Date: Sun, 03 Jan 1999 20:03:32 -0600 From: Carlos Leon Subject: COZY: headsets In People's opinion. What is the MOST CONFORTABLE passive noise reduction HEADSETS available in the market ? Best Regards Date: Sun, 03 Jan 1999 23:05:45 -0500 From: Rob Cherney Subject: Re: COZY: headsets At 08:03 PM 1/3/99 -0600, Carlos Leon wrote: >In People's opinion. What is the MOST CONFORTABLE passive noise >reduction HEADSETS available in the market ? I'm happy with the Peltors. In addition, I've added the Oregon Aero temperfoam ear seals, which makes them even more confortable than the stock units. Rob- +------------------------------------------------------------------+ |Robert Cherney Home Phone: (410)465-5598 | |Ellicott City, Maryland e-mail: cherney@home.com | +------------------------------------------------------------------+ From: mikefly@juno.com Date: Mon, 4 Jan 1999 08:31:52 -0600 Subject: Re: COZY: headsets On Sun, 03 Jan 1999 20:03:32 -0600 Carlos Leon writes: >In People's opinion. What is the MOST CONFORTABLE passive noise >reduction HEADSETS available in the market ? > >Best Regards > > Peltor Mike Bowden From: sdbish@juno.com Subject: Re: COZY: headsets Date: Mon, 04 Jan 1999 12:16:52 EST >>In People's opinion. What is the MOST COMFORTABLE passive noise >>reduction HEADSETS available in the market ? >> After several years in the AF flying the big birds and wearing headsets, I personally had no problem with any brand, as long as if fit tight and shut out noise. My wife got me David Clark, with which I'm quite comfortable. On the other hand, my wife has trouble with anything on her head. She tried various types, including Telex and straight stereo headsets adapted, but was bothered by the clamping force after only short durations. Eventually the opportunity arose for her to try Peltor, and she was surprisingly satisfied, and greatly extended the time she would wear them. Peltor would definitely be her recommendation from someone who is quite sensitive to something on her head. Marv Bishop ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866] Date: Mon, 04 Jan 1999 09:57:28 -0800 From: Frank Johanson Subject: Re: COZY: headsets Carlos Leon wrote: > In People's opinion. What is the MOST CONFORTABLE passive noise > reduction HEADSETS available in the market ? > > Best Regards Dear Carlos, We found that one of the best things to do for our headsets is the sunglasses. The headset was pressing on the stems of the glasses causing a lot of discomfort. We purchased glasses from Zurich International, 500 Cohasset Road, Suite #34, Chico CA 95926 (USA) , phone number (916) 893-3657. They have a headband that can go in place of the earpieces (disattaches easily). This was great! To date we have bought several pairs each since we use them all year round. We keep a pair in the bag for our headsets and a couple pair in the cars. (Snow is a major brightness factor when driving around here in Maine). We bought our glasses at Oshkosh initially about 4 years ago. We have talked to them when we needed to replace stems, & ordered a pair. We then bought two more pair & the bands at OSH this summer. What a difference flying to OSH and flying home! Good Luck, Frank Johanson PS: We have a SoftCom Passive Noise Headset and 2 FliteSoft ANR headsets. When the plane is done, we will use those for the back seat & get new Boise for the front. Also, the Gel cushions are far superior to the foam ones. They can be bought searately and changed. Date: Sat, 08 May 1999 09:52:50 -0500 From: David Domeier Subject: COZY: Noise cancel headset?? Some of you guys must be using a noise cancelling headset. I'm in the market for one but don't know much about which is best for the buck. How 'bout sharing your opinion if you've got one. dd From: "John Slade" Subject: Re: COZY: Noise cancel headset?? Date: Sat, 8 May 1999 11:50:36 -0400 David, I have the new Pilot DNC. Its superb. No boxes or external batteries. So good that I was getting the rpms wrong for a couple of hours while I got used to the reduction in noise. A freind had the same model and it died. He sent it back and they replaced it by return mail. John Slade From: cdenk@ix.netcom.com Date: Sat, 8 May 1999 11:25:03 -0500 (CDT) Subject: Re: COZY: Noise cancel headset?? On 05/08/99 09:52:50 you wrote: > > Some of you guys must be using a noise cancelling headset. I'm in >the market for one but don't know much about which is best for the buck. > > How 'bout sharing your opinion if you've got one. > >dd > > > I have 3 of the original BOSE active noise cancelling, and are quite happy with them. After a long flight our ears are fine, and we talk in normal volume. Several years