Cool Dude Ted 9 Posted 6 hours ago 1 hour ago, MartinC said: For my check you didn't need to do anything with filters. Just directly compare the 5 measurements. It would have taken minutes. Can you post the SPL graph showing the 5 measurements with let's say 1/48 smoothing? Will do. Quote Share this post Link to post Share on other sites
Cool Dude Ted 9 Posted 6 hours ago 26 minutes ago, tuga said: Hi Stuart, I wouldn't use 1/6. Also, I would take care not to measure over an area wider than 30-40cm. You can also try testing standing waves using these test tones or those found on youtube and your iPad's SPL meter. Best, Ricardo Thanks for the reply. the 30-40cm area is related to the mic position? Also 1/6 is too much smoothing? Quote Share this post Link to post Share on other sites
MartinC 2,846 Posted 6 hours ago Note I only said 1/48 smoothing to see what's going on, not in relation to filter design. Quote Share this post Link to post Share on other sites
tuga 1,688 Posted 6 hours ago 31 minutes ago, Cool Dude Ted said: Thanks for the reply. the 30-40cm area is related to the mic position? Also 1/6 is too much smoothing? When performing MMM measurements I roughly move the mic inside an imaginary circle of around 30cm located where my head should be, and move it a bit front to back as well. I think that for EQ'ing room response 1/6 is too much. I use 1/12, some people 1/24 even. Quote Share this post Link to post Share on other sites
MartinC 2,846 Posted 5 hours ago 1 hour ago, tuga said: When performing MMM measurements I roughly move the mic inside an imaginary circle of around 30cm located where my head should be, and move it a bit front to back as well. Have you ever tried using a larger volume? As you may know Dirac Live uses an average over multiple points for the basis of its filter design, but here the points are recommended to be at a minimum spaced over a sphere of 1 m diameter. Quote Share this post Link to post Share on other sites
MartinC 2,846 Posted 4 hours ago @Cool Dude Ted I would though stop spending any time thinking about filter design or where you make measurements until you've actually been able to work out if you're getting meaningful measurements in the first place. Quote Share this post Link to post Share on other sites
tuga 1,688 Posted 4 hours ago (edited) 14 minutes ago, MartinC said: Have you ever tried using a larger volume? As you may know Dirac Live uses an average over multiple points for the basis of its filter design, but here the points are recommended to be at a minimum spaced over a sphere of 1 m diameter. I haven't. But moving that much forwards or backwards will make a massive change to the response and I am only correcting below 200Hz. I made these many years ago, side walls are asymmetrical as can be seen by the difference in the measurements. Edited 4 hours ago by tuga Quote Share this post Link to post Share on other sites
MartinC 2,846 Posted 4 hours ago 9 minutes ago, tuga said: I haven't. But moving that much forwards or backwards will make a massive change. It does indeed. It may be the Dirac range is more important for full-frequency range corrections but it's something to consider trying. Note I've done lots of corrections using single point measurements too so I'm not a strong proponent of any particular approach but I think it's a variable worth exploring. Quote Share this post Link to post Share on other sites
tuga 1,688 Posted 3 hours ago 42 minutes ago, MartinC said: It does indeed. It may be the Dirac range is more important for full-frequency range corrections but it's something to consider trying. Note I've done lots of corrections using single point measurements too so I'm not a strong proponent of any particular approach but I think it's a variable worth exploring. I would like to try Dirac or one of the more "evolved" response correction packages at some but I need to find out how to make them work with HQPlayer first. Quote Share this post Link to post Share on other sites
Cool Dude Ted 9 Posted 3 hours ago 1 hour ago, MartinC said: @Cool Dude Ted I would though stop spending any time thinking about filter design or where you make measurements until you've actually been able to work out if you're getting meaningful measurements in the first place. thank you. good advice. I will post the SPL graphs tomorrow but agree 100% that I somehow need to find out whether I can rely on the measurements being accurate. I’m concerned they may not be in which case my way forward would seem to be a USB mic which I am actively looking for. UMIK-1 seems to have a great deal going for it but none for sale 2nd hand that I can see. I think I need to bite the bullet, buy new and then sell on as I don’t plan on keep repeating this exercise. Thanks. Quote Share this post Link to post Share on other sites
MartinC 2,846 Posted 2 hours ago 1 hour ago, Cool Dude Ted said: thank you. good advice. I will post the SPL graphs tomorrow but agree 100% that I somehow need to find out whether I can rely on the measurements being accurate. I’m concerned they may not be in which case my way forward would seem to be a USB mic which I am actively looking for. UMIK-1 seems to have a great deal going for it but none for sale 2nd hand that I can see. I think I need to bite the bullet, buy new and then sell on as I don’t plan on keep repeating this exercise. Second hand UMIK-1s tend to sell quickly, which on the plus side means if you buy one and decide you don't want to keep, you should be able to sell it on easily without losing too much money. 1 Quote Share this post Link to post Share on other sites