New Cellphone Headset Cuts Background Noise, Improves Voice Clarity
One of the benefits of cellphones is that they allow you to make calls from anywhere you can get a signal. One of the downsides of that freedom is that you often find yourself calling from noisy environments -- sidewalks bathed in traffic sounds, airports bombarded with crowd noises and public announcements -- that can make the call nearly inaudible.
Now, a small Silicon Valley start-up company called Aliph has come up with a solution: a new cellphone headset that suppresses background noise dramatically so that your voice comes through loud and clear even in the most clamorous settings.
This new "adaptive" headset, called Jawbone, goes on sale for $150 starting today at the company's Web site,
www.jawbone.com. In its first incarnation, it works with many, but not all, phones from Motorola, Nokia and Sony Ericsson. Versions for other phones are in the works.
Aliph's Jawbone technology, which grew out of research the company did for the Pentagon, relies on two kinds of microphones. Standard microphones transmit your speech and detect background noise. A special contact microphone, which rests against your cheek, uses vibrations in your bones to determine exactly when you are speaking.
This latter mike, which Aliph calls a "voice activity sensor," allows the Jawbone headset to distinguish your voice from background noises much more accurately than a normal cellphone headset can.
Aliph's Jawbone
Like many other acoustic systems, the Jawbone includes special chips and software that attempt to enhance voice frequencies and reduce background frequencies. But because the contact microphone lets the device know precisely when you are speaking, it is able to apply these digital filters more efficiently and successfully.
To accommodate the multiple mikes, the Jawbone's design is quite different from most headsets, which aim to be almost invisible. The Jawbone is light but large and quite visible, with a shiny aluminum piece that extends from your ear to your cheek. On one end of this prong is an earpiece, and on the other end is the contact mike that rests against your face. There's also a second part, a control unit that clips to a shirt or belt, or can tuck into a pocket or purse.
A few months back, at The Wall Street Journal's D: All Things Digital conference, Aliph unveiled the Jawbone with a dramatic live demonstration. Company officials showed the device suppressing the noise of a boombox, a blender and a weed whacker only a couple of feet from a phone. But over the past few days, I have been testing it myself in more real-world conditions.
Using a Sony Ericsson T610 phone on the AT&T network, I have tested the Jawbone in an airport; in a plane on a tarmac; in a car with an open window cruising down a freeway; and in the presence of rock music cranked up all the way.
Because the Jawbone control unit has a switch that turns its noise-suppression technology on and off, I was able to run comparison tests on every call and confirm that Jawbone made a big difference. In every case, the people I was calling reported a sharp decrease in background noise and a sharp increase in the volume and clarity of my voice. Jawbone also improved the quality of the incoming audio on my test calls.
At Dulles Airport near Washington, D.C., the sounds of a moving sidewalk, other people and constant announcements nearly drowned out my voice. But when I turned the Jawbone on, those noises were reduced to a dim background hum. In a taxi on a San Diego freeway, with the window cracked open a few inches, the road noise and wind were a big distraction, but they faded to almost nothing when I turned on the Jawbone.
The only situation where the Jawbone wasn't as impressive was in the plane on the tarmac, with people streaming down the aisle, flight attendants making announcements, and the blower overhead blasting air onto my face. In that case, the Jawbone did cut the noise, but the air from the blower still created a sort of static-like sound that made the call very annoying to the person I had dialed.
There was one big problem. On most of my test calls the people on the other end reported an echo effect -- they could hear their own voice echoing back at them. I didn't hear this, but it's obviously a major annoyance. Aliph says this isn't common and speculates that it might be due to the phone or network rather than the Jawbone. But when I removed the Jawbone and just used the phone normally, the echo went away. If this is a common issue with the headset, it will have to be fixed.
There are some other downsides to the Jawbone. The two-part design can make you feel as though you're wrapped in wires -- from the phone to the control unit and from the control unit to the earpiece. Aliph says it is working on a wireless version, but for now the wires are a problem.
Worse, the earpiece was uncomfortable, and I doubt I could wear it every day for long periods. You might have a different reaction.
I don't recommend the Jawbone for every person in every situation. But if you are comfortable with headsets and often find your cellphone calls disrupted by noisy environments, the Jawbone could be a huge help.
