[gerG]

The question comes up again and again (I paraphrase): "What headphones offer serious isolation and good sound quality?"

The answer is always canal-phones, but they are not always acceptable or practical. The PXC-250 are a nice design, but they do not go nearly far enough, either in cancellation range (they actually make low frequency noise more obvious) or in sound quality. This leaves Bose as the sole player in this area. Considering that they can't make their product fast enough to meet demand, I think there is a market for something better. Sennheiser has the technology and the capability to do better. Please help us meet this need.

To get the discussion stirred up, here are some design criteria:

15 db of isolation across the entire audible spectrum. This includes the deep bass (down to 20 hz at least).

Sound quality on par with the DH280 pro, or better.

Transportable, but not necessarily pocket-able. Compatible with a briefcase or carry-on bag is sufficient.

Circum-aural. Supra-aural cans adulterate my hearing too much, and they are almost impossible to get a consistent seal.

Electronics module detachable for transport. The PXC-250 is a real pain in this regard.

Price: $200 street price would have the wallets resonating around here.


As a first cut the HD280 with the electronics from the PXC250 seems obvious. In fact, I am willing to bet that Sennheiser has already tried it. What were the results, and can I try out the prototypes? My office is a real challenge with a very broad and active noise spectrum (don't fault me for trying guys

).

That is my take on the topic. Now for input from my fellow head-philes, many of whom are banished to noisy cubicles for most of their waking hours.


gerG

 

[commando]

Agreed. Even if someone just sold the noise cancellation unit, but it'd probably have to be paired with a specific headphone to work well.

 

[PorkRind]

A couple of points regarding gerG's post:

The Bose QC2's appear to be readily available. Bose has them available on-line, they're selling them at kiosks in major airports, and Hammacher Schlemmer ships them out the day you order them. I ordered mine on a Sunday and got them on a Friday.

And I don't believe you'll see full audio spectrum noise cancellation any time soon; there's not a lot that can be done to attenuate higher frequencies other than passive NR.

I would love to see someone give Bose some serious competition, though. Mine didn't cost me any cash (I redeemed Marriott Reward points to get them), but I would've had a tough time justifying 300 bones out of pocket.

 

[commando]

The QC2's pretty expensive though. Does the QC2 sound better than the QC1? I had a listen to the QC1 and it was terrible: absent highs and boomy overemphasized bass. They worked very well for active noise canellation though - but like you say only for bass frequencies.

 

[taylor]

Why not DIY it?

I'll throw in my $0.02 - most of the noise cancelling systems are poorly designed. They mount the microphone on a small, pocketable box. But your ears are not in your pocket. A good noise cancellation headphone would need a microphone on each ear, along with a two channel noise canceller.

A noise canceller is fairly simple to rig up, you just wire up microphones to the inverting input of on op-amp and mount one on each earcup. Would also be very cool for binaural recording.

 

[oneeyedhobbit]

Not all circumaural phones are difficult to get a seal with--the Sennheiser PX 250s do have a small cup, larger designs are not at all difficult.

 

[Leporello]

Quote:

Originally Posted by gerG As a first cut the HD280 with the electronics from the PXC250 seems obvious. gerG

Seconded!


Regards,

L.

 

[Daroid]

What about the HDC-451 ?
Sennheisers problem currently isn't technology and implementing noise-cancelling circuitry, see - http://www.sennheiser.com/sennheiser...n_active-noise
But I agree with you, they need to offer more consumer models at competitive prices.

 

[PorkRind]

Quote:

Originally Posted by commando The QC2's pretty expensive though. Does the QC2 sound better than the QC1? I had a listen to the QC1 and it was terrible: absent highs and boomy overemphasized bass. They worked very well for active noise canellation though - but like you say only for bass frequencies.

I never had a chance to audition the QC1s, but I did do a lot of research before placing my order. The general concensus was that the QC2's are an improvement on the QC1's in a number of areas, and one of those areas is sound quality.

