Darius Wey
02-23-2006, 05:00 PM
<img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-00.jpg" /><br /><br /><b>Product Category:</b> Bluetooth Audio Accessories<br /><b>Manufacturer:</b> <a href="http://www.bluetake.com/">Bluetake</a><br /><b>Where to Buy:</b> <a href="http://www.bluetake.com/where_to_buy.htm">Multiple Distributors</a><br /><b>Price:</b> i-PHONO mini Bluetooth Stereo Headphones - US $98.95; i-PHONO mini Bluetooth Stereo Transmitter - US $60.95; i-PHONO mini Bluetooth Headphone and Transmitter Combo Pack - US $150.95.<br /><b>System Requirements:</b> Any Bluetooth-enabled media device supporting A2DP (for stereo audio playback), AVRCP (for wireless remote control functionality), and/or HFP/HSP (for hands-free mobile communication). Where a Bluetooth-enabled media device is not present, the i-PHONO mini stereo transmitter will enable A2DP support, or A2DP/AVRCP support with a compatible iPod.<br /><br /><b>Pros:</b><li>Small, lightweight, and looks great;<br /><li>Well-designed transmitter;<br /><li>Support for USB charging;<br /><li>Excellent audio quality.<b>Cons:</b><li>Noticeable background hiss in HFP/HSP mode;<br /><li>Lower than expected operating range.<b>Summary:</b><br />You're sitting on a train. The man next to you is reading a newspaper. The woman next to you is having a short nap. You're bored. Really bored. So, being someone who loves a good tune, you take out your Pocket PC and load your favourite album. But you don't want to disturb the surrounding passengers, so you rummage around in your bag looking for your headphones. After a few seconds, you find them, but they're tangled! Ugh. Knots everywhere. You then spend the next few minutes untangling the mess.<br /><br />Sound like a daily event for you? Then you might need a Bluetooth headset such as the i-PHONO mini. Read on for the full review. <!><br /><PAGEBREAK><br /><span><b>An Introduction to A2DP, AVRCP, HSP, and HFP</b></span><br />A lot of today's consumer electronics are equipped with Bluetooth, and on top of the core specification is a set of defined profiles which determine a particular usage model. These profiles are defined within a stack (or a set of drivers). A2DP, AVRCP, HSP, and HFP are four profiles which fit in the context of this review. The following is an overview of each of the four profiles, which can also be found <a href="http://bluetooth.com/Bluetooth/Learn/Works/Profiles_Overview.htm">here</a> in its entirety:<br /><br /><b>Advanced Audio Distribution Profile (A2DP)</b><br /><i>"A2DP describes how stereo quality audio can be streamed from a media source to a sink. The profile defines two roles of an audio source and sink. A typical usage scenario can be considered as the "walkman" class of media player. The audio source would be the music player and the audio sink is the wireless headset. A2DP defines the protocols and procedures that realize distribution of audio content of high-quality in mono or stereo on ACL channels. The term "advanced audio", therefore, should be distinguished from "Bluetooth audio", which indicates distribution of narrow band voice on SCO channels as defined in the baseband specification. This profile relies on GAVDP. It includes mandatory support for low complexity subband codec (SBC) and supports optionally MPEG-1,2 Audio, MPEG-2,4 AAC and ATRAC. The audio data is compressed in a proper format for efficient use of the limited bandwidth. Surround sound distribution is not included in the scope of this profile."</i><br /><br /><b>Audio/Video Remote Control Profile (AVRCP)</b><br /><i>"AVRCP is designed to provide a standard interface to control TVs, hi-fi equipment, or other to allow a single remote control (or other device) to control all the A/V equipment that a user has access to. It may be used in concert with A2DP or VDP. AVRCP defines how to control characteristics of streaming media. This includes pausing, stopping and starting playback and volume control as well as other types of remote control operations. The AVRCP defines two roles, that of a controller and target device. The controller is typically considered the remote control device while the target device is the one whose characteristics are being altered. In a "walkman" type media player scenario, the control device may be a headset that allows tracks to be skipped and the target device would be the actual medial player. This protocol specifies the scope of the AV/C Digital Interface Command Set (AV/C command set, defined by the 1394 trade association) to be applied, realizing simple implementation and easy operability. This protocol adopts the AV/C device model and command format for control messages and those messages are transported by the Audio/Video Control Transport Protocol (AVCTP). In AVRCP, the controller translates the detected user action to the A/V control signal, and then transmits it to a remote Bluetooth enabled device. The functions available for a conventional infrared remote controller can be realized in this protocol. The remote control described in this protocol is designed specifically for A/V control only."