新式耳机有效屏蔽噪音
手机带给我们的一个便利是能够让你在任何有信号的地方打电话。但是你在享受这种自由的同时也会遇到一个问题：在很多情况下你发现自己在一个嘈杂的环境中打电话－－在车辆行驶噪音不绝于耳的人行道上，在人声鼎沸的机场－－令对方几乎无法听到你的声音。
现在，矽谷一家小型初创公司Aliph提供了一个解决途径，该公司推出的一个新式手机耳机能够大幅降低背景噪音，即使在最嘈杂的环境中，你的声音也能够清晰而响亮的传递到电话的另一端。
这种新的“适应型”耳机名为Jawbone，从9月9日开始在其公司网站
www.jawbone.com上出售。首批推出的耳机可应用于摩托罗拉(Motorola)、诺基亚(Nokia)、索尼爱立信(Sony Ericsson)等多种手机。适用于其它手机的耳机目前仍在研制中。
Aliph的Jawbone技术的渊源是该公司为五角大楼所作的一项研究，这种技术依赖两种麦克风：标准型麦克风传送你的声音并探测出背景噪音；另外一种特殊的接触式麦克风紧贴你的面颊，根据你骨头的震动准确的测定你何时在说话。
Aliph将后一种麦克风称之为“声音传感器”，与普通手机耳机相比，使用这种技术的Jawbone耳机能够将你的声音与背景噪音进行更精确的区分。
像许多其它传音系统一样，Jawbone耳机内含有特殊晶片和软件，它们能够增强语音频率并降低背景声音频率。但是由于接触式型麦克风能使设备准确地感知到你何时在讲话，因此这些数字滤声器可以得到更有效和成功的应用。
由于有两个麦克风，Jawbone的设计迥异于大多数的耳机，一般耳机的设计理念是尽量“隐形”，而Jawbone尽管很轻但体积较大，比较惹人注目－－一个闪亮的铝质支架从你的耳朵一直伸到脸颊。这个支架的一端是一个听筒，另一端是紧贴脸颊的接触式麦克风。另外还有一个控制部件，它可以夹在衬衫或皮包的带子上，也可以放在口袋或钱夹里面。
数月前，在《华尔街日报》(The Wall Street Journal)的一个论坛上，Aliph首度公开了Jawbone，并做了生动的现场演示。该公司高层人士向人们展示这个设备能够消除距离手机仅几英尺远的内置扬声器、搅拌机以及割草机的噪音。但是在前些日子，我在更真实的条件下对这个设备进行了测试。
我使用一部索尼爱立信T610手机在AT&T网络上对Jawbone进行测试，测试地点分别是机场、停机坪上的飞机、在高速公路开窗行驶的汽车、不间断播放摇滚乐的场所。
Jawbone的控制部件有一个开关，能够开启或关闭噪音消除功能，因此我能够在每次通话时进行比较测试，结果证明Jawbone的确能够极大地消除噪音。在每一个测试低点下，与我通话的人都表示在通话过程中出现背景噪音大幅降低、我的声音音量和清晰度大幅提升的情况。在我的测试中，Jawbone还改善了通话另一方的声音质量。
在华盛顿的杜勒斯机场，移动人行通道、周围人群以及持续不断的广播几乎淹没了我的声音。但是当我打开Jawbone，这些噪音下降成为柔和的背景声音。在行驶在圣地牙哥高速公路的计程车上，我将车窗开了一部分，公路上的噪音和风声对我的通话造成了很大的干扰，但是当我开启Jawbone时，这些噪音几乎完全消失了。
Jawbone表现唯一不尽人意的是在停机坪上的飞机中，当时乘客沿著通道缓慢走出，乘务员在不停的进行广播，头上的鼓风机将空气吹到我的脸上，这时Jawbone确实消除了这些噪音，但是鼓风机吹出的风仍然产生出了一种类似无线电噪声的声音，与我通话的人感觉这种声音甚为恼人。
测试中发现了一个很大的问题。在我所进行的大多数测试中，电话另一端的人都说存在回音现象－－他们能够听到自己声音的回音。尽管在我这边没有听到回音，但是显然这种现象令人很是不快。Aliph说，这不是一个普遍现象，并揣测可能是电话或网络的问题，而不是Jawbone的缘故。但是当我关闭Jawbone按正常方式通话时，回音就会消失。如果这是Jawbone耳机的一个普遍问题，它必须得到解决。
Jawbone还有其它一些不足之处。这个耳机由两部分组成，这种设计让你感觉自己好像被线缠绕了起来－－从手机到控制部件，从控制部件到听筒都是线。Aliph说，它正在研制一个无线版本，但是目前线仍然是一个问题。
更糟糕的是，听筒感觉起来很不舒服，我都怀疑自己是否每天都能长时间的戴著它。不过，也许你的反应会与我不同。
我不推荐所有人在任何出场都使用Jawbone。但是如果你不在意戴耳机，并且你的通话常常因为嘈杂的环境而中断，Jawbone将会给你很大的帮助。