ago we tried the updated BOSE series II, and liked them, and put them on the low priority money list. At OSH last time we tried the BOSE series X. THe ear cups were more comfortable, and I believe the accoustics and noise canceling to be better, and the size is smaller. But the design of the headband has a spring loaded joint at the top of the cranium. The padding is poor, and is not comfortable, as a result they are not on our money list at all!. I fly with a friend safety pilot in a nice Mooney. He has experimented with just about every headset that is out there, spending more money than the Bose would cost. I prefer the Bose to all he has had, but my built-in interfaces aren't portable. When he's safety pilot in the Cosy, he used to bring his headset along, but now he uses the Bose. Date: Sat, 08 May 1999 09:37:44 -0700 From: Jeff Burhans Subject: Re: COZY: Noise cancel headset?? > How 'bout sharing your opinion if you've got one. Sure! I'm still a student pilot flying C150's, but I *LOVE* mine. I've got a SoftComm Phoenix (Model C-20) headset. I've used a bunch of different headsets (as a student of course, it's catch as catch can!) including some noise cancelling ones, and others not - this one is the most comfortable and clearest headset I've ever used.It does take a bit of getting used to as the engine noise is muted from what I was used to on the non-NC's, but that only took a flight or two.... Hope this helps some! * * *RION * Date: Sat, 08 May 1999 20:15:00 -0400 From: John Subject: Re: COZY: Noise cancel headset?? Hi Dave, I just bought a pair of Flight Com's ANR6 noise canceling headsets for $375.00 each from: http://www.airsource1.com I like them and the price is right. John Vermeylen N69CZ David Domeier wrote: > Some of you guys must be using a noise cancelling headset. I'm in > the market for one but don't know much about which is best for the buck. > > How 'bout sharing your opinion if you've got one. > > dd From: Jim Hocut Subject: RE: COZY: Noise cancel headset?? Date: Sat, 8 May 1999 21:30:47 -0400 I've had a question about noise cancelling headsets. I've never had the pleasure of trying any, so far my trusty David Clark's work just fine. What I've wondered is if noise cancelling headsets do such a good job of getting rid of noise you don't want to hear, wouldn't they also get rid of airplane noises that you really do want to hear. For instance, while instructing in a 172 a couple years ago on a dual cross country we started hearing a high pitched squeel from up front. The engine guages weren't showing anything wrong, but we elected to land at the nearest airport just to be safe. Once on the ground it was apparent we had made a good decision since the engine was spilling oil at an alarming rate because the seal for the generator shaft had torn up. Without having heard that noise we'd have been landing in pine trees miles from anywhere instead of at an airport. Jim Hocut jhocut@mindspring.com From: cdenk@ix.netcom.com Date: Sat, 8 May 1999 20:51:33 -0500 (CDT) Subject: RE: COZY: Noise cancel headset?? I was concerned with hearing important noises. I have on occasion lifted an earcup, or turned off the noise cancelling to check, and several times had noises occur (once was a magneto bearing inner race spinning on the shaft) that I had no problem hearing. I was warned about not hearing noises when I first started flying, kept an awareness. There are some noises you can hear better with the ambient blocked patially. I don't think it is a concrern with the first series Bose, or most others. I have had a mag go out, a fuel injector nozzle clog, a swallowed valve, and a prop bade split almost to the hub, a vaccum pump failure and I can assure in every instant, I had no problem noticing something was wrong almost instantly. There is a difference in sound, and its notieable. From: "John Slade" Subject: Re: COZY: Noise cancel headset?? Date: Sat, 8 May 1999 22:29:24 -0400 Jim, >wouldn't they also get rid of airplane noises that you really do want to hear. Marc Zeitlin (works for Bose) can probably answer this one better than me, but... I don't think so. You still hear all the noises. They're just not as noisy. Think of it as reducing a shout to a normal conversational volume. You actually hear it better. Makes distinguishing modulated tones (controller etc.) much much easier. Borrow one & try it. It might stop you getting tinnitus. I have even been known to use my DNC headset when mowing the lawn. Now if I could just get piped music... hmmm... John Slade Date: Sun, 09 May 1999 08:41:58 -0500 From: David Domeier Subject: Re: COZY: Noise cancel headset?? John, Thanks to you, Carl, Jeff, and