On 2/7/2010 3:21 AM, Bill W4ZV wrote: > "High isolation headphones" below means ~30 dB isolation from ambient noise. > Heil does not make any in this range and most active noise reduction > headphones (e.g. Bose) only have 10-15 dB. Here are some examples of what > Barry meant: > > http://www.extremeheadphones.com/ex-29.html > http://www.sennheiserusa.com/private_headphones_dj-headphones_004974 > http://www.etymotic.com/ephp/er6.aspx > > These are all available in the $75-100 range. > Yes. I work in pro audio, and have owned two sets Etymotic ER4 in-ear headphones for nearly ten years. I first bought them to use in my live recording work, where I'm mixing a jazz band in the same room with the musicians, and they're often playing pretty loud. The isolation can be quite good, in the 30 dB range that Bill talks about, but it depends on how well they fit your ears. The standard fittings are quite soft, and they happen to fit my ears very well. Every person's ears are different, and some need custom "ear molds" from an audiologist for the ultimate isolation.
As I've gradually slowed down my pro audio work, I've ramped up ham radio and when I got back on the air in 2003, the Etymotics almost immediately found their way into my ham shack. They're quite comfortable, and I can wear them for a long time. The real question is, ":how much isolation do you need?" When I'm working a SSB contest, I'm very happy with the sound, comfort, and isolation of the CM500 headset, but I haven't used it yet in a multi-multi operation. I suspect it will perform pretty well. 73, Jim Brown K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html