</i><br /><br /><b>Hands-Free Profile (HFP)</b><br /><i>"HFP describes how a gateway device can be used to place and receive calls for a hand-free device. A typical configuration is an automobile using a mobile phone for a gateway device. In the car, the stereo is used for the phone audio and a microphone is installed in the car for sending outgoing audio. HFP is also used for a personal computer to act as a speaker phone for a mobile phone in a home or office environment. HFP uses SCO to carry a mono, PCM audio channel."</i><br /><br /><b>Headset Profile (HSP)</b><br /><i>"The HSP describes how a Bluetooth enabled headset should communicate with a computer or other Bluetooth enabled device such as a mobile phone. When connected and configured, the headset can act as the remote device's audio input and output interface. The HSP relies on SCO for audio and a subset of AT commands from GSM 07.07 for minimal controls including the ability to ring, answer a call, hang up and adjust the volume."</i><br /><PAGEBREAK><br /><span><b>Contents and Specifications</b></span><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-01.jpg" /><br /><i>Figure 1: All that's in the box. I reviewed the BT450Rx-L and BT450Tx combo pack, so the AC power adapter is not present.</i><br /><br />The i-PHONO mini combo package contains:<li>The Bluetooth stereo headphones (BT450Rx);<br /><li>A USB power cable (BT450Rx-L - Light Pack) or an AC power adapter (BT450Rx - Standard Pack);<br /><li>A Y-splitter power cable;<br /><li>A carrying pouch;<br /><li>A user manual;<br /><li>A utility CD (containing electronic versions of the manual).<br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-02.jpg" /><br /><i>Figure 2: The left earpiece, folded out. Note the charging socket and the hinged rubber cap.</i><br /><br />Rather than a hard plastic band, the iPHONO-mini has a 50cm wire connecting the two earpieces together. The inner surfaces of the earpiece are covered with soft foam. The plastic foldable ear clips are lined with soft rubber to provide a comfortable fit.<br /><br />Both earpieces, while appearing the same, do have some slight structural differences. The left earpiece has a charging socket that is covered by a hinged protective rubber cap.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-03.jpg" /><br /><i>Figure 3: The right earpiece, with the microphone, indicator light, and volume/playback rocker switch in view.</i><br /><br />The right earpiece has a power/call button at the top, a volume/playback rocker switch at the bottom, and a microphone at the front. An indicator light is present on the outer surface.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-04.jpg" /><br /><i>Figure 4: The right earpiece, with the power/call button in view.</i><br /><br />Here is a rundown of the headphones' specifications:<li>Dimensions: 44 x 37 x 20 mm (1.73 x 1.46 x 0.79 in.)<br /><li>Weight: 44 g (1.55 oz.) (Battery Included)<br /><li>Colours: Black / Charcoal / White<br /><li>Frequency Response: 20 Hz - 20 KHz<br /><li>Sample Rate: 48 KHz, 16 Bit<br /><li>Bluetooth Specification: Bluetooth v1.2 compliant<br /><li>Bluetooth Profiles Supported: A2DP (Advanced Audio Distribution Profile), AVRCP (Audio Video Remote Control Profile), HSP (Headset Profile), HFP (Hands-free Profile)<br /><li>Power Consumption: 222 mW<br /><li>Power Input: 5 V / 300 mA / 2.5 W<br /><li>Built-in Battery: 3.7 V / 300 mAh / Lithium / Rechargeable<br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-05.jpg" /><br /><i>Figure 5: The stereo transmitter and its universal audio adapter.</i><br /><PAGEBREAK><br />If you wish to use the i-PHONO mini headphones with a media device lacking Bluetooth, then the accompanying i-PHONO mini stereo transmitter works wonders. The transmitter, by default, fits into the connector of select models of the iPod range. The audio/remote plug on the transmitter is adjustable, since different iPods have different connector layouts. If, however, you wish to use the transmitter with a media device other than an iPod, you can connect the universal 3.5mm audio adapter to the transmitter, and then connect the transmitter to any device. The transmitter enables both A2DP and AVRCP support on the iPod, but when used with the adapter, only A2DP is supported.<br /><br />Here is a rundown of the transmitter's specifications:<li>Dimensions: 55 x 36.5 x 16 mm (2.17 x 1.44 x 0.63 in.)<br /><li>Weight: 36 g (0.92 oz.) (Battery Included)<br /><li>Stereo Plug: 3.5 mm (1/8 in.)<br /><li>Frequency Response: 20 Hz - 20 KHz<br /><li>Sample Rate: 48 KHz, 16 Bit<br /><li>Bluetooth Specification: Bluetooth v1.2 compliant<br /><li>Bluetooth Profiles Supported: A2DP (Advanced Audio Distribution Profile), AVRCP (Audio Video Remote Control Profile)<br /><li>Power Consumption: 190 mW<br /><li>Power Input: 5 V / 200 mA<br /><li>Built-in Battery: 3.7 V / 300 mAh / Li-Polymer / Rechargeable<br /><span><b>We'll Need Some Juice First!