I don't find the bass "boomy;" it seems fairly well defined. As far as the rest of the listening experience is concerned, I would say that (barring canal-phones), you probably won't find better sound quality with any headphone in the noisy environments presented by most planes, trains and automobiles. They're not what I'd call "bright" headphones, but there's so much noise pollution in the upper frequencies from the surrounding environment that any detail would be lost regardless.

I'm on a plane 8 - 12 hours each week, and find the experience much less fatiguing with the QC2s.

If you live in an area where the QC2s are available at a retail location (or fly through an airport with a Bose booth), try them out. Bring your own music source, though; the demo material Bose provides isn't particularly useful in evaluating them (Kenny G style MOR pap; apologies to any taste-impaired Kenny G fans).

 

[pank2002]

And for those who dosen't read german: http://www.sennheiser.com/sennheiser...n_active-noise

I've only listed to the BOSE QC2 very brief, and I didn't think they were that great for noise canceling, but on the other hand I haven't heard the PX250.

It seems sennhesier even have a NoiseGuard (TM) used by the HMEC 300 and 400, so I guess I would just be a question of implating a cheaper version of the technology into a normal-customers-headphone. Or you could just get a HMEC 400... it's only like $625

 

[gerG]

Those HMEC25 look interesting. The issue with that series (besides the price) is that they are made for vocal communications, not music. Very risky. The big tanks are too large for the office, and have too much isolation.

I am looking for a product that offers more value than the Bose product. My mistake on the availability. They were still scarce when I was looking at them.

The pxc-250 have the microphones inside the earcups, similar to the Bose. That would indicate a more sophisticated circuit than a simple out of phase mix of the external signal.

I will resort to DIY if nothing else shows up. I have a pair of pxc250 for parts. Unfortunately that does not help most of the people who need these headphones.

gerG

 

[Steve999]

Interesting post. I agree, the Bose QC2 is the best thing out there and it's not head-fi grade audiophile sound. There's a serious market niche wide open for $200 hifi comfortable noise reduction headphones. Major bucks to be made. Not little headphone audiophile market bucks, but major-league mainstream mass market bucks.

Quote:

Originally Posted by gerG This leaves Bose as the sole player in this area. Considering that they can't make their product fast enough to meet demand, I think there is a market for something better. Sennheiser has the technology and the capability to do better. Please help us meet this need. gerG

 

[acs236]

Do these active cancelling headphones provide more isolation than canal phones?

 

[Geek]

I haven't ever heard a closed headphone that isolated below about 200hz, except for canalphones. I've listened to the entire Ultrasone series, the Beyer DT250-80 and DT770-250, and the AKG K271S.

It's possible, but wouldn't it have already been done to some degree? I think the laws of physics are against the headphone listener in this case, mostly because ambient bass below 100hz is more felt than heard, and a headphone enclosure won't do much to stop rumbles from going through your bone structure and up to your ear.

Having said that, the Etymyotic series does a great job of isolating some of the lows; the very bottom end is basically untouched and can be heard in full.

I still don't see how it's possible to cut the ambient bottom octave down 10 to 15 decibels. You'd have to develop some weird "body enclosure" or something.

Cheers,
Geek

 

[bioxeed]

Quote:

Originally Posted by taylor Why not DIY it? I'll throw in my $0.02 - most of the noise cancelling systems are poorly designed. They mount the microphone on a small, pocketable box. But your ears are not in your pocket. A good noise cancellation headphone would need a microphone on each ear, along with a two channel noise canceller. A noise canceller is fairly simple to rig up, you just wire up microphones to the inverting input of on op-amp and mount one on each earcup. Would also be very cool for binaural recording.

You're showing your ignorance here as (at least in the pxc-250) there IS a microphone in each earpeice. Also, just inverting the signal you receive at the microphone there is totally unacceptable - you're going to end up cancelling the music as well as the noise. While it isn't impossible to DIY it's not nearly as simple as you think. People aren't doing their phd's on active noise cancelling just for fun.