Re: [LAU] [LAD] First release of jkmeter

Fons Adriaensen wrote: Hi, I was a little sceptical at first, but having read the article I think it's a great idea. My main concern was the magic number '83 dB(C)', which has somewhat vague, historic origin, but also I thought I would go deaf at that reference level. With two speakers, I guess that would be 86 dB(C). Quite interestingly, extrapolating the OSHA noise exposure limits down to that level, a person could endure that for up to 16 hours a day without hearing loss. That would make it, effectively, the loudest safe level for someone who mixes music all day, and so making the fullest use of the ear's comfortable dynamic range. (OSHA limits are detailed on http://www.elvex.com/facts07.htm ) As an experiment, I tried calibrating both of my monitor speakers with -20 dBFS pink noise to 83 dB(C). Sound at that volume doesn't feel comfortable to me. Perhaps I misunderstood something? Maybe I'm just over-sensitive to that volume, perhaps because I have neighbours here, don't have a house to myself, etc. Under the K-20 system, it seems the maximum SPL when monitoring with two speakers would be a scary 106 dB(C). Those monitoring levels would force engineers to keep loudness down, or risk going deaf otherwise. Presumably that would serve the intended purpose of the system, of avoiding excessive loudness of recordings, but I think it carries some risk. I think the K-14 system might be more to my own taste. I believe it keeps the 83 dB(C) reference level, but with peaks up to 100 dB(C) in a two-speaker setup. Sustained exposure for 2 hours even at the maximum level should still be safe as per the OSHA limits, but of course that level should rarely be reached anyway. I'd very much like to hear how a K-20, K-14, or K-12 recording compares to mainstream pop/rock/metal recordings. Perhaps the high reference level would feel more comfortable with program material that isn't so heavily compressed. I'm also curious to know what sort of monitoring levels other people have been using. I'd estimate that in the past I've been down to something like 60 dB as a reference level, and resorting to headphones when I felt more scrutiny was needed. This unfortunately seems necessary here because I have other people living around me. I'm looking forward to trying out the jkmeter implementation. And I imagine a K-14 and even K-12 version would be very useful someday. Regards, -- Steven Chamberlain steven(a)pyro.eu.org _______________________________________________ Linux-audio-user mailing list Linux-audio-user(a)lists.linuxaudio.org http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user