all for the info. My current Telex units are 19 years young, still work, but capture every sound very efficiently and seem to make it louder. At 160 KIAS I can not talk to ATC. All they hear is airplane noise. I have to say "Standby while I slow up to Cessna speed". Re my engine break-in: yesterday I climbed to 12,500' from take off without an overheat. OAT at take off was 71°. The engine is definitely cooling down. Does anyone know a clew as to when the rings are properly seated? There sure is a lot of opinion on the subject but nothing definitive. dd From: cdenk@ix.netcom.com Date: Sun, 9 May 1999 08:45:56 -0500 (CDT) Subject: Re: COZY: Noise cancel headset?? was said Marc Zeitlin (works for Bose) can probably answer this one better than me, but...> Remember Mark is a mechanical engineer, you know stress, strains, forces, chasing things you can usually see, not electrons running around inside wire. From: Lee810@aol.com Date: Sun, 9 May 1999 11:34:43 EDT Subject: Re: COZY: Noise cancel headset?? In a message dated 5/9/99 7:50:38 AM Mountain Daylight Time, cdenk@ix.netcom.com writes: > was said Marc Zeitlin (works for Bose) can probably answer this one better > than me, > but...> > > Remember Mark is a mechanical engineer, you know stress, strains, forces, > chasing things you can usually see, not electrons > running around inside wire. Actually, Marc, whose major pet peeve is people spelling his name with a 'k' instead of a 'c', is formally trained as an Aerospace Engineer (from MIT, no less) but he's probably the best ME I met at HP. (Carl, when you quote from text that has his name spelled correctly and you misspell it ... all I can say is that I hope he doesn't kick you off the list :-). Acoustics and vibrations _are_ the domain of MEs so I'm sure Marc would give us all enlightenment if he didn't feel there might be a conflict of interest since he now works for Bose. I am a licensed EE and I can tell you that I know very little about the world of active noise cancellation. It's conceptually very simple, but I'm sure to put it to practice, it's frighteningly complex. As for the original questions about hearing the high pitch squeal, remember that ANR headsets do all their work below 300 Hz and a squeal is _well_ above that range. Above 300 Hz they rely on the passive components like foam to dampen the sound and that works the same as a regular headset. Missing audible cues from an engine that is misbehaving is a topic comes up so regularly it might make sense to commission a study to see if ANR headsets work as well or better than conventional headsets in allowing you to detect these acoustic anomalies. Lee Devlin Date: Sun, 09 May 1999 12:58:22 -0400 From: bil kleb Subject: Re: COZY: Noise cancel headset?? cdenk@ix.netcom.com wrote: > > At OSH last time we tried the BOSE series X. [..] The padding is poor, and is > not comfortable [...] mary tried them this spring: they went back before the 30 days were up. noise reduction was superb; comfort was lacking. -- bil From: cdenk@ix.netcom.com Date: Sun, 9 May 1999 15:52:37 -0500 (CDT) Subject: Re: COZY: Noise cancel headset?? My apology to Marc, for misspelling his name, spelling hasn't been my greatest claim to fame. When I was in 1 or 3 grade area, my name was quite a teasing point, where the kids, including the class bully had much fun. I quickly learned to be very tolerant. Also if I was out of place with Marc's M.E., wasn't thinking of accoustics, all the M.E.s I deal with are either machine design or HVAC. Of course we could go back in history when there was only 2 types of engineers, military and civil, with the mechanicals and the electricals branching off near the beginning. Agree with the comment mic near the lips. The Bose does a very good job of enabling a clean transmission, they have light foam wind muffs that I secured with a small black tyrap. Re: high pitched squeel, thanks for reminding me that when the sould waves get short, its literally impossible to do any correction with the active, its all passive. In that case, you would hear the high pitch more easily since the low pitches are antenuated. Date: Mon, 10 May 1999 08:55:08 -0400 From: Paul Krasa Subject: Re: COZY: Noise cancel headset?? I have two different types of ANC headsets in my flight bag. Two headsets were converted using the kits advertised on Sport Aviation; the other one is a Lightspeed 20K. The Lightspeed is superior in noise canceling and comfort to the converted headsets, but not by much. I borrowed friends noise canceling headsets (Bose, David Clark, Telex, and Lightspeed). I choose the Lightspeed because it was the most comfortable and had as good