossover designed from a formula has very little chance of working well
I guess you could always use REW to check whether a filter worked properly as calculated.

If I loop a cable from output to input on my soundcard and then in REW clear C-weight and meter files, but leave the soundcard calibration file, then that loopback cable should measure a flat frequency response.

Then if I break that cable out so I can connect a passive circuit in series with the loop, I can plot its response.

I calculated a simple passive RC 1st order high pass filter with a C = 0.1uf and an R = 22K, I get a calculated -3dB down fc of 144Hz. So if I test at 75dB, the filter should show 72dB at 144Hz.

So I test it out (I tested 10Hz to 10KHz with a 512 sweep duration x4) and my results are 72.3Hz at 144Hz.

Pretty close...................

hpf.jpg

brucek


Forum Rules Reply With Quote