Triticum Agricolam Posted January 7, 2014 Author Report Share Posted January 7, 2014 Yeah the measurement was done on the assembly table in my wood shop, definitely not in the vehicle. To help isolate the output of the driver from the output of the port I just held a piece of MDF against the enclosure between them to block the sound. It worked better than I expected. The fact that I had the mic about an inch off the center of the cone probably helped too. "Nothing prevents people from knowing the truth more than the belief they already know it.""Making bass is easy, making music is the hard part."Builds: Link to comment Share on other sites More sharing options...
Triticum Agricolam Posted January 7, 2014 Author Report Share Posted January 7, 2014 How does the calibration file of that microphone look like? (on this site you can get it, I assume you already have it, because it looks like their program) It's a decent mic, but most microphone aren't very good below 50Hz. (even microphones 5X the price of yours) But it's good enough to get a decent reading, +- 5Hz I would guess would be the uncertainity. By the way if you are doing this for getting the best sound of the box, it's almost not worth it because your ears won't hear a 2-3Hz difference of tuning. It also matters where you perform this test, is it inside a car or house? The serial number of my mic is: 1381110 if you want to look at at the calibration file. I know I'll never hear the difference of a couple Hz but the quest for perfection is a large part of the enjoyment I get out of designing and building this stuff. "Nothing prevents people from knowing the truth more than the belief they already know it.""Making bass is easy, making music is the hard part."Builds: Link to comment Share on other sites More sharing options...
kirill007 Posted January 8, 2014 Report Share Posted January 8, 2014 Yeah the measurement was done on the assembly table in my wood shop, definitely not in the vehicle. To help isolate the output of the driver from the output of the port I just held a piece of MDF against the enclosure between them to block the sound. It worked better than I expected. The fact that I had the mic about an inch off the center of the cone probably helped too. I'm not saying the results are wrong, but you could test again making sure the subwoofer doesn't go above 50-55dB when taking port measurement. If you want to search how to do this scientifically, try to search for helmholtz resonator test. How does the calibration file of that microphone look like? (on this site you can get it, I assume you already have it, because it looks like their program) It's a decent mic, but most microphone aren't very good below 50Hz. (even microphones 5X the price of yours) But it's good enough to get a decent reading, +- 5Hz I would guess would be the uncertainity. By the way if you are doing this for getting the best sound of the box, it's almost not worth it because your ears won't hear a 2-3Hz difference of tuning. It also matters where you perform this test, is it inside a car or house? The serial number of my mic is: 1381110 if you want to look at at the calibration file. I know I'll never hear the difference of a couple Hz but the quest for perfection is a large part of the enjoyment I get out of designing and building this stuff. I looked at the calibration file but couldn't use it properly to read anything. I understand what you are doing, and that is quite enjoyable. I'm happy people still try to find how to do things properly. Thinking is the root of all problems... You ALWAYS get what you pay for. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.