</b></span><br />The headphones and transmitter are powered by rechargeable lithium batteries. They aren't charged immediately out-of-the-box, so you will need to set aside a couple of hours of charging time in order to use the accessories. Because my BT450Rx-L and BT450Tx combo pack lacked an AC power adapter, I had to use the supplied USB cables for charging. They're great for travelling, but they have a downside in that they do not allow for simultaneous charging off a <i>single</i> cable (via the Y-splitter power cable) as most computers do not supply enough power to the USB ports.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-06.jpg" /><br /><i>Figure 6: Charging the headphones and transmitter with the supplied USB cables.</i><br /><br />Both first-time charging and subsequent charging cycles take approximately two hours. The indicator light on the transmitter indicates the progress of the charging cycle. It's red while charging, and blue when fully charged. The aforementioned applies to the headphones as well. It differs in two areas though - first, the charging indicator light is on the Y-splitter cable itself and not on the headphones; second, it uses red and green as its indicator colours.<br /><br /><span><b>Pairing and Establishing Connections</b></span><br />In this section of the review, I focus on connecting the headphones to two Bluetooth-enabled devices, the Dell Axim X50v and E-TEN M600, as well as a standard CD player via the Bluetooth stereo transmitter.<br /><br />A lot of today's Windows Mobile 5.0-based devices now use the Microsoft Bluetooth stack, as opposed to the Broadcom Bluetooth stack that was commonly employed in earlier versions of Windows Mobile. Prior to this review, my Axim X50v was running Windows Mobile 5.0 and it had not yet been updated with the Adaptation Kit Update 2.0 (AKU), which adds A2DP support to the Microsoft stack. As a result, I had to downgrade my device to Windows Mobile 2003 Second Edition in order to sample stereo audio through the Broadcom stack.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-07.jpg" /><br /><i>Figure 7: The Broadcom Bluetooth Manager searching for a device. And no, I'm not Bluetooth-enabled. My M600 (bearing the same name as me) is. ;)</i><br /><br />But, even in the current version of the Broadcom stack for the Axim X50 series, A2DP support is not present. However, HP's <a href="http://h18007.www1.hp.com/support/files/HandheldiPAQ/us/download/22475.html">iPAQ Bluetooth Stereo Headphones driver</a>, while not officially supporting the Axim, does actually work on it. When installed, it adds a new entry to the Bluetooth Manager titled "High Quality Audio Setup". This is markedly different to the other entry titled "Hands-free/Headset Setup" which only offers mono audio through HSP/HFP.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-08.jpg" /><br /><i>Figure 8: The Broadcom Bluetooth Manager requesting a passkey.</i><br /><PAGEBREAK><br />In order to connect the i-PHONO mini and the Axim X50v, you'll need to pair them first. To activate pairing mode on the headphones, you need to hold the power/call button and the volume/playback rocker switch simultaneously for two seconds. The indicator light will flash red and blue alternately. Next, turn on Bluetooth on the X50v, then launch the "Bluetooth Manager". Select "Tools" > "Paired Devices", then tap the "Add" button, followed by the "Search" icon. After a few seconds, the X50v will display something similar to Figure 7. Tap the "i-PHONO mini" entry and you'll be taken to a screen as shown in Figure 8.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-09.jpg" /><br /><i>Figure 9: The modified Broadcom Bluetooth Manager allows you to establish a high-quality audio connection to the i-PHONO mini. Some HP iPAQs should have this option, by default.</i><br /><br />Enter the standard <b>0000</b> number sequence as the passkey, tap "OK", and the devices will be paired. The next step involves the establishment of a high-quality audio connection (using A2DP). First, tap "New", then select the "High Quality Audio Setup" entry (Figure 9), and tap "Next". Select the paired i-PHONO mini, and create a shortcut for the connection. Tap-and-hold on the newly-created shortcut (Figure 10) and establish the connection if it hasn't been established already.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-10.jpg" /><br /><i>Figure 10: The Broadcom Bluetooth Manager should now show a new shortcut for a stereo connection to the i-PHONO mini.</i><br /><br />You can now use the headphones to play and control audio in a compatible media player such as Windows Media Player Mobile. Rolling the volume/playback rocker switch up and down will increase and decrease the volume respectively. Rolling it up and down and holding it for two seconds will switch between tracks. Lastly, pressing the rocker switch will play/pause/stop the track.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-11.jpg" /><br /><i>Figure 11: A2DP support aside, AVRCP can also be used to control the playback of media in Windows Media Player Mobile.</i><br /><br />The i-PHONO mini can also be made to work with select Windows Mobile 5.0 devices such as the E-TEN M600, which interestingly, supports A2DP and AVRCP but has not yet been updated with AKU 2.0. The setup procedure is much the same, though the M600 seems to treat the headphones as a standard HSP/HFP-enabled headset even though it uses the A2DP profile.