of noise canceling as the others. My non calibrated ears could find little difference in the quality of the noise canceling, but I could tell the difference between a 15db ANC headset and a 20db ANC while flying. Another issue to consider is headset clearance to the canopy. If you are tall like me, the one Inch of head clearance will be the foam pad at the top of some of the new headsets. One of the reasons I bought the Lightspeed instead of the Bose, is I had to bend my neck to close the canopy of my Long Ez. Not a situation conducive to flying. If you already have a headset you like, convert it over to ANC. The conversion takes less than an hour per headset. I have converted over a number of friends headsets, and can now do one in about a half hour. The difference between my converted headset and my Lightspeed 20K is comfort. Paul Long EZ 214LP p.s. Project Status: High speed taxi is going well. A few growing pains here and there, but nothing major. Just about ready for the "big one." Weather has been the big delaying factor has been either IFR or winds in excess of 10kts. Yesterday morning the winds were calm, and I was able to "fly" the canard down the runway, and held the same attitude for the whole run. Next, wing rocks with the canard flying. At 09:52 5/8/99 -0500, David Domeier wrote: > Some of you guys must be using a noise cancelling headset. I'm in >the market for one but don't know much about which is best for the buck. > > How 'bout sharing your opinion if you've got one. > >dd > > > Date: Sun, 9 May 1999 11:28:17 -0400 From: Bill Theeringer Subject: COZY: Microphone noise ....... All they hear is airplane noise. I have to say "Standby while I slow up to Cessna speed". Dave and all; I am using the Bose series I, but before that I had the stock David Clarks. I have 2 ham stations on board, world wide HF and 300 mile radius VHF. I am routinely complimented on the excellent quality of my transmitted audio by other amateurs (as well as controllers) who are lifetime radio operators. Most are amazed to find out that I am in an airplane. There is a secret to having this quality of transmitted audio. The secret is to minimize the signal to noise. Signal being defined as your voice and noise being everything else. I went through considerable testing to arrive at an optimum combination and it worked out to be the following: Turn the mike gain control on the back of the mike down as low as it will go. Add a 27 ohm resistor across the mike lead to ground. This can probably best be done inside the plug, although I did mine in the panel. ALWAYS have the mike virtually touching your lips and at an angle to the side. If the mike moves one inch away your voice will be very weak. As weak as the background noise you have just minimized. I used resistance and capacitance decade boxes while flying to arrive at the best combination while communicating with a local blind ham (a piano tuner) for the best results. Bill Theeringer N29EZ See our award winning Long EZ with Jim Newmans excellent retractable gear at http://www.flash.net/~infaero/infgear.htm Composite Aircraft Accessories PO Box 21645 Santa Barbara, CA 93121 HOME: 805-964-5454, SHOP: 805-964-5453 Date: Mon, 10 May 1999 22:25:40 -0400 From: "Marc J. Zeitlin" Subject: COZY: Noise reduction headset functionality Lee Devlin wrote: >Actually...... Thanks, Lee, but if I got bent every time someone misspelled my name (Marc OR Zeitlin), I'd be a basket case by now :-). >Acoustics and vibrations _are_ the domain of MEs so I'm sure Marc would give >us all enlightenment if he didn't feel there might be a conflict of interest >since he now works for Bose. I thought Carl's comment was a bit strange, but I can certainly understand the sentiment. I'm NOT an acoustic engineer (and don't play one on TV), but I have learned a lot about ANR headsets during my 10 months here at Bose. I'll be happy to expound on the theory and practice, and I'll keep the advertisements to the "zero" level asked for in the Charter. >As for the original questions about hearing the high pitch squeal, remember >that ANR headsets do all their work below 300 Hz and a squeal is _well_ above >that range. Above 300 Hz they rely on the passive components like foam to >dampen the sound and that works the same as a regular headset. This is basically correct. ANR technology (ANYONE'S - not just Bose's) works by placing a microphone inside the earcup and listening to the noise that gets through to the inside. An attempt is made to place the microphone as close to the ear as possible (without actually putting it inside the ear, although that has been attempted also) so that it will "hear" just