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-12.gif" /><br /><i>Figure 12: Connecting the i-PHONO mini to the M600. Note the stereo headset icon shown in the Connectivity pop-up bubble.</i><br /><PAGEBREAK><br />As mentioned earlier, the BT450Tx transmitter offers all sorts of media devices the freedom of wireless - even those that aren't Bluetooth-enabled. Pairing the transmitter and headphones is simple and requires no real user input. First, pairing mode is enabled on the headphones. Next, pairing mode is enabled on the transmitter by holding down the universal button for a few seconds until the adjacent status indicator flashes red and blue. For a brief moment, the transmitter searches for the headphones and automatically adds them as a paired device. You need not enter a passkey. This is essentially a one-time process. The transmitter stores the paired device information in memory, so any future connection between it and the headphones is automatic.<br /><br />Once the transmitter is connected to a media device, stereo audio is wirelessly broadcast to the headphones. When connected, the indicator lights on both accessories flash blue.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-13.jpg" /><br /><i>Figure 13: Using the i-PHONO mini with the Sony D-EJ885 CD Walkman.</i><br /><br />Figures 13 and 14 show the transmitter connected to a Sony CD Walkman (with the universal audio adapter) and an iPod mini (without the universal audio adapter). The transmitter also includes a special remote connector that works with select models of the iPod range. So, aside from A2DP, AVRCP is supported, effectively allowing you to use the headphones to remotely control media on the iPod.<br /><br /><img src="http://www.pocketpcthoughts.com/images/web/2003/wey-bluetakeiphonomini-14.jpg" /><br /><i>Figure 14: Making that iPod wireless!</i><br /><br />You can also use the i-PHONO mini as a hands-free headset for use with a mobile phone. If you use a Pocket PC Phone Edition, then that may happen to be your universal device for communications and media. The process of pairing and connecting it to a phone is much the same. Where the headphones are being used on a device which supports both HFP/HSP and A2DP, it's able to switch profiles automatically when answering/making a call.<br /><br />While the i-PHONO mini is certainly usable as a hands-free headset (with the power/call supporting the answering and ending of calls), it does have a slight background hiss, and the microphone isn't of the noise-cancelling variety. If you already have a dedicated hands-free headset, then you may want to continue using it for communications, unless your lifestyle demands the convenience of an all-in-one headset such as the i-PHONO mini.<br /><PAGEBREAK><br /><span><b>Comfort and Performance</b></span><br />Battery included, the i-PHONO mini headphones weigh just 44g. Yes, these things are light! Nothing annoys me more than earclip headphones that weigh down the ear. Thankfully, the i-PHONO mini doesn't fall into that category. They are very comfortable to wear and the inner surface isn't overly padded, so you won't have to worry about hot and sweaty ears.<br /><br />I've put both the headphones and the transmitter through a number of charge-discharge cycles. On a full charge, both last around 6-7 hours each. I think that's adequate for a day's worth of music. In fact, it's late afternoon now, and I've been using the headphones all day - while posting in the forums and writing this review.<br /><br />The audio quality of the i-PHONO mini is decent. Its frequency response is 20-20000Hz, which is a standard range for a lot of today's corded headphones. If you're an audio junkie (DJ, musician, etc.), the i-PHONO mini won't outdo your best set of headphones, but for everyday listening, they'll work great and will easily beat any cheap headphones that can be found in a standard electronics store.<br /><br />Finally, I found the operating range of the headphones and transmitter to fall just short of the specified ten metres. In an open environment, I managed to get about six to seven metres instead.<br /><br /><span><b>Conclusions</b></span><br />The i-PHONO mini headphone and transmitter package isn't cheap, but if you demand the convenience of Bluetooth and an all-in-one device, then the i-PHONO mini is well worth the money spent. It's well-built and the audio quality over A2DP is excellent. It's a shame that a lot of today's Pocket PCs, while equipped with Bluetooth, do not yet support A2DP since AKU 2.0 has not yet been widely implemented on a lot of the devices running the Microsoft stack. Having said that, I do see the use of Bluetooth headphones booming this year, and if you want in on the trend, then the i-PHONO mini is a great pick.<br /><br /><i>Darius Wey loves technology! When he's not working at this web site, he's busy working for his medical degree (MBBS) and dabbling in audio and video editing, web and graphic design, photography and the odd bit of mobile development. He lives in Perth, Western Australia.</i>