about what the ear does. The electronics then take that signal, create a signal equal but 180 degrees out of phase (the opposite "sound", in other words) and then pipe that back through the speaker (driver, or transducer, in technical terms). Since the driver produces sound waves equal and opposite to the "noise", the noise is cancelled out. The NAV/COM/Radio signals are passed through the driver without being cancelled, so you still hear them clearly. That's the theory, anyway. In practice (as Lee points out) this only works at the lower frequencies - from 10 Hz up to the low 100's of Hz - I believe our ANR starts rolling off (becoming less effective) around the 200 Hz point, maybe a bit lower. As the frequency rises and the sound waves get shorter, it's less possible to cancel the noise by sensing with a microphone that isn't IN the ear - the "sound" produced by the driver will do a very good job of reducing the noise exactly at the microphone, but not so good of a job at the ear (which is, of course, what WE care about :-) ). Now, in any case, the "cancellation" is not perfect, hence the term "noise reduction", not "noise cancellation". Good ANR headsets can reduce the noise level by 15 - 20 dB or so in the frequency range described (varies by design and by frequency). Since it is the lower end of the frequency range that does the most to interfere with communication intelligibility, this is the range that is most important to cancel (not to mention the damage that it does to your inner ear). One problem that can occur in very loud aircraft is that the "driver" in the earcup is trying to create as much noise (but opposite) as is getting in the earcup. At high sound pressure levels, the driver will "clip" (just like your speaker at home, when you turn up the volume too loud to listen to the Grateful Dead :-) ) and it will create nasty cracks, pops, and other noises. One difficult issue in designing these headsets is trying to mitigate this problem and have the headseat gracefully stop cancelling noise, without making it too obvious. It is also critical for any ANR headset to have an excellent seal against the head. Hair, glasses, hats, big ears, misadjustments, sweat, etc. can have large effects on the quality of noise reduction. As far as PASSIVE noise reduction goes, all headsets work about the same. Create a large airspace around the ear, keep as much sound out as you can with a seal, and absorb the high frequency energy that does get in with some absorbent material - usually foam or the equivalent. For the most part, the larger the enclosed space, the better. So, what was the question again? :-). In your standard Cessna 150 or functional equivalent, the noise in the earcup at the ANR frequencies will be in the 100 dB range, so that after reduction, the noise will be in the 80 dB range. This is much lower, but far from inaudible - actually, it's still pretty loud. I think that it is highly improbable that (with the current crop of ANR headsets, or into the forseeable future) any noise would be reduced to the point that it would be inaudible, or even hard to hear. It will just be less painful. At passive frequencies (those above 200 Hz or so), the noise reduction is also in the 20 dB range, so the same comments apply. As Lee stated, squeals are at higher frequencies, while the lower frequencies include rumbles, propeller resonances, etc. If it were ever possible to reduce the noise levels to the 60 dB range or below, the concern over missing noises might be reasonable (like missing your oil pump bearing failing in a Cadillac). I'm not holding my breath until this level (20 dB lower than present, both in ANR and passive frequencies) is attained :-). With respect to comfort (Carl and bil both remarked on it), all I will say is that this is extremely personal, and I would recommend that you not buy ANY headset (active or passive) without trying it, at least for a few hours, and preferably for the 30 day period that more than a few of the manufacturers now offer. Also, different headsets fit differently and use more or less headroom. You just have to try them out to see if they work for you. -- Marc J. Zeitlin mailto:marcz@ultranet.com http://www.ultranet.com/~marcz/ Date: Sat, 14 Aug 1999 16:27:52 -0400 From: Gregg Perry Subject: Re: COZY: ANR Headsets cdenk@ix.netcom.com wrote: > Comfort is part of the picture. How is your hearing protected, difficult to measure, but one unscientific way is after a 4 > hour flight, do you speak in normal volume to the line boy when getting gas. The Bose allows that. Carl, 1) Look up the word "subjective" in the dictionary 2) Reread my post. Gregg Perry